# Special Flight Rules in the Vicinity of Grand Canyon National Park

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URL: https://www.frixlaw.com/law-library/documents/fr%3A96-33146

## Record

- **Collection:** Federal Register
- **Document type:** Rule
- **Published:** December 31, 1996
- **Citation:** 61 FR 69302

## Text

SUMMARY: This final rule is one part of an overall strategy to further
reduce the impact of aircraft noise on the park environment and to
assist the National Park Service in achieving its statutory mandate,
imposed by Public Law 100-91, to provide for the substantial
restoration of natural quiet and experience in Grand Canyon National
Park. This action is issued concurrently with: a Notice of Proposed
Rulemaking regarding Noise Limitations for Aircraft Operations in the
Vicinity of Grand Canyon National Park; a Notice of Availability of
Proposed Commercial Air Tour Routes for Grand Canyon National Park and
Request for Comments; and the Environmental Assessment issued with this
final rule. This action amends part 93 of the Federal Aviation
Regulations by adding a new subpart to codify the provisions of Special
Federal Aviation Regulation No. 50-2, Special Flight Rules in the
Vicinity of Grand Canyon National Park; modifies the dimensions of the
Grand Canyon National Park Special Flight Rules Area; establishes new
and modifies existing flight-free zones; establishes new and modifies
existing flight corridors; and establishes reporting requirements for
commercial sightseeing companies operating in the Special Flight Rules
Area. In addition, to provide further protection for park resources,
this final rule prohibits commercial sightseeing operations in the Zuni
and Dragon corridors during certain time periods, and limits the number
of aircraft that can be used for commercial sightseeing operations in
the Grand Canyon National Park Special Flight Rules Area.

EFFECTIVE DATE: May 1, 1997.

FOR FURTHER INFORMATION CONTACT: Mr. Neil Saunders, Airspace and Rules
Division, ATA-400, Office of Air Traffic Airspace Management, Federal
Aviation Administration, 800 Independence Avenue, SW., Washington, DC
20591; Telephone: (202) 267-8783. For the Environmental Assessment
contact Mr. William J. Marx, Manager, Environmental Programs Division,
ATA-300, Office of Air Traffic Airspace Management, Federal Aviation
Administration, 800 Independence Avenue, SW., Washington, DC 20591;
Telephone: (202) 267-3075.

SUPPLEMENTARY INFORMATION:

History

Beginning in the summer of 1986, the FAA initiated regulatory
action to address increasing air traffic over Grand Canyon National
Park (GCNP). On March 26, 1987, the FAA issued Special Federal Aviation
Regulation (SFAR) No. 50 (subsequently amended on June 15, 1987; 52 FR
22734) establishing flight regulations in the vicinity of the Grand
Canyon. The purpose of the SFAR was to reduce the risk of midair
collision, reduce the risk of terrain contact accidents below the rim
level, and reduce the impact of aircraft noise on the park environment.
In 1987, Congress enacted Public Law (Pub. L.) 100-91, commonly
known as the National Parks Overflights Act. Public Law 100-91 stated,
in part, that noise associated with aircraft overflights at GCNP was
causing ``a significant adverse effect on the natural quiet and
experience of the park and current aircraft operations at the Grand
Canyon National Park have raised serious concerns regarding public
safety, including concerns regarding the safety of park users.''
Section 3 of Public Law 100-91 required the Department of the
Interior (DOI) to submit to the FAA recommendations to protect
resources in the Grand Canyon from adverse impacts associated with
aircraft overflights. The law mandated that the recommendations: (1)
Provide for substantial restoration of the natural quiet and experience
of the park and protection of public health and safety from adverse
effects associated with aircraft overflight; (2) with limited
exceptions, prohibit the flight of aircraft below the rim of the
canyon; and (3) designate flight-free zones except for purposes of
administration and emergency operations.
In December 1987, the DOI transmitted its ``Grand Canyon Aircraft
Management Recommendation'' to the FAA, which included both rulemaking
and nonrulemaking actions. Public Law 100-91 required the FAA to
prepare and issue a final plan for the management of air traffic above
the Grand Canyon, implementing the recommendations of the DOI without
change unless the FAA determined that executing the recommendations
would adversely affect aviation safety. After the FAA determined that
some of the DOI recommendations would adversely affect aviation safety,
the recommendations were modified to resolve those concerns.
On May 27, 1988, the FAA issued SFAR No. 50-2 revising the
procedures for operation of aircraft in the airspace above the Grand
Canyon (53 FR 20264, June 2, 1988). SFAR No. 50-2 established a Special
Flight Rules Area (SFRA) from the surface to 14,499 feet above mean sea
level (MSL) in the area of the Grand Canyon. The SFAR prohibited flight
below a certain altitude in each of five sectors of this area, with
certain exceptions. The SFAR established four flight-free zones from
the surface to 14,499 feet MSL covering large areas of the park. The
SFAR provided for special routes for commercial sightseeing operators,
which are required to conduct operations under part 135, as authorized
by special operations specifications. Finally, the SFAR contained
certain terrain avoidance and communications requirements for flights
in the area.
A second major provision of section 3 of Public Law 100-91 required
the DOI to submit a report to Congress ``* * * discussing * * * whether
[SFAR No. 50-2] has succeeded in substantially restoring the natural
quiet in the park; and * * * such other matters, including possible
revisions in the plan, as may be of interest. The report was to include
comments by the FAA ``regarding the effect of the plan's implementation
on aircraft safety.'' Public Law 100-91 mandated a number of studies
related to the effect of overflights on parks.
On September 12, 1994, the DOI submitted its final report and
recommendations to Congress. This report, entitled, ``Report on Effects
of Aircraft Overflights on the National Park System'' (Report to
Congress), was published in July 1995. The Report to Congress
recommended numerous revisions to SFAR No. 50-2 in order to
substantially restore natural quiet in GCNP. Recommendation No. 10,
which is of particular interest to this rulemaking, states: ``Improve
SFAR 50-2 to Effect and Maintain the Substantial Restoration of Natural
Quiet at Grand Canyon National Park.'' This recommendation incorporated
the following general concepts: Simplification of the commercial
sightseeing route structure; expansion of flight-free zones;
accommodation of the forecast growth in the air tour industry; phased-
in use of quieter aircraft technology; temporal restrictions (``flight-
free'' time periods); use of the full range of methods and tools for

[[Page 69303]]

problem solving; and institution of changes in approaches to park
management, including the establishment of an acoustic monitoring
program by the National Park Service (NPS) in coordination with the
FAA.
On June 15, 1995, the FAA published a final rule that extended the
provisions of SFAR No. 50-2 to June 15, 1997 (60 FR 31608). This action
allowed the FAA sufficient time to review the NPS recommendations and
to initiate and complete appropriate rulemaking action.

Interagency Working Group

On December 22, 1993, Secretary of Transportation Federico Pena and
Secretary of the Interior Bruce Babbitt formed an interagency working
group (IWG) to explore ways to limit or reduce the impacts from
overflights on national parks, including GCNP. Secretary Babbitt and
Secretary Pena concurred that increased flight operations at GCNP and
other national parks have significantly diminished the national park
experience for some park visitors, and that measures can and should be
taken to preserve a quality park experience for visitors, while
providing access to the airspace over national parks. The FAA has been
working closely with the NPS to identify and deal with the impacts of
aviation on parks, and the two agencies will continue to identify and
pursue the most effective solutions.
The FAA's role in the IWG has been to promote, develop, and foster
aviation safety, and to provide for the safe and efficient use of
airspace, while recognizing the need to preserve, protect, and enhance
the environment by minimizing the adverse effects of aviation on the
environment. The NPS' role in the IWG has been to protect public land
resources in national parks, preserve environmental values of those
areas, including wilderness areas, and provide for public enjoyment of
those areas.
In March 1994, the two agencies jointly issued an advance notice of
proposed rulemaking (ANPRM) seeking public comment on policy
recommendations addressing the effects of aircraft overflights on
national parks, including GCNP (59 FR 12740; March 17, 1994). The
recommendations presented for comment included voluntary measures,
altitude restrictions, flight-free periods, flight-free zones,
allocation of noise equivalencies, and incentives to encourage use of
quiet aircraft technology. In response to the ANPRM, the FAA received
644 comments that specifically addressed GCNP. These comments were
summarized in the NPRM published on July 31, 1996 (61 FR 40120; Notice
96-11).

President's Memorandum

The President, on April 22, 1996, issued a Memorandum for the Heads
of Executive Departments and Agencies to address the significant
impacts on visitor experience in national parks. Specifically, the
President directed the Secretary of Transportation to issue proposed
regulations for GCNP that would place appropriate limits on sightseeing
aircraft to reduce the noise immediately and make further substantial
progress towards restoration of natural quiet, as defined by the
Secretary of the Interior, while maintaining aviation safety in
accordance with Public Law 100-91.

Notice of Proposed Rulemaking Draft Environmental Assessment

On July 31, 1996 the FAA published an NPRM (61 FR 40120; Notice 96-
11), to reduce the impact of aircraft noise on GCNP and to assist the
NPS in achieving its statutory mandate imposed by Public Law 100-91 to
provide for the substantial restoration of natural quiet and experience
in GCNP. Notice 96-11 proposed the following: Codification and
amendment to the SFAR 50-2, Special Flight Rules in the Vicinity of
GCNP; modification of the dimensions of the Grand Canyon National Park
Special Flight Rules Area; establishment of new flight-free zones and
flight corridors, as well as modification of existing flight-free zones
and flight corridors; establishment of flight-free periods (curfews)
and/or an interim moratorium on additional commercial sightseeing air
tours or tour operators (caps); and establishment of reporting
requirements for commercial sightseeing companies operating in the
SFRA. In addition to these areas, the FAA sought comment on a number of
questions and alternatives regarding curfews and caps, as well as on
the issue of quiet aircraft technology. The comment period for the
proposed rule, originally set for 60 days, was subsequently extended
for 45 days (61 FR 54716; October 21, 1996) as directed by the Congress
in the Federal Aviation Authorization Act of 1996.
On August 21, 1996, the notice of availability of the draft
Environmental Assessment (EA) was published in the Federal Register (61
FR 43196). Comments on the draft EA were to be received on or before
October 4, 1996. This date was subsequently extended, as directed by
Congress in the Federal Aviation Authorization Act of 1996, to November
18, 1996.
Comments received in response to this Notice of Availability of the
draft EA have been addressed in the final EA published concurrently
with this final rule.

Public Meetings

On September 16-20, 1996, in Scottsdale, AZ, and Las Vegas, NV, the
FAA held public meetings to obtain additional comment on the Notice 96-
11 and on the draft environmental assessment. Comments and the
transcripts of these meetings have been placed in the rulemaking
docket.
The following information summarizes what occurred at the public
meetings on the Grand Canyon NPRM and draft EA, held in Scottsdale,
Arizona, September 16 and 17, 1996, and Las Vegas, Nevada, September 19
and 20, 1996.
Senator Reid of Nevada, by proxy in Las Vegas, noted his opposition
to the proposed rule. He indicated that 44 percent of the Canyon was
already covered by flight-free zones, and that only 14 percent of park
airspace is available to the operators now. He also opined that (1) the
requirements of Public Law 100-91 (i.e., substantial restoration of
natural quiet) have been accomplished by the SFAR; and (2) the new rule
would have major adverse impacts on safety and economics. He foresaw
devastating financial impacts on the air tour industry and on local
communities. Congresswoman Vucanovich of Nevada, also by proxy in Las
Vegas, indicated that she was concerned about the effects of the
proposed rule on the air tour industry, noting that there were no
flight routes specified in Notice 96-11. She believed that flight-free
periods/curfews would raise both economic and safety issues. She also
believed that an Environmental Impact Statement (EIS), as opposed to an
EA, was required under the National Environmental Policy Act (NEPA)
based on the highly controversial nature of the NPRM.
The air tour operators talked about potential adverse economic
impacts of the NPRM, potential negative impacts on safety--such as
compressing more flights into the smaller areas as the result of
curfews and additional flight-free zones--and the importance of quiet
aircraft technology, and incentives to manufacture and use quieter
aircraft, noting specifically that quieter aircraft are far more
expensive to purchase and operate than are noisier aircraft. A number
of operators emphasized their belief that ``SFAR 50-2 works,'' both
from safety and environmental standpoints. Many of these same operators
questioned the NPS's

[[Page 69304]]

definitions of natural quiet and substantial restoration thereof, and
challenged the science involved, including noise modeling conducted by
both FAA and NPS, in measuring the noise impacts of commercial air tour
overflights and in assessing the degree to which natural quiet has been
restored under SFAR 50-2. Several operators and representatives of
aircraft manufacturers offered concrete suggestions as to the kinds of
incentives that might prove useful.
As for other aviation interests, general aviation groups expressed
concerns about their constituents' ability to transit the park safely
and conveniently.
Representatives of environmental groups and individual
environmentalists pointed out that the addition of two flight-free
zones is misleading, in that aircraft noise can travel from 13-16 miles
laterally, so the flight-free zones are not free of noise. A number of
environmentalists indicated that the NPS's definition of substantial
restoration of natural quiet is too liberal and allows too much
aircraft noise. They also pointed out that, in contrast to the lack of
control on air tour overflight volume, there are tight controls on all
commercial activities on the ground in parks. Environmentalists spoke
favorably about the promise of quieter aircraft technology and
supported the development of incentives to manufacture and use quieter
aircraft.
Representatives of Native American tribes living in and around the
Grand Canyon expressed major disappointment with what they viewed as
the failure by the FAA and NPS to consult with them adequately on the
NPRM and the draft EA. They emphasized that the net effect of the
revised rule would be to relocate noise impacts from the park to tribal
lands, with concomitant adverse effects on their natural and cultural
resources and on the health and safety of tribe members and visitors to
tribal lands. They believed that the situation called for an EIS, not
an EA.
While the FAA held separate meetings in both Scottsdale, AZ, and
Las Vegas, NV, on the NPRM and the EA, a number of commenters at the
NPRM meetings addressed the EA as well, and vice versa. The majority of
comments from all ``sides'' of the issue were negative with regard to
the EA itself, which many found inadequate for a variety of reasons,
including the fact that the range of alternatives was limited to either
no action or the proposed alternative, and an overall lack of
specificity. Several commenters pointed to inconsistencies between FAA
and NPS noise modeling methodologies, which led the agencies to two
different conclusions as to the potential effectiveness of the revised
rule. Air tour operators pointed out that the potential adverse impacts
of the NPRM on their operations, including safety concerns, were not
justified in view of FAA's findings that the proposed alternative would
not provide any significant improvement in natural quiet, while
environmentalists argued that the EA failed to include any alternative
which would substantially restore natural quiet to the park. More than
a few commenters felt that NEPA compliance in this case required an
EIS, not an EA.
One of the few areas of common ground to emerge from these meetings
was widespread support for further use of quieter aircraft technology
and for the development and implementation of incentives to manufacture
and use quieter aircraft.

Congressional Hearings

From October 10 to 11, 1996, Congressional hearings were held by
the Aviation Subcommittee of the Senate Committee on Commerce, Science,
and Transportation in Las Vegas, Nevada, and Tempe, Arizona. The
hearings were held to gather testimony from various entities involved
in or affected by the FAA's proposed Special Flight Rules in the
Vicinity of Grand Canyon National Park. Senator McCain of Arizona
chaired and made opening statements at both field hearings indicating
that they were there to examine the impacts of the proposed rule and
the draft environmental assessment. He expressed his disappointment in
the lack of mention of quiet aircraft technology in Notice 96-11,
indicating that he hoped FAA would provide appropriate incentives in
the final rule.
The Nevada Congressional delegation (Senator Bryan and Congressman
Ensign in person, Senator Reid and Congresswoman Vucanovich by proxy)
indicated, at the Las Vegas hearing, their opposition to Notice 96-11
as written, noting safety concerns as well as ones related to
economics, NEPA compliance, and the lack of quiet aircraft technology
incentives.
The issues raised by Senator McCain and the Arizona delegation were
also addressed by others testifying at the field hearings. There were
points and counterpoints raised as to the effectiveness of SFAR 50-2 in
substantially restoring natural quiet in the Grand Canyon, as mandated
by Public Law 100-91; NPS's definition of substantial restoration (50
percent or more of the park quiet at least 75-100 percent of the day);
methodology involved in measuring and modeling noise impacts; potential
impacts of the new rule on safety in the SFRA; effects of the new rule
on general aviation; potential adverse impacts of the rule on the
economy of Las Vegas and Nevada; adequacy of the consultation process
with Native American tribes; and controls on other users of the park
vis-a-vis air tour overflights.
Many of the air tour operators, some of whom had also voiced
concerns about the safety implications of Notice 96-11, predicted dire
economic consequences for the industry if the NPRM, which included
possible caps on operations, curfews, and two additional flight-free
zones, went into effect. In response to the operators' economic
concerns, Senator McCain reminded them that they had unanimously
opposed his bill, which became Public Law 100-91, in 1987, claiming
that it would put the entire industry out of business. Instead, he
noted, the number of air tour overflights of Grand Canyon had increased
from approximately 40,000 per annum in 1987 to the 95,000 reported by
the Arizona Republic newspaper during the 12-month period which ended
September 30, 1996.
Aside from a commitment to air safety, perhaps the only issue on
which all of the interests represented at the field hearings could
agree was the need for quiet aircraft technology incentives for both
manufacturers and air tour operators. From Senator McCain and members
of the Nevada Congressional delegation to the Native American Indian
tribal leaders and from environmental groups to air tour operators and
aircraft manufacturers, as well as aviation and tourism industry
representatives, quieter aircraft technology incentives were viewed as
integral to efforts to substantially restore natural quiet to the Grand
Canyon while maintaining a viable air tour industry. Among specific
suggestions made were providing more attractive routes to quieter
aircraft, setting aside a portion of air tour overflight fees to
provide loans to air tour operators to invest in further quiet aircraft
technology, and lowering fees for those operators using quieter
aircraft.
The FAA has considered the statements made at the hearings in
developing this final rule and the Notice of Proposed Rulemaking
regarding Noise Limitations for Aircraft Operations in the Vicinity of
the Grand Canyon National Park found in this part of today's Federal
Register.

[[Page 69305]]

Consultation with Affected Native American Tribes

The Navajo, Hualapai, and Havasupai Native American reservations
border GCNP, and several other tribes have cultural ties to the Grand
Canyon. The DOT and DOI have satisfied their obligation to consult with
these tribes, on a government-to-government basis concerning the
possible effects of this rule, as required under applicable statutes,
regulations, and Executive Orders. Although they did not elect to do
so, the tribes were invited to participate as cooperating agencies in
the environmental review process. Their major concerns were recognition
of their sovereignty over the airspace, air access, potential noise
increases over tribal lands and religious/historic/cultural sites, and
the lack of early coordination during the development of the proposed
rule. Both DOT and DOI have addressed tribal concerns, including the
effects of the rule on economic opportunities of the tribes, in
preparing this final rule. The consultation process, and the mitigation
commitments made to address tribal concerns, are described in detail in
the final EA, a copy of which has been included in the docket for the
final rule.
The consultation process, which began with the development of
Notice 96-11, for reduction of aircraft noise, will continue. This will
include a dialogue in which potentially affected tribes will have the
opportunity to identify, on a confidential basis, any religious,
cultural, or historic area that may be potentially affected by
significant noise increases. The FAA has committed to mitigate any such
impacts during the development of air tour routes for GCNP.

Public Input

As previously mentioned, on July 31, 1996, the FAA published Notice
96-11 in the Federal Register proposing several actions to reduce the
impact of aircraft noise on GCNP and assist the NPS in its efforts to
substantially restore natural quiet and experience in the park.
Interested persons were invited to participate in this rulemaking
action by submitting written data, views, or arguments. In response to
this notice, the FAA received approximately 14,000 comments. Almost 95
percent of these comments were form letters, or virtual form letters,
stating a position either favoring restrictions on air tour overflights
or opposing them, with no substantive discussion. While all comments
received were considered before issuing this final rule, the specific
comments addressed in this preamble are those that contained
substantive information.
The following is an analysis of the pertinent general comments
received in response to Notice 96-11. Later in the document the FAA has
included a section-by-section analysis of the rule, including a
discussion of the relevant comments related to each of these sections,
and rationale of the final rule.

Discussion of Pertinent General Comments

Comments were received from industry associations (e.g., Grand
Canyon Air Tour Council, United States Air Tour Association, Aircraft
Owners and Pilots Association, Helicopter Association International);
environmental groups (e.g., Sierra Club, National Parks and
Conservation Association); air tour operators; aircraft manufacturers;
government officials; and Native American tribes (e.g., Havasupai
Tribe, Hualapai Tribe).
Approximately one-third of the comments support overflight
restrictions to reduce aircraft noise over GCNP. Many of these
commenters say that, even with the current SFAR, the noise problem has
worsened as the air tour industry has grown. These commenters want to
see the proposal strengthened to preserve the natural quiet of the park
and recommend permanent caps on the number of air tour flights (based
on the number of flights in 1987 when Public Law 100-91 was passed);
expansion of the flight-free zones; stricter curfews; and incentives
for the use of quiet aircraft (combined with caps and curfews).
Approximately two-thirds of the comments oppose further overflight
restrictions. These commenters argue that SFAR 50-2 has been successful
in reducing noise (as shown by visitor surveys); air tour operations
allow everyone access to the park and have less environmental impact on
the park than do ground visitors; the proposed flight corridors and
flight-free zones could create safety problems by causing denser
traffic patterns; and the air tour industry would face severe economic
consequences.

Statutory Authorities

A few commenters state that Notice 96-11 is basically allowing the
NPS to regulate the airspace over the national parks, thereby diluting
the authority of the FAA. Others state that the FAA has no authority to
regulate noise over the national parks, that the FA Act (now codified
in 49 U.S.C.) authorizes the FAA to regulate safety, and to regulate
noise only as it concerns aircraft certification.
Several commenters focus on the authority provided in Public Law
100-91. Some of these commenters do not believe that Public Law 100-91
gives the FAA the authority to do more than it has already done in
issuing SFAR 50-2. One commenter states that since Public Law 100-91
requires NPS to submit its report on the effectiveness of the airspace
management plan to Congress, only Congress was intended to review the
NPS recommendations and provide specific guidance on what further
agency action, if any, would be appropriate.
A presenter at the Congressional hearing, as well as an individual
from the Navajo Area Office of the BIA commenting to the docket, adds
that Public Law 102-581 (The Airport and Airway Safety, Capacity, Noise
Improvement Transportation Act of 1992) (also related to aircraft noise
at the Grand Canyon), called for a report to Congress outlining the
FAA's plan to manage increased air traffic over GCNP. As in Public Law
100-91, this report would be used only by Congress for any further
action. Another commenter states that the FAA and NPS have done only
half of the task mandated under Public Law 100-91 since they have not
yet proposed the air tour routes that will be followed. An air tour
operator comments that the proposal does not comply with Public Law
100-91 because the statute requires an overflight system that will
substantially protect the ground visitor from aircraft noise, while the
proposal is based on a standard called percent time audible.
One commenter believes that the FAA has violated the Administrative
Procedure Act by not providing a reasonable opportunity for public
comment on the meanings of the terms ``natural quiet'' and
``substantial restoration of natural quiet.''
Two commenters state that the proposal violates the Americans with
Disabilities Act and provisions of the FA Act that guarantee air access
to elderly and disabled persons. Counter to these commenters, another
commenter states that most handicapped visitors see the park from the
rim overlooks and paved rim trails and that such visitors should not be
an excuse for the park's inability to achieve its Congressional
mandated goal of substantial restoration of natural quiet.
FAA Response: The FAA has broad authority and responsibility to
regulate the operation of aircraft and the use of the navigable
airspace and to establish safety standards for and regulate the
certification of airmen, aircraft, and air carriers. 49 U.S.C. 40101,
et seq. Subtitle VII of Title 49 U.S.C. provides guidance

[[Page 69306]]

to the Administrator in carrying out this responsibility. Moreover, the
FAA's authority is not limited to regulation for aviation safety and
efficiency.
The FAA has authority to manage the navigable airspace to protect
persons and property on the ground. The Administrator is authorized to
``prescribe air traffic regulations on the flight of aircraft
(including regulations on safe altitudes) for-- * * * (B) protecting
individuals and property on the ground.'' 49 U.S.C. 40103(b)(2). In
addition, under 49 U.S.C. 44715(a) the Administrator of the FAA, in
consultation with the Environmental Protection Agency, is directed to
issue such regulations as the FAA may find necessary to control and
abate aircraft noise and sonic boom to ``relieve and protect the public
health and welfare.''
The FAA construes these provisions, taken together, to authorize
the adoption of this regulation. It is the general policy of the
Federal Government that the FAA, like other agencies, will exercise its
authority in a manner that will enhance the environment. Section 101 of
the National Environmental Policy Act of 1969, as amended 42 U.S.C.
4321 and Executive Order 11514, as amended by Executive Order 11991.
The unambiguous intent of Public Law 100-91 with respect to the
Grand Canyon was for the FAA to work cooperatively with the NPS to
devise a plan that would safely provide for a substantial restoration
of natural quiet while maintaining a viable air tour industry. For this
reason Sections 3(b)(3) (A) and (B) provided for an evaluation of the
initial plan and any necessary revisions based upon that evaluation.
Because the report recommended regulatory action rather than
legislative action, the FAA was not constrained to wait for
Congressional response. For GCNP, the law specifically addressed the
substantial restoration of natural quiet, not the protection of ground
visitors.
Public Law 102-581 required the FAA to submit to Congress a report
on increased air traffic over GCNP. This report, like the report
required to be submitted by Public Law 100-91, did not limit the
ability of the FAA to use its general regulatory authority to take
appropriate actions in implementing provisions of either report.
Indeed, Public Law 102-581 specifically requires a plan of action to
``manage increased air traffic over Grand Canyon National Park to
ensure aviation safety and to meet the requirements established by such
Section 3 of the Act of August 18, 1987, including any measures to
encourage or require the use of quiet aircraft technology by commercial
air tour operators.'' Public Law 102-581, Section 134(b)(4).
Both the FAA and NPS recognize that additional work will be
necessary in delineation of air tour routes to be followed as well as
other actions. In consultation with the NPS, FAA has proposed air tour
routes in a separate notice issued concurrently with this final rule.
Additionally, in a separate Notice of Proposed Rule Making issued
today, further actions to facilitate the substantial restoration of
natural quiet to the Grand Canyon have been proposed. Both this final
rule and the NPRM acknowledge the need for the development of a Noise
Management Plan to further mitigate impacts from commercial
overflights. These actions are also taken in full recognition that the
restoration of natural quiet to the Canyon will require these
additional steps to meet the definitions established for natural quiet.
The rationale for the establishment of the percent time audible is
included in the NPS report to Congress. While this methodology may
differ from some measurements, it assures protection of the ground
visitor from aircraft noise. Furthermore, the threshold of audibility
used in the NPS model is louder than the level which would be detected
by an attentive listener, guaranteeing that virtually all visitors
would notice the noise while engaged in normal visitor activities.
The terms ``natural quiet'' and ``substantial restoration of
natural quiet'' are taken from language in Public Law 100-91. These
terms were defined in the Report to Congress issued by the NPS under
the direction of that Act. That report has been available to the public
and its role in the development of this regulatory proposal has been
clearly defined in previous notices, including the ANPRM on this rule.
The concepts of ``natural quiet'' and ``substantial restoration of
natural quiet'' have been the subject of academic research, agency
disclosure and adversarial dialogue for a number of years and are used
as recognized technical benchmarks in the analysis of the effects of
this rule. As such, the terms do not need additional comment under the
Administrative Procedure Act.
In addition, the Grand Canyon Enlargement Act specifically provides
that the Department of Interior shall submit to the FAA and EPA
pursuant to 49 U.S.C. 44715 any recommendations for rules or
regulations or other actions he believes appropriate to protect the
public health, welfare, and safety or natural environment within the
park. After reviewing the submission of the Secretary, the FAA is to
take appropriate action.
This action does not violate provisions of the Americans with
Disabilities Act or any other guarantees of air access to elderly or
disabled persons. The disabled and the elderly will still have a
variety of opportunities to view the Grand Canyon by air. In addition,
opportunities for ground visits to GCNP will also be as available as
they are at present. Provisions for ground access include issuance of
special permits to the elderly and handicapped for access to areas
closed to automobiles at certain times of the year. Visitor facilities
within the park, including overnight accommodations, restaurants and
developments are accessible to the handicapped and the elderly.

Impact on Tribal Lands

An individual from a local office of the Bureau of Indian Affairs
(BIA) and representatives of Native American tribes affected by this
rulemaking state that the FAA and NPS have violated certain treaties,
statutes, and Executive Orders by not consulting with the affected
tribes during the development of Notice 96-11 and by not analyzing the
impact the proposed rule would have on these tribes and their lands.
FAA Response: The FAA disagrees that treaties, statutes, and
executive orders have been violated by not consulting with affected
Native American tribes. Public involvement is an important part of the
rulemaking process. Public hearing activities have included public
meetings with interested parties and consultation with Native
Americans. The FAA has not yet received concurrence from the Arizona
Historic Preservation Officer and the Tribal Historic Preservation
Office for the Hualapai Tribe in a determination of no adverse effect
pursuant to Section 106. The FAA will continue to consult and work with
Native American Nations and Tribes during development of the air tour
routes to address any requested measures to minimize noise increases
over specifically identified traditional cultural sites as part of the
Section 106 process. This includes areas potentially affected by
traffic and air tour routes outside the Flight Free Zones.
An initial determination of no adverse effect by the FAA was based
upon an analysis of cultural resources in the vicinity of the GCNP as
identified by the NPS and knowledge shared by Native American tribes
with comtemporary and ancestral involvement with the Grand Canyon.
Native Americans tribes may have been reluctant to identify the
locations of other specific sites of concern due to a desire to limit
public access and preserve their sacred character and integrity. The
FAA

[[Page 69307]]

commits to preserve the confidentiality of the locations of any
specifically identified traditional cultural sites that the Native
Americans elect to disclose to the FAA during consultation to establish
the air tour routes. The FAA further commits to complete Section 106
consultation before it finalizes and permanently implements the air
tour routes and to adopt all measures necessary to support a
determination of no adverse effect. The FAA will also adopt all
measures necessary to assure that the routes developed to implement the
proposed final rule do not substantially interfere with the use of
sacred religious sites of the Native American tribes in the vicinity of
the GCNP.
As discussed in detail in Chapter 4.2 of the Environmental
Assessment (EA), the FAA will continue to consult and work with Native
American Tribes pursuant to Section 106, during development of the air
tour routes to address any requested measures to minimize noise
increases over traditional cultural properties as part of the Section
106 process. This includes areas potentially affected by traffic and
air tour routes outside the Flight Free Zones, like the 10-12 miles
radius around the confluence of the Little Colorado and Colorado Rivers
that was identified by the Hopi Tribe.
The FAA will protect any confidentiality requested to limit public
access and preserve the character and integrity of sacred sites. The
FAA will complete Section 106 consultation before it finalizes and
permanently implements the air tour routes and will adopt all measures
necessary to support a determination of no adverse effect. The FAA will
also adopt all measures necessary to assure that the routes developed
to implement the proposed final rule do not substantially interfere
with the religious practices of the Native American tribes.
On June 28, 1995, the FAA and NPS jointly published a notice
announcing a public meeting to provide the interested parties with an
opportunity to comment on improving SFAR 50-2 (60 FR 33452). The
meeting, held on August 30, 1995, yielded 62 speakers representing air
tour operators, environmentalists, government, tourist boards,
corporations, Native American tribes, and other individuals. An
additional 349 public comments were subsequently received during the
comment period that ended on September 8, 1995.
The FAA sponsored public meetings, in Scottsdale, Arizona, on
September 16 and Las Vegas, Nevada, on September 19, 1996, to receive
comments on the NPRM. These meetings were announced in the Federal
Register on August 30 (61 FR 45921) and in newspapers in Phoenix,
Flagstaff, and Kingman, Arizona, and Las Vegas, Nevada, on several
dates in early September.
On August 27 and 28, 1996, the FAA hosted a meeting in Flagstaff,
Arizona, at which tribal representatives were given the opportunity to
express their views on the rule. FAA invited two representatives each
from the Hualapai, Havasupai, Hopi, San Juan Southern Paiute, Paiute of
Utah, and Kaibab Piaute Tribes, the Pueblo of Zuni, and the Navajo
Nation. During the meetings, the Native American representatives were
given a detailed briefing by the FAA on changes proposed in the NPRM.
Following the briefing, there was a question-and-answer session where
FAA and NPS representatives fielded questions on the revised rule.
Minutes of the meeting were provided to each tribe that was invited.
Subsequently, from October 14 to 21, 1996, representatives of the
FAA met on-site in Arizona, New Mexico, and Utah with representatives
of each tribe to further assess the concerns of the Native Americans.
Each tribe was offered a briefing on the proposed rule and given the
opportunity to ask questions of the FAA representatives.
Other opportunities have been provided for the tribes to make their
views known to the DOT. The Hualapai Tribe submitted comments to the
Advance Notice for Proposed Rulemaking (ANPRM) jointly issued by the
DOT and DOI. One member of the Hualapai Tribe spoke at the Flagstaff
public meeting, and the Hualapai Tribe submitted written comments in
response to the public meeting. The Hualapai Tribe commented on the
need for a socio-economic analysis of the proposed flight restrictions
on the Hualapai Nation. The Chairman of the Hualapai Tribe spoke at the
Las Vegas public meeting. Written comments have been received into the
docket from the Hualapai, Hopi, and Havasupai Tribes.
Additionally, informal discussions covering aircraft overflight
matters, among other issues, have taken place between NPS personnel and
tribal leaders locally. The DOT and the DOI have received
correspondence identifying interests of the Hualapai Tribe, and the DOT
and the FAA met with Hualapai leaders on several occasions and heard
first hand many of their specific concerns.

Special Federal Aviation Regulation No. 50-2

Several commenters believe that SFAR 50-2 is working and further
regulation is not necessary. According to these commenters complaints
about noise have been practically eliminated and no accidents have
occurred since the SFAR's implementation. Environmentalist groups,
however, state that while SFAR 50-2 has improved natural quiet in the
front country, erosion of natural quiet is occurring in the
backcountry. According to these commenters, Notice 96-11 does not bring
GCNP into compliance with Public Law 100-91.
FAA Response: Notwithstanding the value of SFAR 50-2, this
regulatory action responds to a clear legislative mandate to
substantially restore natural quiet, expressed in Public Law 100-91. As
discussed in Notice 96-11, the NPS Report to Congress was based on a
number of studies evaluating whether SFAR 50-2 resulted in a
substantial restoration of natural quiet. NPS found that, while flight-
free zones have helped to limit the areas where aircraft are audible,
aircraft of all types are still audible for some percentage of the time
at virtually all areas where sound data were collected. NPS also found
a correlation between the percentage of time that aircraft are audible
and how visitors feel about aircraft sound. Even when aircraft are
audible for relatively low percentages of the time, some visitors
notice the aircraft and believe that the sound has interfered with
their appreciation of natural quiet. Finally, in its Report to
Congress, the NPS indicated that if no changes are made to SFAR 50-2,
progress to date in the restoration of natural quiet will be lost due
to an increase in air tour operations. An NPS analysis using 1989 FAA
survey data of commercial sightseeing route activity indicated that 43
percent of GCNP met the NPS criterion for substantially restoring
natural quiet. However, a subsequent NPS analysis using 1995 FAA survey
data indicated that 31 percent of GCNP met the NPS criterion for
substantially restoring natural quiet. These findings led the NPS to
conclude that the noise mitigation benefits of SFAR 50-2 are being
significantly eroded.
These findings indicate that the current SFAR was not sufficiently
adequate in substantially restoring the natural quiet to GCNP. The FAA
believes that further regulatory action is therefore necessary to best
ensure the substantial restoration of the natural quiet as called for
by Public Law 100-91. Additionally, substantial restoration of natural
quiet will be further advanced by the NPRM and Notice of Availability
of Proposed Commercial Air Tour Routes for Grand Canyon National Park

[[Page 69308]]

and the Comprehensive Noise Management Plan.

Restoration of Natural Quiet

While some commenters are concerned that the proposed action goes
too far in regulating the air tour industry in order to satisfy a small
group of park users, others believe that it does not go far enough.
Some commenters state that the proposal, at best, would only modestly
improve natural quiet. Other comments are concerned that
``overregulation'' in this instance would set a precedent for national
parks all over the country.
Another commenter states that the proposal would not achieve the
goal of Public Law 100-91 because it would not meet the NPS definition
of ``natural quiet.'' According to some commenters the NPS definition
of ``substantial restoration of natural quiet'' is not supported by
Public Law 100-91 or the Congressional record. According to these
commenters NPS has separated the concept of ``natural quiet'' from
complaints from park visitors by making ``natural quiet'' a park
resource that must be protected whether noise is disturbing park
visitors or not. These commenters object to the NPS definition and to
using it as a justification for rulemaking. One commenter states that
the FAA is on record as having concerns about the NPS definition and
recommends withdrawal of Notice 96-11 until the FAA develops a proposed
definition and invites comment.
One commenter finds the NPS definition too liberal since it allows
half the park to be noisy 25 percent of the day and the other half 100
percent of the day. A presenter at the Congressional hearing says that
the intent of Public Law 100-91 was to restore the natural quiet within
the flight-free zones only and not the entire park.
The Grand Canyon Air Tour Council (GCATC), which represents a
number of air tour operators, states that, because the proposed
restrictions do not apply to NPS-operated and other non-tour aircraft
(e.g., military, Native American reservations), these aircraft could
consume the entire 25 percent audible aircraft cap as defined in
``substantial restoration of natural quiet.'' Thus, air tour operators
would be even further restricted.
FAA Response: The NPS defined ``natural quiet'' and identified it
as a natural resource in its 1986 ``Aircraft Management Plan
Environmental Assessment for Grand Canyon National Park'' which
underwent extensive public review in 1986 (i.e., ``the absence of man-
made sounds * * * considered a natural resource''). The term was
subsequently discussed in numerous public documents, which have also
undergone public review, including NPS Management Policies (1988), and
the Advance Notice of Proposed Rulemaking (ANPRM) concerning
Overflights of Units of the National Park System published in the
Federal Register on March 17, 1994.
The authority of the NPS to define the ``substantial restoration of
natural quiet'' is recognized in Public Law 100-91, Public Law 102-581,
and in the general authorities of the NPS. The NPS's Management
Policies (1988, page 1:3) states that the terms ``park resources and
values'' refer to the ``full spectrum of tangible and intangible
attributes'', including ``intangible qualities'' such as natural quiet,
for which parks have been established and are being managed. National
park areas are set aside to preserve their resources as well as their
special qualities and experiences unimpaired for the enjoyment of
present and future generations. The NPS has the authority and
responsibility to manage these areas, including their resources, values
and visitors.
The NPS definition of ``substantial restoration of natural quiet''
involves time, area, and acoustic components. Because many park
visitors typically spend limited time in particular sound environments
during specific park visits, the amount of aircraft noise present
during those specific time periods can have great implications for the
visitor's opportunity to experience natural quiet in those particular
times and spaces. Those visitors with longer exposures, such as
backcountry and river users, have more opportunity to experience a
greater variety of natural ambient and aircraft sound conditions, but
typically they move through a number of sound environments. Based on
its studies, the NPS concluded that the visitors' opportunity to
experience natural quiet during their visits and the extent of noise
impact depends on a number of factors. These factors include the number
of flights, the sound levels of those aircraft, as well as other sound
sources at the natural sound environment, and the duration (or amount
of time) during that visit that aircraft were audible in specific
locations. Integrated measures of noise (such as DNL and Leq) are
commonly used to quantify time varying noises such as are described
above. Most of the FAA's experience has been in assessing noise impacts
in airport and residential environments where people are exposed to a
variety of sound conditions in the same basic sound environment over a
very long period of time. However, because park environments and the
set of conditions typically experienced by park visitors is completely
different, the NPS concluded that these integrated measures were, by
themselves, inadequate to represent the effect of overflights on park
environments and a person's visit. However, the FAA and the NPS agree
that Leq integrated over a short time period correlates with park
visits and can be useful in assessing park noise impacts.
This action only considers the air tour contribution to the GCNP
noise. In other words, noise contributed from other sources is treated
separately for purposes of noise modeling analysis.
The NPS will continue to strictly control its rescue, law
enforcement, maintenance and critical resource management overflights
to minimize their number and effect on park resources and visitors.
These flights are made for lifesaving and essential management purposes
and will not be a factor in any restrictions on air tour operations.

Discrimination Against Air Tourists vs. Other Users

A number of commenters state that SFAR 50-2 and Notice 96-11
discriminate against air tour visitors to the park, who have little
environmental impact on the park, while ignoring the noise, litter, and
pollution problems associated with ground users. A few commenters
believe that NPS is purposely trying to eliminate air tours from the
park. Other commenters point out that air tour visitors are not being
discriminated against since all commercial enterprises that use the
Grand Canyon are restricted.
FAA Response: The FAA does not agree. The actions by the FAA in
addressing mitigation measures associated with noise from commercial
air tour operations is additive to actions being taken by the NPS to
preserve and protect for future generations the resources of GCNP.
Recent actions include the development of a General Management Plan
which will greatly restrict automobile use in congested rim areas,
provide high occupancy public transit, and establish pedestrian and
bicycle trails. Other actions have included restrictions on the
operation of diesel buses, on diesel and steam locomotives serving the
park, and on outboard engines on river rafts. In addition, the NPS has
a long standing administrative practice in the control and mitigation
of impacts to resources resulting from visitation through the use of
reservation systems for campgrounds and other sites both on the rim and
in the inner canyon, as well as providing for times when use types are
restricted,

[[Page 69309]]

such as the ``oar only'' season for rafting on the Colorado River. As
such, use allocation is a common practice within NPS areas in order to
meet the demands of the general provisions of acts relating to the
administration of National Park Service Areas (16 U.S.C. 1 et seq.) as
well as specific park legislation such as Public Law 100-91.
Further, it was not the intent of Public Law 100-91 to ban aircraft
from overflying the Grand Canyon. In this regard, the FAA believes that
viewing of the canyon from the air is a legitimate and valuable means
of appreciating the beauty of the Grand Canyon. This policy is
supported by the legislative history of Public Law 100-91 and the
objectives states by DOI in its December 1987 recommendations to the
FAA. The agency further believes that the resources of the canyon can
be protected without an exclusion of aircraft, which would have a major
adverse impact on air travel through this area of the southwest. It is
the intent of the rule adopted to permit the continuation of aerial
viewing of the canyon, and air travel through the area, in a manner
consistent with the stated purposes of section 3 of Public Law 100-91
to substantially restore the natural quiet of the Grand Canyon within
the boundaries of the national park.
The NPS has had a consistent position for years regarding air tours
at the Grand Canyon. As stated on page 184 of the 1994 NPS Report to
Congress, one of the six management objectives for the park is:
``Provide a quality aerial viewing experience while protecting park
resources (including natural quiet) and minimizing conflicts with other
park visitors.''

Number of Operators and Operator Fees

An environmentalist group states that one third of the Grand Canyon
air tour operators dodge fees and that air tour numbers may be twice
those reported. Another commenter stated that tribes in the GCNP
vicinity should be able to regulate and collect fees for the airspace
on their lands as the NPS does.
FAA Response: Fee collection is beyond the scope of Notice 96-11.
Through the 1993 Omnibus Budget Reconciliation Act, Congressional
action required the NPS to collect a commercial tour use fee of $25 for
aircraft with 25 seats or less and $50 for aircraft with more than 25
seats. Collection and enforcement of this fee is the responsibility of
the NPS and the NPS can use all information available to assure that
fees are collected in accordance with the law. Nevertheless, payment of
fees has no direct relationship to this rule. Regarding the collection
of fees by Native Americans, Congressional action would be required to
authorize the collection of an overflight fee.

Noise Level Surveys, Monitoring, Studies, and Modeling

Some commenters state that the NPS overstated the impact of air
tour overflights on park visitors in its 1992 visitor survey. For
example, the commenter noted that backcountry users do not venture out
of the Bright Angel Flight-free Zone, and some complaints were
collected at a time when an aerial search was being made for an escaped
convict and NPS service flights were on-going. Furthermore, the
commenters complained that the NPS made no attempt to distinguish what
type of flights were causing the annoyance.
Other commenters state that the NPS-solicited surveys show an
unusually high number of complaints because more complaints are
received from solicited surveys than from unsolicited reports.
Another commenter says that some of the survey questions were
biased because they used the word ``noise'' instead of ``sound'' (e.g.,
visitor perceptions of aircraft noise versus aircraft sound).
Industry commenters also express doubts about the noise monitoring
studies contracted by the NPS. Several commenters state that monitoring
sites were directly under, or in close proximity to, the tour routes
flown by air tour operators as directed by SFAR 50-2.
Several commenters state that although Public Law 100-91 directed
the NPS to distinguish between the impacts caused by sightseeing
aircraft and other types of aircraft, the noise monitoring results do
not distinguish the amount of noise attributable to different types of
aircraft.
Industry commenters also object to the NPS model for noise. One
commenter states that the noise model used for establishing predicted
aircraft noise impacts eliminated the coefficient of lateral over-the-
ground attenuation. BIA states that the NPS established no baseline
other than ambient sound levels, which does not differentiate among the
impacts on visitors from different types of flights. Another commenter
states that the noise analysis is flawed because it was based on NPS
estimates of fleet sizes, aircraft use levels, and certificated noise
levels for aircraft in that fleet, which do not necessarily indicate
the actual noise an aircraft will produce in flight.
FAA Response: The NPS noise level surveys, dose-response studies,
and acoustic modeling were conducted by internationally-respected
acoustical research firms known for the quality of their work. These
firms advised the agency on the design, analysis, and conduct of these
surveys and studies. The NPS consulted extensively with these firms to
ensure that the conclusions in the NPS report to Congress were drawn
directly from study results. The studies were based on standard
research methodologies, including statistically valid random samples,
and have been reviewed by scientists not affiliated with the NPS or the
FAA. They represent the only large-scale, scientifically sound studies
of park noise environments and park visitor reactions to aircraft noise
in outdoor recreation settings.
Acoustic modeling is the accepted approach for addressing noise
concerns over large areas such as Grand Canyon. Noise level
measurements only reflect individual site conditions but can be
productively used to improve the accuracy of the modeling. Both the FAA
and NPS used a standard aircraft noise database and made adjustments
based on actual field measurements. The measured ambient background
sound levels (the baseline for natural quiet taken from Grand Canyon
noise level measurements) were factored into FAA and NPS modeling
efforts, and both models were able to factor in terrain effects, albeit
to different extents. Finally, data from an FAA survey of air tour
operators was used by both agencies to provide the aircraft types,
numbers, and routes used in the acoustic modeling. Although the FAA and
NPS noise models are quite different, the FAA found sufficient
convergence in modeling results to suggest that valid conclusions can
be drawn from both models.
NPS acoustic measurements found that the sound of aircraft was
measurable for some part of the time at virtually all areas where sound
data was collected, including a wide variety of locations and
environments well within the flight-free zones as well as near the
flight routes. This is consistent with NPS modeling which suggested
that aircraft sound can carry 13-16 miles in the eastern end of the
Canyon and even further on the western end--enough to fully penetrate
to the center of every flight-free zone created by SFAR 50-2.
Results from the 1992 survey show that almost 75 percent of fall
backcountry and river oar visitors who heard aircraft responded that
they were moderately to extremely annoyed (NPS Report to Congress, Page
139). The NPS

[[Page 69310]]

did not anticipate this level of annoyance from groups supposedly
protected by the SFAR and was an important indication to the NPS that
additional action was needed to protect quiet in the park. For all
categories of visitors, the stronger category ``interference,'' was
selected more frequently than the weaker category, ``annoyance.'' Of
the visitors who heard aircraft, over 90 percent of fall backcountry
visitors and 100 percent of river oar visitors responded that aircraft
noise interfered with their appreciation of natural quiet (NPS Report
to Congress, Page 192). Both the dose-response study and the survey
found visitor results varied by activity and site.
Aircraft noise is the subject of the second largest number of
complaints in the park. Complaints are an indicator that a problem may
exist, but scientifically valid surveys have been consistently shown to
be necessary to accurately measure visitor reactions.
The NPS found that noise from the air tour routes in place under
SFAR 50-2 is clearly audible (and was measured) from many locations
within Flight-free zones, accounting for the results cited by some
commenters. The search for the escaped convict referred to did not
affect the study which was suspended during that period.
NPS-contracted acoustic monitoring was conducted with a technician
recording the type of aircraft observed and measured. The tour flights
all occurred on standard routes and altitudes and were easy to separate
from any other aircraft, such as NPS flights and high altitude
commercial jets. In fact, pages 187-188 of the NPS report to Congress
provide a breakdown of the amount of time aircraft were audible by
aircraft type during the study, and also show the variety of sites both
within flight-free zones and under or near flight corridors.
In the NPS deliberations that led to development of the survey
questions the question of inducing bias by the use of terms, or by the
wording or sequence of questions, was very carefully considered and
tested before the study. The term ``noise'' was used in the survey
questionnaires very carefully to allow correlations with the large body
of aircraft noise research conducted primarily in airport environs. The
term ``sound'' was used where possible, and the analysis of the
responses suggested that the terms did not affect the results.
The data and the modeling on which the proposed rule is based are
scientifically valid and the best available. The monitoring program
resulting from this rule will also provide additional data which will
help to further validate and refine the modeling.
In formulating the Comprehensive Noise Management Plan for GCNP,
the FAA and the NPS expect to conduct further research regarding
visitors' reactions to noise and natural quiet issues to validate the
current studies and the two agencies' respective modeling systems.

Section-by-Section Discussion of Final Rule

The following is a brief summary of the major proposals, and the
comments, received. The FAA's response to those comments and the final
rule action follow.

Section 93.301 Applicability

Proposed Sec. 93.301 described the lateral and vertical dimensions
of the SFRA. Notice 96-11 solicited comments on modifying the
dimensions of the SFRA by extending the SFRA north-northeast of the
confluence of the Little Colorado and Colorado Rivers; extending the
SFRA southward below the Bright Angel and Desert View Flight-free
Zones; extending the SFRA at the western edge to cover that portion of
the Grand Wash Cliffs in the park that was inadvertently omitted from
the 1987 NPS Grand Canyon Aircraft Management Recommendation and the
original rule; and increasing the altitude of the SFRA ceiling from
14,499 to 17,999 feet MSL.

Comments

Heli USA states that the revised SFRA could affect access to the
Grand Canyon West airport.
An individual from the Navajo Area Office of the BIA says that the
extension of the SFRA to the north-northeast of the Little Colorado and
Colorado Rivers would introduce air traffic into an area outside the
current SFRA, over the Marble Canyon and Navajo land, which did not
have traffic before.
The Experimental Aircraft Association (EAA), the General Aviation
Manufacturers Association (GAMA), and the Aircraft Owners and Pilots
Association (AOPA) object to the proposed extension of the SFRA
ceiling. EAA states that the FAA has not presented any information
showing that any commercial sightseeing aircraft are using or plan to
use these altitudes. GAMA says that requiring turbo-charged piston-
engine and turboprop turbine-powered aircraft that have optimum
operating altitudes between 14,500 and 17,000 feet to take alternate
routes around the SFRA will add considerable costs to implementing the
rule. AOPA says that the proposed requirement is discriminatory towards
general aviation because it forces all general aviation flights over
the Grand Canyon to take place at a higher altitude than flights by
commercial air tour operators.
Another commenter says that Notice 96-11 is counter to FAA's
General Aviation Policy Statement (adopted by the FAA Administrator in
1995), which calls for fostering general aviation and maintaining
safety through voluntary compliance and other means to reduce the
regulatory burden on general aviation.
Another commenter contends that Notice 96-11 will impact many other
aircraft who operate across Northern Arizona between 14,500 MSL and the
base of Class A airspace under VFR. The commenter adds that increasing
the SFRA altitude would make it impossible to fly over the SFRA without
obtaining an ATC clearance to operate in Class A airspace.
The Soaring Society of America, Inc. (SSA) opposes the proposed
rule as it applies to quiet and unobtrusive civil aircraft such as
sailplanes and gliders. Since airplane and helicopter sightseeing
overflights are the perceived cause of the noise problem in the Grand
Canyon, the SSA believes the regulations should be tailored
specifically toward such aircraft and the FAA should permit sailplanes
and gliders to continue to operate under the current SFAR 50-2. SSA
refers to the Department of the Interior's Report on Effects of
Aircraft overflights on the National Park System which suggests to that
society that sailplane ``noise'' is approximately equal to daytime
ambient noise, therefore nothing will be gained by burdening sailplanes
and gliders with the proposed rule.
FAA Response and Final Rule Action: In 1989, the FAA revised the
southern boundaries of the SFRA in the West Canyon area to establish a
corridor to the Grand Canyon West Canyon Airport. This corridor was
designed to permit access to the airport to assist the economic
development of the Hualapai tribes. Nothing in this final rule modifies
the corridor that was established in 1989. The FAA will reserve its
response to comments regarding specific routes until after the comment
period closes for the Notice of Proposed Routes.
Increasing the SFRA ceiling from 14,499 feet MSL upward to but not
including 18,000 feet MSL is intended to prevent commercial sightseeing
operators from circumventing the intent of this rule by overflying the
fly free zones between 14,500 feet MSL and 17,999 feet MSL.

[[Page 69311]]

The upward expansion of the SFRA does not impose a barrier to
general aviation aircraft. The effect of the expansion is to regulate
commercial sightseeing flight operations pursuant to Sec. 93.315 which
permits only those operations authorized in operations specifications.
The Grand Canyon attracts an unusual level of air traffic. The FAA
continues to be concerned that safety could be impacted by the
concentration of air traffic, including powered and nonpowered aircraft
over GCNP. Therefore, it opts not to relax SFRA operating requirements
for sailplanes and gliders. The FAA adopts the SFRA as proposed.

Section 93.305 Flight-Free Zones and Flight Corridors

Proposed Sec. 93.305 described the lateral and vertical dimensions
of the proposed flight-free zones; proposed creating two new flight-
free zones: The Sanup Flight-free Zone and the Marble Canyon Flight-
free Zone; proposed merging the Toroweap/Thunder River and Shinumo
Flight-free Zones and extending this zone to the park boundary;
proposed expanding Desert View Flight-free Zone to the north and east
to the GCNP boundary; and proposed extending the current Bright Angel
Flight-free Zone to the north to the GCNP boundary.
Proposed Sec. 93.305 also described the five flight corridors that
allow access through the canyon area for general aviation and transient
operations and routes for commercial sightseeing flights.
The FAA proposed to add two new flight corridors in the proposed
Marble Canyon Flight-free Zone. In addition, the FAA proposed to close
the Fossil Canyon Corridor, extend the Zuni Point Corridor into a Y-
shape in the north, and shift the southern portion of Dragon Corridor
to the west. The FAA also proposed that commercial sightseeing aircraft
would be allowed to operate in only one direction in the Zuni Point
Corridor.

General Comments on Flight-free Zones and Flight Corridors

Safety Comments: Several commenters express concerns about safety
if the proposed rule is implemented. According to these commenters, the
combination of restricted corridors, changes in route structure, and
curfews would increase the density of aircraft in the available
airspace, thereby increasing the potential for a mid-air collision.
The NTSB commented that the compression of air traffic into smaller
airspace would limit safe maneuverability in marginal weather
conditions, funnel air traffic into fewer routes, and in some areas,
compress slower single-engine airplanes, helicopters, and higher
performance airplanes into the same airspace. This would increase the
likelihood of midair collisions in GCNP. The NTSB adds that the FAA
should systematically analyze the possible effects of the proposed
changes on air safety and ensure that these results are considered
before adopting the proposal.
One commenter disagrees with the claim that the proposed rule would
create an unsafe environment. The commenter points to the FAA's 1995
Report to Congress, ``Report on the Study on Increased Air Traffic over
Grand Canyon National Park,'' which states that it would be highly
unlikely that operations would ever approach saturation level. The
commenter also points out that the proposed rule allows pilots to make
evasive flight maneuvers necessary to maintain safety.
General Aviation: One commenter objects to the proposed flight-free
zones because they will effectively ban general aviation from flying
over the park. The average general aviation aircraft is not equipped to
operate at the minimum altitudes required by the proposal. According to
the commenter, the proposed new flight-free areas will prohibit general
aviation aircraft from flying directly from Las Vegas to either
Albuquerque or Farmington. The commenter asks that general aviation
aircraft be allowed to overfly the flight-free areas at altitudes above
10,499 MSL.
Native American Tribal Lands: In a statement given at the
Congressional hearing, representatives of the Havasupai Tribe say that
a foreseeable result of the proposed changes will push overflights
south of GCNP resulting in adverse environmental effects. In a comment
subsequently submitted to the docket, representatives of this Tribe say
that while reducing the negative impacts of overflights by regulating
the airspace within the park is worthwhile, the result will be to
increase aircraft noise outside the park, including the Havasupai
reservation. The commenter adds that there has been no analysis of the
environmental effects of these regulations outside the park boundaries
and that ``the FAA's unjustified rush to action must be slowed.''
Other General Comments: Two commenters remind the FAA that flight-
free zones are not noise free zones since noise travels 13 to 16 miles;
nor are they entirely flight free since high flying aircraft still
overfly them. These commenters point out that while flight corridors
are necessary, they are not a solution for the noise problem since they
heavily affect several scenic areas in the park, such as Point
Imperial, Nankoweap, Cape Final, Unkar, Hermit, Boucher, and Crystal
Rapids trails.
FAA Response and Final Rule Action: The comments regarding safety
express similar concerns: (1) Flight-free zones require changes to
routes, (2) flight-free zones create smaller available airspace, (3)
the effect of curfews on the density of air traffic, (4) increased
possibility of midair collisions because of route changes and combining
aircraft of differing flight characteristics. Each of these general
areas of concern will be addressed separately.
Flight-free zones require changes to routes: The modified and new
flight-free zones are necessary to comply with the mandate of Public
Law 100-91 to achieve substantial restoration of the natural quiet in
GCNP. One of the primary responsibilities of the Las Vegas Flight
Standards District Office (FSDO), through a special unit, is to provide
oversight of the commercial sightseeing operators in the Grand Canyon.
The members of this unit are all highly experienced with this subject
and have worked closely with the commercial sightseeing operators and
the NPS. The Notice of Availability of Proposed Air Tour Routes of GCNP
(Notice of Proposed Routes), which is published simultaneously with
this final rule, explains how interested persons may obtain detailed
information on the routes. The FAA will review the comments received
from the public related to the notice of proposed routes and if
appropriate, make modifications to the routes.
Flight free zones create smaller available airspace: The FAA agrees
with the NTSB that the additional flight-free zones create a smaller
airspace for air tour aircraft. The NTSB is concerned that the smaller
airspace may limit ``safe maneuverability in marginal weather
conditions.'' As in SFAR 50-2, the FAA has specifically included
language in Sec. 93.305, Flight-free zones, that will allow air tour
aircraft to fly within the flight-free zones ``in an emergency or if
otherwise necessary for safety of flight.'' The intent of this language
is to allow flight into a flight-free zone for any safety reason
including emergencies. This language will also enable pilots to deviate
from course to avoid other aircraft and unsafe weather conditions. This
provision will be liberally construed when applied in the interests of
safety. This should resolve any concern about the ability of an
aircraft to maneuver in a smaller available

[[Page 69312]]

airspace. Additionally, the FAA agrees with a commenter that the
airspace has not approached any unsafe saturation level.
The effect of curfews on the density of air traffic: The FAA agrees
that curfews on the west end of GCNP might create a situation whereby
large numbers of aircraft could attempt to enter the air tour routes at
the same time and along the same routes. Based on the FAA's safety
analysis of the air tour flights originating from the Las Vegas area,
the FAA has decided to exempt the routes beginning on the western end
of the park from any curfew.
However, Sec. 93.316(a) prescribes a fixed curfew. Specifically, no
person shall conduct commercial sightseeing operations within the
Dragon and Zuni Corridors during the following periods. (1) Summer
season (May 1-September 30)--6 p.m. to 8 a.m. daily; and (2) Winter
season (October 1-April 30)--5 p.m. to 9 a.m. daily. (See discussion
later in the document.)
Increased possibility of midair collisions because of the changes
and combining aircraft of differing flight characteristics: In light of
these concerns the FAA will change the flow of traffic along the routes
on the eastern side of the park (e.g., Dragon corridor) to a clockwise
direction. This change will prevent conflict with aircraft merging from
other existing and proposed routes. Also, the clockwise direction was
designed for other safety reasons. (See discussion/response on Zuni
Corridor.) More detail is contained in the Notice of Proposed Routes
that is being published simultaneously with this final rule. Regarding
combining aircraft of differing flight characteristics, the FAA will
continue its practice of separating fixed-wing aircraft from rotary-
wing aircraft through altitude restrictions. Experience, cooperation,
and a proactive partnership developed between the commercial
sightseeing operators and the FAA resulted in flight procedures that
are included in the operator's FAA approved operations manual. The FAA
believes that these established procedures will prevent potential
conflicts.
Likewise, for safety, the rule continues to segregate commercial
sightseeing operations from general aviation/transient operations in
the SFRA. Commercial operators, under their operations specifications,
are held to a higher operational proficiency standard that addresses
the complexities of the route systems, terrain, flight corridors,
weather norms, etc. It would be unrealistic to impose an equally high
proficiency standard for the occasional general aviation pilot.
Therefore, the FAA continues to believe that it is necessary to
segregate these communities of operators.

General Comments on Commercial Air Tour Routes

Several commenters state that it is difficult to comment on the
effects of the proposed changes since the proposed routes are not
included in Notice 96-11. Nevertheless, the FAA received some general
comments on potential route changes. Twin Otter says that the FAA has
not proposed one quieter aircraft route, even though the NPS had
proposed, in its Report to Congress, that some flight tour routes be
restricted to ``quiet aircraft only.''
Southwest Safaris says the helicopter operations have been given
preferential treatment by the FAA. They are allowed to fly from 500 to
1,500 feet lower than fixed-wing aircraft and to fly shorter routes in
the middle of the park. According to the commenter, helicopter tours
are on the rise and constitute much of the noise problem.
FAA Response and Final Rule Action: The FAA agrees with the
comments that the operators should have an opportunity to comment on
proposed routes. Simultaneously with this final rule, the FAA is
publishing a Notice of Proposed Routes, which includes the proposed
tour routes within the Grand Canyon. Operators will have an opportunity
to comment on the proposed routes. The FAA will reserve its response to
comments regarding specific routes until after the comment period
closes for the Notice of Proposed Routes.
Regarding routes for ``quiet aircraft,'' simultaneously with the
final rule, the FAA is publishing an NPRM, Noise Limitations for
Aircraft Operations in the Vicinity of the Grand Canyon National Park,
which proposes certain routes that will be limited to noise efficient
aircraft only.
The FAA disagrees with the comment that helicopter operations have
been given preferential treatment. Regarding altitude, the FAA's long-
standing policy is to separate helicopters and fixed-wing aircraft
because the two classes of aircraft generally have vastly different
flight characteristics. Traditionally helicopters, normally slower and
more maneuverable than fixed-wing aircraft, have been allowed to fly
lower. The FAA intends to continue this safety rationale.

Comments on Marble Canyon Flight-free Zone--Navajo Bridge and North
Canyon Corridors

Three commenters support the Marble Canyon Flight-free Zone. The
Sierra Club-Grand Canyon Chapter states that the flight-free zone would
be of particular benefit, particularly to fishers and river runners,
and believes that the rim rather than the river bank should be the
eastern boundary of the flight-free zone.
Another commenter suggests that the proposed Marble Canyon Flight-
free Zone be modified to protect significant locations such as Blue
Spring or other sacred places in the Little Colorado vicinity. Also,
according to the commenter, no flights should be allowed over popular
side canyon attractions such as North Canyon, South Canyon, Silver
Grotto, and Saddle Canyon.
EAA states that the top of all three sections of this flight-free
zone should be reduced from 14,000 to 8,500 feet MSL to allow general
aviation flights between Las Vegas, Nevada and Farmington, New Mexico.
Twin Otter states that the flight-free zone is too small to be
meaningful and would eliminate a popular air tour route.
FAA Response and Final Rule Action: The FAA has reconsidered its
proposal for the Marble Canyon flight-free zone in light of the
comments received. The FAA has determined that the proposed flight-free
zone would provide only a minimal noise mitigation benefit because of
the narrow dimensions. In addition, the FAA agrees that the proposed
zone could have impacted general aviation flights between Las Vegas and
Farmington. Therefore, the final rule eliminates the Marble Canyon
Flight-free Zone.
However, the FAA is modifying the minimum sector altitude for this
area. (See discussion under Sec. 93.307, Minimum Flight Altitudes.)

Comments on Desert View Flight-free Zone and Zuni Point Corridor

Several commenters state that making Zuni Point Corridor one-way
may present safety problems due to inclement weather and unexpected
weather changes in the north canyon. GCATA states that because of the
lack of a weather reporting station on the north rim, tour pilots
proceeding through the Zuni Point Corridor will be required to make
weather decisions in the vicinity of the ``Y'' on what direction to
proceed.
Papillon states that the noise problem over the area between the
Little Colorado River confluence and Imperial Point has been
exacerbated by the piston-driven single and multiengine six to nine
passenger airplanes. To clear the north rim, these airplanes climb.
When entering the canyon via Zuni Point

[[Page 69313]]

Corridor, these types of airplanes should enter at a higher level, thus
eliminating the noisy climb configuration.
The Sierra Club-Grand Canyon Chapter supports the enlargement of
the Desert View Flight-free Zone (as does NPCA) but states that the
Zuni Northwest Corridor cuts though the Critical Noise Sensitive Area
that has Point Imperial at its center. This corridor is also a problem
for users of the Saddle Mountain-Nankoweap Basin area. The Sierra Club-
Angeles Chapter believes that the proposal should close Zuni Point
Corridor because it impacts at least six trails, four permanent stream
basins, important archaeological and historical sites, and Papago
Point, the only major point on the south rim where one could formerly
find solitude and escape the sounds of auto traffic.
FAA Response and Final Rule Action: Concurrent with the publication
of this final rule, the FAA is publishing a Notice of Proposed Routes
discussing route structures and directions of flights. The FAA will
consider pertinent comments received in response to Notice 96-11
regarding routes, as well as any additional comments submitted in
response to the Notice of Proposed Routes. In response to the perceived
safety problems regarding weather, the FAA will route traffic in a
clockwise fashion through the Dragon and Zuni Corridors. This flow will
allow operators to better observe weather conditions around the North
Rim so as to avoid encountering adverse weather condition in the
vicinity of the North Rim, e.g., high winds, low visibility,
turbulence, etc. The FAA believes this flow will enhance safety by
pilots having the opportunity to take appropriate actions to avoid
these conditions. Noise mitigation will be an additional benefit, as
aircraft will no longer be climbing as they pass near Point Imperial.

Comments on Bright Angel Flight-free Zone, Zuni Point, and Dragon
Corridors

NPCA notes that the NPS has estimated that the one-way
restructuring of the Zuni Point Corridor will add 3,800 operations into
the Dragon Corridor. Some commenters object to the northern extension
of Bright Angel Flight-free Zone. Two other commenters say that the
northern extension will lengthen the distance of the Grand Discovery
Tour by 20 percent, which will increase operator costs and require
operators to fly over the highest points of the north rim, resulting in
frequent weather cancellations.
The Sierra Club-Grand Canyon Chapter supports the enlargement of
the Bright Angel Flight-free Zone. Twin Otter and Grand Canyon Airlines
recommend that the Dragon Corridor be converted within 2 years to a
quiet airplane flight corridor. The commenters also recommend that the
FAA define what operating characteristics an airplane model must have
in order for it to conduct round-trip air tours within Dragon Corridor
and then immediately permit such fixed-wing air tours within this
corridor (just as the FAA now permits out-and-back helicopter tours).
Grand Canyon Airlines states that SFAR 50-2 management policies
have encouraged rotorcraft operators to concentrate on Dragon Corridor
tours. Since 1994, when helicopter operators began concentrating their
tours within the Dragon Corridor, Grand Canyon Airlines has conducted
35 percent fewer air tours in this area. This commenter wants to be
permitted to conduct similar round-trip Dragon Corridor tours to remain
competitive if the FAA adopts the extension of the north rim air tour
route.
Grand Canyon River Guides believes that the out-and-back helicopter
route into Dragon Corridor should be abolished. This route allows
helicopters to offer a shorter trip which is similar in cost to the
least expensive tour of the larger, quieter fixed wing operators which
carry more people with much less impact. According to the commenter,
this shorter route is causing a very negative trend as noticed by the
increased helicopter traffic on the Dragon Corridor with each passing
year.
NATA is pleased that Notice 96-11 establishes the dog-leg within
the Dragon Corridor because it would route air traffic away from the
only location on the rim of the canyon where air tours and ground
visitors interact. Papillon also agrees with the proposed change to
relocate the south end of Dragon Corridor to the west.
USATA contends that the current routes that air tour operators fly
encompass only 17 percent of the entire park. With the Dragon Corridor
``dog leg,'' the front country areas of the park (where 99 percent of
all ground users visit) would be 100 percent protected from air tour
noise. If flights were to double or even quadruple, one could expect
the number of aircraft seen or heard to remain well within reason at a
maximum of less than one aircraft per hour.
The Sierra Club--Grand Canyon Chapter, NPCA, and Grand Canyon River
Guides do not support the changes to Bright Angel and Toroweap-Shinumo
Flight-free Zones to accommodate the Dragon Corridor dog leg. They
argue that these changes would degrade a portion of the park on the
south rim that is currently relatively quiet. This area includes
Havasupai Point. The Sierra Club suggests extension of the southwest
corner of the Bright Angel Flight-free Zone (from 36 deg.09'31'' N,
112 deg.11'15'' W; to approximately 36 deg.02'35'' N, 112 deg.14'30''
W; then southeast along the GCNP boundary).
The Sierra Club also points out that the seventh point
(36 deg.01'16'' N, 112 deg.11'39'' W) should be approximately
36 deg.00'58'' N, 112 deg.11'45'' W.
AOPA says that changes to the Dragon Corridor could make navigation
extremely difficult and increase the chance that a pilot could
inadvertently transgress into a flight-free zone.
FAA Response and Final Rule Action: Flight-free zones are being
expanded and/or modified to aid the substantial restoration of the
natural quiet, as mandated by Public Law 100-91. As stated by Senator
John McCain in the legislative history of Public Law 100-91:
The purpose of flight-free areas is to provide a location where
visitors can experience the park essentially free from aircraft-sound
intrusions. The boundaries of these flight-free zones are meant to be
drawn to maximize protection to the backcountry users and other
sensitive park resources. The extent of these areas should be adequate
to ensure that sound from aircraft traveling adjacent to these zones is
not detectable from most locations within the zones. It is within these
zones that we expect to achieve the substantial restoration of the
natural quiet. (Congressional Record--Senate, p. S10799, July 28,
1987).
The FAA agrees that there should be incentives for operators to
convert to noise efficient aircraft in the Dragon Corridor; those
incentives are addressed in the NPRM being published simultaneously
with this final rule.
The FAA agrees with the Sierra Club that the Bright Angel Flight-
free Zone boundary description is incorrect, and corrects it in this
action.
The FAA has adopted the proposed shift to the west in the Dragon
Corridor (the ``dog-leg'') because it provides important noise
mitigation to the Hermit's Basin Region and presents no safety
concerns. This action responds to requests made by both the majority of
the operators and NPS. By leaving the Dragon Corridor open, this action
maintains certain viable commercial sightseeing routes over the canyon
while providing greater noise mitigation in other parts of the park
from larger flight-free zones. The legislative history of Public Law
100-91 indicates that it was not the intent of the legislation to

[[Page 69314]]

ban aircraft from overflying the Grand Canyon.
The change is consistent with the 1987 NPS recommendation and
responds to comments made at the Flagstaff public meeting. These
changes provide for noise mitigation while supporting a viable industry
at the eastern end of the canyon.
The corridors will remain 2 nautical miles wide for commercial
sightseeing operations and 4 nautical miles wide for general aviation
and transient operations. The addition of a bend or ``dog-leg'' in the
Dragon Corridor will make navigating the corridor a bit more involved
but will be manageable. The revised Grand Canyon VFR Aeronautical Chart
will contain latitude/longitude and VFR check points to assist pilots
navigating in the area. Specifically, the corridor centerline and
``turn-point'' will be identified electronically via latitude/longitude
coordinates. The ``turn-point'' will be identified by VOR/DME
information from the Grand Canyon VOR. And the corridor and ``turn-
point'' will be identified by topographic features as well.

Comments on Toroweap/Shinumo Flight-free Zone and Tuckup Corridor

Several commenters state that the extension of the Toroweap/Thunder
River Flight-free Zone and the merger of Toroweap/Thunder River with
the Shinumo Flight-free Zone will eliminate certain routes, thus
reducing scenic viewing while extending tour times. One commenter adds
that this extension is meaningless because air tour aircraft diverting
around National Canyon will still be audible since the flight-free
extension is too small for effective noise attenuation.
An individual from the Navajo Area Office of the BIA states that
the expansion of Toroweap/Shinumo Flight-free Zone will block flight
departures on the Brown 3 route from the Bar 10 airstrip which provides
river runner support to the Hualapai Tribe.
Several commenters support expansion of the Toroweap/Shinumo
Flight-free Zone and recommend that it be extended even farther back
from the south rim to reduce the visual and noise intrusions from air
tours. The Sierra Club--Grand Canyon Chapter states this is necessary
to address the concern that air tours will fly just outside the flight-
free zone boundary over the river corridor. They add that the existing
flight-free zone located within a 1.5 nautical mile radius of the
Toroweap overlook is inadequate and should be expanded.
The Sierra Club points out an error in the flight-free zone: the
second point (112 deg.3'19'' W) should be 112 deg.13'19'' W and the
third point (36 deg.02'' N) should be 36 deg.20'02'' N.
FAA Response and Final Rule Action: In analyzing the commenters'
statements on the extension of the southern boundary, the FAA believes
that the commenters are referring to the Blue 1 route. The FAA is
soliciting comments in the NPRM that is published simultaneously with
this rule regarding the feasibility of limiting a portion of the Blue 1
route in the National Canyon to noise efficient aircraft.
In response to comments regarding routes, the FAA will consider
pertinent comments received in response to Notice 96-11, as well as any
additional comments submitted in response to the Notice of Proposed
Routes.
Any further expansion of the Toroweap Flight-free Zone will need to
be considered in the context of the Comprehensive Noise Management
Plan.
The FAA disagrees that the rule will result in an adverse effect on
the safe operation of the Bar 10 airstrip or black river runner
flights.
The FAA agrees with the Sierra Club that the Toroweap/Shinumo
Flight-free Zone boundary description is incorrect, and corrects it in
this action.
The FAA will reserve its response to comments regarding the Brown 3
commercial sightseeing tour route until after the comment period closes
for the Notice of Proposed Routes.

Comments on Sanup Flight-Free Zone

The Sierra Club-Grand Canyon Chapter supports the new Sanup Flight-
free Zone. The chapter suggests that boundaries be changed to give some
protection to the Shivwits Rim and Sanup Plateau.
AOPA states that the new Sanup Flight-free Zone would force an
increase in the minimum enroute altitude for Victor Airway 235 from
10,000 to 14,500 feet MSL between Peach Springs and Mormon Mesa
navigational aids; that portion of the airway would be unusable by
general aviation aircraft. One commenter feels that this increase would
adversely affect safety and cause burdensome requirements for oxygen
equipment because of the increased altitude.
EAA wants the ceiling of the flight-free zone lowered for general
aviation operations from 14,000 to 8,500 MSL. This change would
accommodate general aviation flights between Las Vegas and Albuquerque.
The FAA also received several comments regarding the possible
impacts of the proposed Sanup Flight-free Zone on commercial
sightseeing tour routes.
FAA Response and Final Rule Action: After analyzing the impact on
VFR and IFR traffic, the FAA has adopted the Sanup Flight-free Zone.
However, the vertical limits of the Sanup Flight-free Zone will be at
7,999 feet MSL. This will accommodate general aviation aircraft
operations between Las Vegas and Albuquerque. By lowering the vertical
limit of this flight-free zone, the minimum enroute altitude for V-235
remains unchanged.
In response to comments regarding routes, the FAA will consider
pertinent comments received in response to Notice 96-11, as well as any
additional comments submitted in response to the Notice of Proposed
Routes.

Comments on Elimination of Fossil Corridor

GCATC states that the closure of the Fossil Canyon Corridor could
possibly bring an end to Las Vegas-based air tours of GCNP. Although
the FAA claims that only a low amount of traffic goes through this
corridor, in fact most Las Vegas-based operators conduct air tours over
the Blue 1 route which traverses the Fossil Canyon Corridor and
adjacent lands. If this corridor were to close, the 200-mile air tour
route from Las Vegas to Tusayan would include only approximately 20
miles over less striking portions of the Grand Canyon, including only 4
miles over GCNP. Such a decrease in Grand Canyon overflight would
virtually eliminate the demand for such flights.
The individual from the Navajo Area Office of the BIA says that the
Hualapai Tribe utilizes the Brown 1A route to support river runner
traffic across Kaibab Plateau, which will be eliminated by the closure
of the Fossil Corridor, as will the Blue 1A route be eliminated due to
closure of the Fossil Corridor.
The Sierra Club-Grand Canyon Chapter and Grand Canyon River Guides
support closing the Fossil Canyon Corridor.
FAA Response and Final Rule Action: The FAA recognizes that closing
Fossil Canyon Corridor will affect some air tour routes. However, this
action is necessary to aid in the goal of substantially restoring
natural quiet to the park, as mandated by Public Law 100-91. The FAA
believes, based on its 1995 survey of air tour operators and the routes
that they fly, that Fossil Canyon Corridor is not heavily used for
commercial sightseeing purposes and

[[Page 69315]]

those few operators who use it will have alternate routes available.
In response to comments regarding routes, the FAA will consider
pertinent comments received in response to Notice 96-11, as well as any
additional comments submitted in response to the Notice of Proposed
Routes.

Section 93.307 Minimum Flight Altitudes

Proposed Sec. 93.307 set forth different minimum altitudes in
sectors and corridors for commercial sightseeing operations and
transient and general aviation operations to separate these operations
to the maximum extent practical. Notice 96-11 solicited comments
concerning minimum altitudes for Navajo Bridge Corridor at 5,000 feet
MSL for commercial tour operations and 8,000 feet MSL for general
aviation and transient operations.

Comments on Minimum Flight Altitudes

The Northern California Aviation Users Working Group (NCAUWG) says
that the NPS did not comply with Public Law 100-91 because it did not
establish the ``proper minimum altitude which should be maintained by
aircraft when flying over units of the National Park System.''
Kenai Helicopters, Inc. states that although Notice 96-11 does not
change many of the minimum altitudes through the flight corridors,
serious consideration for lower altitudes, coupled with noise
attenuating flight procedures and maneuvers, should be analyzed in
order to restore quiet in the flight-free zones in the best way.
The Sierra Club-Grand Canyon Chapter states that Notice 96-11 will
not prevent flights below the canyon rim. This commenter suggests that
the minimum flight altitude between Boundary Ridge and Supai be raised
to 10,500 feet MSL to prevent aircraft from flying below the rim at
Point Imperial, and that the FAA verify minimum flight altitudes for
the entire SFRA to prevent below rim flights.
FAA Response and Final Rule Action: The FAA does not agree with
these comments. The NPS Report to Congress concluded that establishing
a simple minimum altitude for aircraft overflights over all units of
the National Park System was neither feasible nor necessary. Instead it
recommended that all reasonable methods and tools be used in issue
resolution: voluntary agreements, quiet aircraft incentives, spatial
zoning, altitude restrictions, operations specifications, and limits on
time of operation. Public Law 100-91 mandated much more than an
appropriate minimum overflight altitude for GCNP. Specifically, section
3 required the FAA to prepare and issue a comprehensive airspace
management plan, which in part provided for provisions prohibiting
below rim flights and designation of flight-free zones. Section 3 of
Public Law 100-91 prohibits the flight of aircraft below the rim of the
Canyon. Consequently, Kenai Helicopters, Inc.'s suggestion is not
appropriate. Finally, the FAA believes the clockwise flow through the
Zuni and Dragon Corridors will preclude aircraft from flying below the
rim at Point Imperial.
In order to simplify the northeast sector of the SFRA, the FAA has
combined the Marble Canyon and the North Canyon sector into one sector
and renamed this section the Marble Canyon Sector. This sector will
have a minimum sector altitude of 8,000 MSL.

Section 93.316 Limitations for Commercial Sightseeing Operations

The FAA proposed several additional methods to help achieve the
objective of restoring natural quiet. One such method was flight-free
periods (curfews). Proposed Sec. 93.316(a) provided for both a fixed
curfew and a variable curfew.

Comments on Fixed and Variable Curfews

A number of commenters (e.g., Twin Otter, HAI, Kenai Helicopters,
an individual from the Navajo Area Office of the BIA) say that curfews
could create significant congestion and safety problems as air tour
operators reschedule aircraft to arrive at the edge of the SFRA at the
same time.
GCATA states that GCNP Airport will have a major traffic problem
with all Las Vegas operators arriving at the same time for one runway
of operations. Also, since all helicopter operators have moved to the
Airport, they will be ready for their initial launch of the business
day. GCATA asks which operator will get priority, and says that the
number of flights could create havoc for the tower operators at the
Airport. Another problem is that all airplanes arrive from the west and
helicopters will be departing on the east side. GCATA asks how the
tower operators would handle this. The commenter believes that the
curfews will push airports to their maximum operation and questions if
this is safe.
According to Las Vegas McCarran Airport, the majority of air tour
operators operate by ``banking'' Grand Canyon air tour flights. In
other words, based on passenger demand during a given period, each
operator departs a number of aircraft more or less simultaneously from
an origin airport to perform Grand Canyon air tours.
This commenter states that, under the fixed curfew, peak operations
in the SFRA are anticipated to occur between 8 a.m. and 10 a.m. Under
the variable curfew, total operations are anticipated to increase
substantially from 9 a.m. through 1 p.m. In addition, for airports in
the Las Vegas region, a total of 60 Grand Canyon air tour operations
would be affected by the proposed fixed curfew, and 99 by the proposed
variable curfew. These aircraft operations would be required to alter
the existing times of operations to non-curfew hours, or operate on the
Blue Direct route, which is not considered an air tour route and not
subject to the restrictions proposed in either curfew alternative.
Several commenters are concerned about the economic impact of
curfews. Heli USA states that the proposed curfews would eliminate 20
percent of its flights and cause severe economic problems.
GCATC says that the FAA's estimate of $6.6 million in annual loss
of revenue, as a result of fixed curfews, is underestimated because:
(1) The FAA states that all losses would be incurred in the summer
season (May 1-September 30), wrongly assuming that all flights during
the winter season (October 1-April 30) can be rescheduled. Although
rescheduling of some winter flights may be possible, the flexibility of
both air tour operators and passengers is limited and, consequently,
not all passenger groups can be accommodated under FAA's proposed
restricted operating hours. (2) The proposed fixed curfew forces air
tour operators to begin tours substantially later and end them
substantially earlier than under the dusk-to-dawn flight period
currently allowed. For some months, the FAA's proposal may shorten
available flight time by 25 to 33 percent, causing operators to lose
multiple flights on a daily basis.
Comments from the Grand Canyon Trust state that the FAA's
assessment of the costs of basic curfews is fundamentally flawed in
that it makes no attempt to anticipate how mismatches between supply
and demand are likely to be resolved in the marketplace. Given that
Grand Canyon tours are once-in-a-lifetime experiences, and that roughly
60 percent of all visitors are foreigners for whom sightseeing tours
are only one part of a more extensive vacation package, consumers are
more likely to be relatively price insensitive, particularly at the
margin. This implies that operators will likely be able to more

[[Page 69316]]

than offset revenue losses resulting from the flight curfews proposed
by the FAA. The commenter suggests that the near-term response of air
tour operators to the regulation is likely to be a modest shift in
prices upward which will allow them to recover the revenues lost due to
canceled flight operations. Over the longer term, operators will be
able to replace their existing aircraft with larger, higher capacity
aircraft, thereby restoring the balance between supply and demand,
gradually bringing down prices and restoring market equilibrium. The
overall impact on the industry will likely be negligible, the commenter
suggests. GCATA states that variable curfews will be unworkable because
operators will not be able to handle advance reservations without
knowing if a corridor will be open or shut.
Papillon states that variable flight-free periods would be
unacceptable because most air tour passengers must fly in the early or
late part of the day and most book their flights 3 to 6 months in
advance. The variable flight-free periods would eliminate approximately
80 percent of the flight revenue of operations originating at the GCNP
Airport.
An individual from the Navajo Area Office of the BIA says that
curfews could create negative impacts to all three Native American
tribes in the GCNP vicinity and recommends a specific exemption to
Native American tribes for any flights sanctioned by such Native
American tribes over their own lands. Alternatively, if tribes'
commercial operations are considered as governmental flights, they
should be exempted from the SFAR restrictions.
The Sierra Club-Grand Canyon Chapter states that intrusive noise is
particularly annoying during the morning and evening hours and that
flight-free hours should not be considered a substitute for actual
restoration of natural quiet. This commenter recommends flight-free
months as well as flight-free periods that would coincide with engine-
free raft periods on the river.
Another commenter states that curfew times should be adjusted
monthly or on a seasonal basis, and that a time of 2 or 3 hours before
sunset would be a better compromise, because tourists particularly
enjoy the canyon rims and along the river in the late afternoon and
evening light.
Two commenters recommend fixed curfews over variable curfews. Grand
Canyon River Guides states that, since the variable curfews would
require further data and analysis that could not be accomplished before
the end of 1996, the proposed rule should focus on fixed curfews. NPCA
believes that variable curfews will take too long to implement. If some
tour operators opt for quiet technology while the monitoring is being
conducted, it will skew the monitoring results and reward those
operators that did not upgrade their equipment. NPCA still supports
noise monitoring in consideration of possible curfews for the
Comprehensive Noise Management Plan. The NPCA thus recommends the
seasonal fixed curfew.
Papillon states that air tours originating in the east end of the
canyon normally commence one hour after sunrise and terminate
approximately one hour before sunset. The commenter states that present
operations basically comply with the proposed fixed curfews and that
for 6 months of the year, there are no flights for more than 80 percent
of the time. Thus, Papillon recommends no fixed curfews for flights
originating out of GCNP airport to the east end of the canyon.
FAA Response and Final Rule Action: The FAA agrees that curfews on
the west end of GCNP might create a situation whereby large numbers of
aircraft attempt to enter the air tour routes at the same time and
along the same routes. Based on the FAA's safety analysis of the air
tour flights originating from the Las Vegas area, the FAA has decided
to exempt the routes beginning on the western end of the park from any
curfew. This should eliminate any impacts on Native American tribes.
However, Sec. 93.316(a) of the final rule prescribes a fixed
curfew. Specifically, no person shall conduct commercial sightseeing
operations within the Dragon and Zuni Corridors during the following
periods. (1) Summer season (May 1-September 30)--6 p.m. to 8 a.m.
daily; and (2) Winter season (October 1-April 30)--5 p.m. to 9 a.m.
daily.
The FAA has determined that the curfew will increase natural quiet
during sunset and sunrise in the most heavily visited portions of GCNP,
in the eastern portion of the park. The NPS identified these areas as
among the most sensitive parts of the park and these times as when
visitors are especially sensitive to noise impacts. Consequently, the
fixed curfew makes an important contribution to substantially restoring
natural quiet on a daily basis and mitigating noise impacts on the
experience of the park visitors in this portion of the Canyon.
This section of the final rule also responds to the President's
Memorandum of April 22, 1996, charging the Secretary of Transportation
to issue regulations for GCNP that immediately reduce noise and make
further substantial progress toward the restoration of natural quiet,
as defined by the Secretary of the Interior.
The FAA does not agree that the imposition of a curfew will unduly
impact air traffic operations at Grand Canyon National Park Airport.
The FAA believes that there are sufficient air traffic control (ATC)
procedures to manage those aircraft operating to and from the Grand
Canyon National Park Airport, as well as those aircraft transiting the
Class D airspace area. These aircraft will continue to receive ATC
service on a first-come-first-served basis and, if needed, traffic
management procedures will be developed and instituted.

Cap on Commercial Sightseeing Operations

Proposed Cap

Proposed Sec. 93.316(b) set forth a temporary moratorium on
increased commercial sightseeing flights. The proposal limited each
operator in 1997 and 1998 to the number of monthly operations equal to
the monthly operations in the base year August 1, 1995, through July
31, 1996.

Comments on the Proposed Cap

GCATA states that basing the number of monthly operations on the
period August 1, 1995, through July 31, 1996 may not work since some
operators may have encountered a down year; rather an average of the
last three years should be used.
Papillon, Twin Otter, and Grand Canyon Airlines state that capping
flights regardless of type of aircraft would not provide an incentive
to convert to quiet technology, and that caps should only apply to
aircraft of conventional sound signature.
The NTSB says that the proposed caps are discussed almost
exclusively from the perspective of aircraft noise. The NTSB says that
the FAA must also analyze the possible safety impacts of the caps.
GCATC responds to the FAA's suggestions on measures to offset
revenue losses from caps, i.e., using larger aircraft; raising
commercial sightseeing tour prices; rescheduling flights; and diverting
some aircraft to other revenue producing uses. GCATC says that the
operations cap will provide no incentive for operators to invest in
larger aircraft because it will prevent operators from recouping their
investment in an economically feasible time period; operators are
constrained in their ability to raise prices because the demand for
GCNP air tour operators is relatively elastic; rescheduling flights

[[Page 69317]]

has no effect on increasing revenue when the number of flights an
operator may fly is limited artificially by regulation; and air tour
operators would already be using their aircraft for other purposes if
it were economically worthwhile to do so.
A number of commenters (e.g., NPCA, Sierra Club-Grand Canyon
Chapter, Wilderness Society, Grand Canyon Trust) say that basing the
caps on the number of flights in 1995-96 will not restore the natural
quiet and that the caps are too temporary. These commenters recommend
that, since Congress identified the overflight problem in 1987, and the
flight rate since then has dramatically increased, the FAA should use
the 1987 operation levels to determine the caps. In addition, the
maximum caps should be permanent. The Sierra Club-Grand Canyon Chapter
and NPCA also recommend that the flight caps be in effect until
completion and implementation of the comprehensive noise management
plan.
Comments from the Grand Canyon Trust state the FAA's assumptions
that any type of cap, whether it is on operators, aircraft, passengers,
or air tours, will have identical effect is erroneous. Air tour
operators can be expected to adjust their pricing structures, aircraft
fleets, and tour offerings to maximize net operating revenues under
whichever system of caps is adopted. Consequently, the commenter
suggests that the actual economic cost of caps to the industry is
likely to be small.
Grand Canyon River Guides says that since tour operators were
mandated to report and pay for their use of airspace during the base
year, those figures should be used by the NPS and the FAA to determine
the allocation levels; operators who may have been avoiding user fees
by underreporting their operations should not receive any special
consideration. This commenter recommends that, once operational
limitations are in place, the FAA should require that any new aircraft
be quieter than those being replaced, and that, as this shift occurs,
the number of aircraft should not be allowed to increase.
Kenai Helicopters proposes that any cap on air tour operators
should grandfather the current operators, of whom many have made
sizable investments in aircraft and facilities to meet the market
demand. Many of these facilities are located on lands with long term
(20-25 years) leases that necessitate long term operation potential to
stay in business.
Heli USA states that since a large majority of the air carriers
operating tours in GCNP are either new or have not reached the capacity
of business to pay for their investment, caps based on historical
records would be unfair.
Twin Otter and Grand Canyon Airlines state that setting operations
caps raises serious administrative problems. For example, Twin Otter
says that the ``use or lose'' rules which apply to air carrier slots
would not work at the Grand Canyon since air tour schedules are
seasonal and subject to revisions and cancellations for weather. This
commenter says that the only fair alternative would be a slot market
mechanism like that used to allocate restricted capacity at the High
Density Rule airports.
FAA Response and Final Rule Action: In the final rule
Sec. 93.316(b) establishes a cap on commercial sightseeing aircraft
that can operate in the SFRA. Specifically, this section states that no
person may operate more commercial sightseeing aircraft in the Special
Flight Rules Area than the highest number of aircraft that appeared on
the certificate holder's operations specifications, and that were used
for commercial sightseeing operations in the Grand Canyon Special
Flight Rules Area, between July 31, 1996 and December 31, 1996.
NPS modeling suggested that between 1988 and 1994, that part of the
park experiencing a substantial restoration of natural quiet declined
from 43 to 31 percent. The modeling further suggested that by 2010 this
area would decline to about only 10 percent of the park. Because the
FAA and NPS concur that the best way to address the current erosion of
natural quiet and achieve the substantial restoration of natural quiet
is through reducing noise at the source (i.e. quieter aircraft), a cap
is an interim measure needed to prevent a worsening of the situation
prior to implementation of the noise limitations proposed in the NPRM
published simultaneously with this final rule. The combination of the
final rule and the noise limitations in the NPRM will make possible the
substantial restoration of natural quiet mandated by Public Law 100-91.
This section of the final rule also responds to the President's
Memorandum of April 22, 1996, charging the Secretary of Transportation
to issue regulations for GCNP that place appropriate limits on
sightseeing aircraft over GCNP to reduce the noise immediately and make
further substantial progress toward restoration of natural quiet, as
defined by the Secretary of Interior.

Section 93.317 Commercial Sightseeing Flight Reporting Requirements

Proposed Sec. 93.317 established commercial sightseeing flight
reporting requirements. As proposed, during the 5-year period following
May 1, 1997, each certificate holder would submit, in a form and manner
acceptable to the Administrator, three operational reports yearly to
the Las Vegas FSDO. Each report would cover a 4-month period ending
April 30, August 31, or December 31, and would be required to be
submitted no later than 30 days after the reporting period closes.
Certificate holders would be required to provide the aircraft
identification number (registration number), departure airport,
departure date and time, and route(s) for each operation flown in the
SFRA.

Comments on Commercial Sightseeing Flight Reporting Requirements

Two operators state that the reporting requirements would be
oppressive and burdensome, and the costs associated with this
requirement would be passed on to air tour customers. One of these
commenters recommends that if a report is necessary, it should only
require date, departure point, and total number of operations by route.
Grand Canyon River Guides says that, compared with the paperwork
already necessary to keep pilots and aircraft current, the additional
burden of recordkeeping in Notice 96-11 is minor, particularly since
operators probably already are keeping track of such things.
FAA Response and Final Rule Action: Commercial tour operators were
required by SFAR 50-1 to obtain a Part 135 air carrier operating
certificate. The existing reporting requirements under Part 135 for
operators using multiengine aircraft would capture the information
required by this rule. The FAA believes that any recordkeeping burden
imposed by this rule will be minor and related to copying the
information into an FAA format. The required information is needed to
provide accurate information on GCNP overflights for noise and safety
management purposes, to help validate noise models, to determine where
noise mitigation is needed, and to provide the basis for more flexible
noise management system. The recordkeeping requirements in the final
rule therefore are as proposed.

Environmental Review

The FAA conducted an abbreviated scoping process and prepared a
Draft Environmental Assessment (EA) for the proposed rule to assure
conformance with the National Environmental Policy

[[Page 69318]]

Act of 1969 and all applicable environmental laws. Copies of the Draft
EA were circulated to interested parties and placed in the Docket,
where it was available for review. The Notice of Availability of the
Draft EA was issued on August 21, 1996. The original 45-day comment
period, which was scheduled to close on October 4, was extended until
November 18, 1996. Based upon the Draft EA and careful review of the
public comments, the FAA has determined that a finding of no
significant impact (FONSI) is warranted. The final EA and the FONSI
were issued on December 24, 1996. Copies have been placed in the public
docket for this rulemaking, have been circulated to interested parties,
and may be inspected at the same time and location as the final rule.
This final rule constitutes final agency action under 49 U.S.C.
46110. Any party to this proceeding, having a substantial interest may
appeal the order to the courts of appeals of the United States or the
United States Court of Appeals for the District of Columbia upon
petition, filed within 60 days after entry of this Order.

Regulatory Evaluation Summary

Any changes to Federal regulations must undergo several economic
analyses. First, Executive Order 12866 directs that each Federal agency
shall propose or adopt a regulation only upon a reasoned determination
that the benefits of the intended regulation justify its costs. Second,
the Regulatory Flexibility Act of 1980 requires agencies to analyze the
economic effect of regulatory changes on small entities. Third, the
Office of Management and Budget directs agencies to assess the effect
of regulatory changes on international trade. A regulatory evaluation
of the proposal is in the docket.
In conducting these analyses, the FAA has determined that this
Final Rule will be ``a significant regulatory action'' as defined in
the Executive Order and the Department of Transportation Regulatory
Policies and Procedures. However, this rule will not have a significant
impact on a substantial number of small entities.
The final rulemaking will not have a significant impact on
international trade. There may be some increase in the U.S. balance-of-
payments account as a result of a decrease in foreign expenditures on
GCNP tours.

Introduction

To assist the NPS effort to measure aircraft noise levels in GCNP,
the Las Vegas Flight Standards District Office (FSDO) conducted a field
survey of all operators certificated to provide commercial sightseeing
air tours within the GCNP SFRA. The Las Vegas FSDO SFAR No. 50-2 Air
Tour Route Usage Report (field survey) detailed information for each
operator with regard to the number of operations conducted along each
commercial sightseeing air tour route within the GCNP SFRA. This
information was further broken down for each type of commercial air
tour sightseeing aircraft in the operator's fleet that operated along
these routes during the most recent 3 years through early October,
1995. With the exception of the ``Blue Direct South'' and certain
``Brown'' routes for fixed wing aircraft and the ``Green 3'' and
``Green 3A'' routes for helicopters, all routes identified in the Grand
Canyon VFR Aeronautical Chart were identified by GCNP commercial air
tour sight

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A96-33146. Public record. Not legal advice.