Use of 112-118 MHz for Differential Global Positioning System (GPS) Correction Data and the Use of Hand-Held Transmitters on Frequencies in the Aeronautical Enroute Service

FEDERAL COMMUNICATIONS COMMISSION

47 CFR Parts 17 and 87

[WT Docket No. 96-211, FCC 99-40]

Use of 112-118 MHz for Differential Global Positioning System

(GPS) Correction Data and the Use of Hand-Held Transmitters on

Frequencies in the Aeronautical Enroute Service

AGENCY: Federal Communications Commission.

ACTION: Final rule.

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SUMMARY: This Report and Order (R&O) amends the Commission's rules

regarding the use of 112-118 MHz for differential Global Positioning

System (GPS) correction data, the use of hand-held transmitters on

frequencies in the Aeronautical Enroute Service, and to update Part 17

of our rules to incorporate by reference two recently revised FAA

Advisory Circulars. These amendments were adopted in response to

petitions for rule making filed by the Federal Aviation Administration

and the Aeronautical Radio, Inc. The effect of these amendments would

increase aircraft and airport safety and facilitate the efficient use

of aeronautical radio spectrum.

DATES: These regulations are effective May 20, 1999. The incorporation

by reference of certain publications listed in the regulations is

approved by the Director of Federal Register May 20, 1999.

FOR FURTHER INFORMATION CONTACT: James Shaffer of the Commission's

Wireless Telecommunications Bureau at (202) 418-0680 or via email at

[email protected].

SUPPLEMENTARY INFORMATION: This is a summary of the Commission's R&O,

FCC 99-40, adopted February 25, 1999, and released March 3, 1999. The

full text of this Report and Order is available for inspection and

copying during normal business hours in the FCC Reference Center, Room

246, 1919 M Street N.W. Washington, D.C. The complete text may be

purchased from the Commission's copy contractor, ITS, Inc., 1231 20th

St. N.W., Washington, D.C. 20036, telephone (202) 857-3800.

Summary of R&O

1. This R&O amends Part 87 of our rules to permit aeronautical

ground stations to use frequencies in the 112-118 MHz band to transmit

differential Global Positioning System (GPS) information to aircraft

equipped to use advanced landing systems in response to a petition for

rule making filed by the Federal Aviation Administration (FAA). This

R&O also allows the use of hand-held radios for direct communications

between ground service personnel and flight crews on frequencies

allocated to the Aeronautical Enroute Service in response to a petition

for rule making filed by Aeronautical Radio, Inc. (ARINC). Finally,

this R&O updates part 17 of our rules to incorporate by reference two

recently revised FAA Advisory Circulars. The actions will increase the

safety and efficiency of aircraft navigation and movement of aircraft

in and around airports. Further, these amends should promote the use of

new radio technologies beneficial to aircraft without allocating

additional spectrum.

Administrative Matters

Final Regulatory Flexibility Analysis

2. As required by the Regulatory Flexibility Act, 5 U.S.C. 603

(RFA), Initial Regulatory Flexibility Analyses (IRFA) were incorporated

in the Notice of Proposed Rule Makings WT Docket 96-1 and WT Docket 96-

211.1 The Commission sought written public comments on the

proposals in the Unicom NPRM and Aviation Safety NPRM, including on the

IRFA. The Commission's Final Regulatory Flexibility Analysis (FRFA) in

this Report and Order conforms to the RFA, as amended by the Contract

With America Advancement Act of 1996.2

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\1\ Amendment of Part 87 of the Commission's Rules to Permit

Automatic Operation of Aeronautical Advisory Stations (Unicoms), WT

Docket 96-1, Notice of Proposed Rule Making, 11 FCC Rcd 1084 (1996),

61 FR 8905, (March 6, 1996), (Unicom NPRM); Amendment of part 87 to

Permit the Use of 112-118 MHz for Differential Global Positioning

System (GPS) Correction Data and the Use of Hand-held Transmitters

on Frequencies in the Aeronautical Enroute Service and Amendment of

Part 17 Concerning Construction, Marking, and Lighting of Antenna

Structures, WT Docket No. 96-211, Notice of Proposed Rule Making, 11

FCC Rcd 15391 (1996), 61 FR 60673, (November 29, 1996), (Aviation

Safety NPRM).

\2\ Public Law No. 104-121, 110 Stat. 847 (1996) (CWAAA). Title

II of the CWAAA is ``The Small Business Regulatory Enforcement

Fairness Act of 1996'' (SBREFA), codified at 5 U.S.C. 601 et seq.

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I. Need for and Objective of the Proposed Rules

3. Our objective is to improve safety in air navigation by

increasing pilots' access to advisory information, promoting the use of

satellite technology for the precision landing of aircraft and allowing

ground crews to communicate with aircraft on aeronautical enroute

frequencies, and to incorporate by reference two recently revised FAA

Advisory Circulars. The Report and Order in this proceeding modified

the Commission's rules to increase the safety and efficiency of

aircraft navigation and movement of aircraft in and around airports.

4. The public interest is served by modifying our rules to permit

the operation of aeronautical advisory stations (unicoms) in an

unattended, automated mode, allow aeronautical ground stations to

transmit differential GPS augmentation data to aircraft, allow the use

of mobile radios for direct communications between ground service

personnel and flight crews on Aeronautical Enroute Service frequencies

and incorporate, by reference, two FAA Advisory Circulars.

II. Summary of Significant Issues Raised by the Public Comments in

Response to the Initial Regulatory Flexibility Analysis

5. No comments were submitted in direct response to the IRFA. We

have, however, reviewed general comments that may impact small

businesses.

6. Much of the impact will be on small businesses that use,

manufacture, design, import, or sell equipment, and will increase

safety and efficiency at airports by allowing new uses and technologies

for the purpose of communicating important information for flight and

ground safety. Commenters submitted suggestions to improve the

technical and operational criteria of the proposals. This Report and

Order directly benefits small businesses by providing smaller airports

that do not have sufficient resources to staff a unicom station with an

automated and economically viable alternative to provide important

advisory information, providing airports with satellite technology for

the precision landing of aircraft to facilitate approaches and landings

in poor weather conditions, and improving the safe ground operations at

airports and improve the provision of services and supplies to aircraft

on the ground. These actions should increase the safety and efficiency

of aircraft navigation and movement of aircraft in and around airports.

III. Description and Estimate of the Number of Small Entities to

Which the Rules Apply

7. The rules adopted in this Report and Order will affect small

businesses that use, manufacture, design, import, sell, or use aviation

equipment designed for an automated unicom, a GPS augmentation system

operating in the 112-118 MHz band, and mobile radios

[[Page 27473]]

used for direct communications between ground service personnel and

flight crews on Aeronautical Enroute Service frequencies. There are no

Commission-imposed requirements, however, for any entity to use these

products.

Estimates for Unicoms

8. The unicom service provides for air-ground communications

primarily between general aviation aircraft and airport facilities.

Unicom transmissions are limited to the necessities of safe and

expeditious operation of aircraft, including runway conditions, types

of fuel available, wind conditions, weather information, dispatching,

and other necessary safety information. Unicom transmissions may

include, on a secondary basis, communications pertaining to the

efficient portal-to-portal transit of an aircraft, such as available

ground transportation, food, and lodging. Unicoms must provide

impartial information concerning available ground services, and must

provide service to any aircraft station upon request and without

discrimination. For the purpose of determining whether a licensee is a

small business as defined by the Small Business Administration (SBA),

each licensee would need to be evaluated within its own business area.

9. Because the Regulatory Flexibility Act amendments were not in

effect until the record in this proceeding was closed, the Commission

was unable to request information regarding the number of small

entities that are unicoms. Therefore, the Commission is unable at this

time to determine the number of small businesses which could be

impacted by the rules. However, the Commission's data indicates that

there were 2775 unicoms licensees operating at the end of October 1996.

Further, because any entity engaged in providing unicom service is

eligible to hold a unicom license, these rules could potentially impact

every small business involved in aviation. Additionally, there are

small businesses that will manufacture, design, import, or sell

equipment. We concluded that these small businesses are classified in

Communications Equipment, N.E.C., (Standard Identification Code 3669)

as entities employing less than 750 employees as defined in 13 CFR

121.201. The size data provided by the SBA shows that 469 firms out of

498 firms in the Communications Equipment, N.E.C. classification have

less than 750 employees but did not enable us to make a meaningful

estimate of the number of potential manufacturers which are small

businesses.3

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\3\ U.S. Small Business Administration 1992 Economic Census

Industry and Enterprise Report, Table 1D, SIC Code 3669, (Bureau of

the Census data adapted by the Office of Advocacy of the U.S. Small

Business Administration).

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Estimates for Differential GPS

10. Differential GPS is ground reference stations licensed to

private entities using unassigned VOR frequencies in the 112-118 MHz

band to transmit differential GPS augmentation data to aircraft to

improve safety in approach and landing of aircraft. For the purpose of

determining whether a licensee is a small business as defined by the

Small Business Administration (SBA), each licensee would need to be

evaluated within its own business area. Additionally, there are small

businesses that will manufacture, design, import, or sell equipment. We

concluded that these small businesses are classified in Communications

Equipment, N.E.C., (Standard Identification Code 3669) as entities

employing less than 750 employees as defined in 13 CFR 121.201. We

invited comment on whether this is the correct definition to use, but

received no comment on this issue. The size data provided by the SBA

shows that 469 firms out of 498 firms in the Communications Equipment,

N.E.C. classification have less than 750 employees but did not enable

us to make a meaningful estimate of the number of potential GPS

manufacturers which are small businesses.4 However, based on

information from the U.S. GPS Industry Council we estimate that this

would include approximately 110 small businesses that would be affected

by this proposed rule change.

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\4\ U.S. Small Business Administration 1992 Economic Census

Industry and Enterprise Report, Table 1D, SIC Code 3669, (Bureau of

the Census data adapted by the Office of Advocacy of the U.S. Small

Business Administration).

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IV. Description of Projected Reporting, Recordkeeping, and Other

Compliance Requirements of the Rules

11. There are several reporting, recordkeeping, and compliance

requirements applicable to the Commission licensees and equipment

manufacturers. These new requirements are necessary to minimize

radiofrequency interference of the equipment, and to specify the

responsibilities in operating unicom.

(1) In order to facilitate operation of aviation equipment, these

rules may have significant economic impact on a substantial number of

small businesses. Prior to marketing aviation equipment in the U.S., a

manufacturer must have the unit type accepted by the Commission under

the technical criteria set forth in the Commission's Rules. In order to

have a unit type accepted, a small entity would have to test the radio

equipment and provide clerical support to file the requisite FCC

application forms. Both of these functions could be handled by a third

party. We estimate that the initial cost to the manufacturer to meet

this requirement, if done by a third party, is $900 to test the

equipment and complete the filing information, and would require the

electronic engineering professional skills. Additionally, there would

be a $425 equipment authorization fee to file the application for type

acceptance. These costs are one time costs to type accept the equipment

and assure that interference to other radio users is minimized.

(2) In order to clarify the responsibilities in operating unicoms,

we require all unicom licensees at airports having more than one unicom

to jointly sign a letter of agreement, prior to the operation of a

unicom in automatic mode at such an airport, stating the name(s) of the

licensee(s) who will control the automatic unicom and, if applicable,

how control of the automatic unicom will be divided. A copy of the

agreement must be kept with each licensee's station authorization. We

estimate that approximately 50 licensees will require 0.7 hours to

prepare and file the agreement required.

V. Steps Taken by Agency To Minimize Significant Economic Impact on

Small Entities Consistent With Stated Objectives

12. The rules would require differential GPS transmitters to be

type accepted in accordance with the technical criteria set forth in

part 87 subpart D of our rules, in lieu of the more exacting

specifications contained in RTCA Document No. DO-217. This flexible

approach promotes technological innovations in differential GPS

equipment so long as such equipment is compatible with the National

Airspace System. Under our present treatment of transmitters operating

in the 108-137 MHz band, the FAA is given a 21-day period to object to

any application for type acceptance that would adversely affect the

performance of the National Airspace System. The rules also take

measures to expedite coordination procedures between applicants, the

FAA, and the Commission concerning the assignment of a frequency and

time slot for differential GPS ground stations. In order to reduce

administrative burdens on both the public and the Commission,

[[Page 27474]]

we permit mobile units in the aeronautical enroute service to operate

under the same authorization and call sign as the associated

aeronautical enroute station. This approach would eliminate the need

for aviation service organizations to submit forms and fees to the

Commission. These decisions benefit small entities and give them an

opportunity to provide recommendations to further improve the impact

and processes.

VI. Report to Congress

13. The Commission shall send a copy of this Final Regulatory

Flexibility Analysis, along with the Report and Order, in a report to

Congress pursuant to the SBREFA.5 A copy of this FRFA will

also be published in the Federal Register.

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\5\ See 5. U.S.C. 801(a)(1)(A).

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Ordering Clauses

14. Accordingly, it is ordered that, pursuant to the authority of

Sections 4(i), 303(r), 307(e), and 332(a)(2) of the Communications Act

of 1934, as amended, 47 U.S.C. 154(i), 303(r), 307(e) and 332(a)(2),

parts 80 and 87 of the Commission's Rules, 47 CFR Parts 17 and 87 are

amended as set forth in the Rule Changes, effective May 20, 1999.

15. It is further ordered that these proceedings are terminated.

List of Subjects

47 CFR Part 17

Antenna, Aviation safety, Communications equipment, Incorporation

by reference, Radio.

47 CFR Part 87

Aviation safety, Communications equipment, Radio.

Federal Communications Commission.

Magalie Roman Salas,

Secretary.

Rule Changes

For the reasons discussed in the preamble, the Federal

Communications Commission amends 47 CFR parts 17 and 87 as follows:

PART 17--CONSTRUCTION, MARKING, AND LIGHTING OF ANTENNA STRUCTURES

1. The authority citation for Part 17 continues to read as follows:

Authority: Secs. 4, 303, 48 Stat. 1066, 1082, as amended; 47

U.S.C. 154, 303. Interpret or apply secs. 301, 309 48 Stat. 1081,

1085 as amended, 47 U.S.C. 301, 309.

2. Section 17.23 is revised to read as follows:

Sec. 17.23 Specifications for painting and lighting antenna

structures.

Unless otherwise specified by the Commission, each new or altered

antenna structure to be registered on or after January 1, 1996, must

conform to the FAA's painting and lighting recommendations set forth on

the structure's FAA determination of ``no hazard,'' as referenced in

the following FAA Advisory Circulars: AC 70/7460-1J, ``Obstruction

Marking and Lighting,'' effective January 1, 1996, and AC 150/5345-43E,

``Specification for Obstruction Lighting Equipment,'' dated October 19,

1995. These documents are incorporated by reference in accordance with

5 U.S.C. 552(a). The documents contain FAA recommendations for painting

and lighting structures which pose a potential hazard to air

navigation. For purposes of this part, the specifications, standards,

and general requirements stated in these documents are mandatory. The

Advisory Circulars listed are available for inspection at the

Commission Headquarters in Washington, DC, or may be obtained from

Department of Transportation, Property Use and Storage Section,

Subsequent Distribution Office, M483.6, Ardmore East Business Center,

3341 Q 75th Avenue, Landover, MD 20785, telephone (301) 322-4961,

facsimile (301) 386-5394. Copies are also available for public

inspection at the Office of the Federal Register, 800 North Capitol

Street, Suite 700, Washington, D.C.

PART 87--AVIATION SERVICES

3. The authority citation for Part 87 continues to read as follows:

Authority: 48 Stat. 1066, 1082, as amended; 47 U.S.C. 154, 303,

307(e) unless otherwise noted. Interpret or apply 48 Stat. 1064-

1068, 1081-1105, as amended, 47 U.S.C. 151-156, 301-609.

4. Section 87.5 is amended by revising the definition of

``automatic weather observation station'' to read as follows:

Sec. 87.5 Definitions.

* * * * *

Automatic weather observation station (AWOS) or automatic surface

observation station (ASOS). A land station located at an airport and

used to automatically transmit weather information to aircraft.

* * * * *

5. Section 87.131 is amended by adding a footnote to Aeronautical

advisory entry and adding to the end of the table, an entry for

Differential GPS to read as follows:

Sec. 87.131 Power and emissions.

* * * * *

----------------------------------------------------------------------------------------------------------------

Authorized emission(s)

Class of station Frequency band/frequency \9\ Maximum power \1\

----------------------------------------------------------------------------------------------------------------

Aeronautical advisory.............. VHF........................ A3E 10 watts.\10\

* * * * * *

*

Differential GPS................... VHF........................ G7D Various.\2\

----------------------------------------------------------------------------------------------------------------

\1\ The power is measured at the transmitter output terminals and the type of power is determined according to

the emission designator as follows:

(i) Mean power (pY) for amplitude modulated emissions and transmitting both sidebands using unmodulated full

carrier.

(ii) Peak envelope power (pX) for all emission designators other than those referred to in paragraph (i) of

this note.

\2\ Power and antenna height are restricted to the minimum necessary to achieve the required service.

* * * * * *

*

\9\ Excludes automatic link establishment.

\10\ Power is limited to 0.5 watt, but may not exceed 2 watts when station is used in an automatic unattended

mode.

6. Section 87.133 is amended by adding to the table in paragraph

(a) in the (5) Band-100 to 137 MHz: entry, an entry for Differential

GPS to read as follows:

Sec. 87.133 Frequency stability.

(a) * * *

[[Page 27475]]

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Frequency band (lower limit exclusive,

upper limit inclusive), and categories Tolerance \1\ Tolerance \2\

of stations

------------------------------------------------------------------------

* * * * * *

*

(5) Band-100 to 137 MHz:

* * * * * *

*

Differential GPS.................... .............. 2

* * * * * *

*

------------------------------------------------------------------------

\1\ This tolerance is the maximum permitted until January 1, 1990, for

transmitters installed before January 2, 1985, and used at the same

installation. Tolerance is indicated in parts in 10\6\ unless shown as

Hertz (Hz).

\2\ This tolerance is the maximum permitted after January 1, 1985 for

new and replacement transmitters and to all transmitters after January

1, 1990. Tolerance is indicated in parts in 10\6\ unless shown as

Hertz (Hz).

* * * * *

7. Section 87.137 is amended by adding to the table in paragraph

(a) in its alphabetical order, an entry for G7D to read as follows:

Sec. 87.137 Types of emission.

(a) * * *

----------------------------------------------------------------------------------------------------------------

Authorized bandwidth (kilohertz)

-----------------------------------------------

Class of emission Emission designator Frequency

Below 50 MHz Above 50 MHz deviation

----------------------------------------------------------------------------------------------------------------

* * * * * * *

G7D................................ 14K0G7D.................... .............. 25

* * * * * * *

----------------------------------------------------------------------------------------------------------------

8. Section 87.139 is amended by revising the introductory text in

paragraph (a), and paragraph (j) to read as follows:

Sec. 87.139 Emission limitations.

(a) Except for ELTs and when using single sideband (R3E, H3E, J3E),

or frequency modulation (F9) or digital modulation (F9Y) for telemetry

or telecommand in the frequency bands 1435-1535 MHz and 2310-2390 MHz

or digital modulation (G7D) for differential GPS, the mean power of any

emission must be attenuated below the mean power of the transmitter

(pY) as follows:

* * * * *

(j) When using G7D for differential GPS in the 112-118 MHz band,

the amount of power during transmission under all operating conditions

when measured over a 25 kHz bandwidth centered on either of the second

adjacent channels shall not exceed -25 dBm and shall decrease 5 dB per

octave until -52 dBm.

9. Section 87.171 is amended by adding in its alphabetical order

the symbol and class of station for DGP to read as follows:

Sec. 87.171 Class of station symbols.

* * * * *

DGP--Differential GPS.

* * * * *

10. Section 87.173 is amended by adding in numeric order the

listing 112-118 MHz to read as follows:

Sec. 87.173 Frequencies.

* * * * *

(b) * * *

----------------------------------------------------------------------------------------------------------------

Frequency or frequency band Subpart Class of station Remarks

----------------------------------------------------------------------------------------------------------------

* * * * * *

*

112-118 MHz......................... Q DGP Differential GPS.

* * * * * *

*

----------------------------------------------------------------------------------------------------------------

11. Section 87.187 is amended by revising paragraph (y)

introductory text and the introductory text of paragraph (y)(4) to read

as follows:

Sec. 87.187 Frequencies.

* * * * *

(y) Brief keyed RF signals (keying the transmitter by momentarily

depressing the microphone ``push-to-talk'' button) may be transmitted

from aircraft for the control of automated unicoms on the unicom

frequencies listed in paragraph (y)(3) of this section, or for the

control of airport lights on the following frequencies:

* * * * *

(4) Aviation support station frequencies listed in Sec. 87.323(b):

* * *

* * * * *

12. A new Sec. 87.219 is added to Subpart G to read as follows:

Sec. 87.219 Automatic operations.

(a) A station operator need not be present when an automated unicom

is in operation.

(b) Unicoms operating in an automated mode must comply with the

requirements of paragraphs (1)-(5) of this section, in addition to the

requirements applicable to non-automated unicom operations.

(1) An automated unicom must transmit only in response to

interrogating signals from aircraft,

[[Page 27476]]

including but not limited to the brief keyed RF signals specified in

Sec. 87.187(y).

(2) An automated unicom must monitor the unicom frequency prior to

transmission, and provide a brief delay between the aircraft's

interrogating signal and the automatic unicom's response.

(3) Automated advisory transmissions must be as brief as possible,

and must never exceed one minute in length.

(4) An automated unicom may not provide weather information at an

airport that has an operational, FAA-certified, automatic weather

facility, unless the unicom itself is certified by the FAA.

(5) If weather information is provided by an automated unicom:

(i) weather sensors must be placed in order to adequately represent

the weather conditions at the airport(s) to be served;

(ii) the weather information must be proceeded by the word

``advisory;''

(iii) the phrase ``automated advisory'' must be included when the

weather information was gathered by real-time sensors or within the

last minute; and,

(iv) the time and date of the last update must be included when the

weather information was not gathered within the last minute.

(c) Only one automated unicom may be operated at an uncontrolled

airport. Prior to the operation of an automated unicom at an airport

with more than one unicom licensee, all of the licensees at that

airport must sign a letter of agreement stating which licensee(s)

control the automated unicom operations, and, if control is to be

shared among several operators, how that control will be divided or

scheduled. The original or a copy of the letter of agreement must be

kept with each licensees' station records. Within 90 days of the date

upon which a new unicom operator is licensed at an airport where more

than one unicom is authorized, and an automated unicom is being

operated, an amended letter of agreement that includes the new

licensee's signature must be signed or automated unicom operations must

cease.

13. Section 87.261 is amended by adding paragraphs (e) and (f) to

read as follows:

Sec. 87.261 Scope of service.

* * * * *

(e) Mobile units may be operated under an aeronautical enroute

station authorization so long as the units are limited to use at an

airport and are only used to communicate with aircraft on the ground or

the associated aeronautical enroute station. Mobile units are further

limited to operation on the VHF frequencies listed in 87.263(a)(1).

(f) Mobile units licensed under paragraph (e) of this section shall

not be operated on air traffic control frequencies, nor cause harmful

interference to, communications on air traffic control frequencies.

14. Section 87.419 is revised to read as follows:

Sec. 87.419 Supplemental eligibility.

Only one control tower or RCO will be licensed at an airport.

15. Section 87.475 is amended by adding paragraph (e) to read as

follows:

Sec. 87.475 Frequencies.

* * * * *

(e) Frequencies available for differential GPS stations.

Frequencies in the 112-118 MHz band may be assigned to Special Category

I (SCAT-I) ground stations for differential GPS data links.

(1) The frequencies available are on 25 kHz centers with the lowest

assignable frequency being centered at 112.000 MHz and the highest

assignable frequency being centered at 117.950 MHz.

(2) Applicants must coordinate a frequency, time slot assignment,

and three-letter identifier with the FAA and provide this information

to the Commission upon application.

16. Subpart S is amended by revising the heading to read as

follows:

Subpart S--Automatic Weather Stations (AWOS/ASOS)

17. Section 87.525 is revised to read as follows:

Sec. 87.525 Scope of service.

Automatic weather observation stations (AWOS) and automatic surface

observation stations (ASOS) must provide up-to-date weather information

including the time of the latest weather sequence, altimeter setting,

wind speed and direction, dew point, temperature, visibility and other

pertinent data needed at airports having neither a full-time control

tower nor a full-time FAA Flight Service Station. When a licensee has

entered into an agreement with the FAA, an AWOS or an ASOS may also

operate as an automatic terminal information station (ATIS) during the

control tower's operating hours.

18. Section 87.527 is amended by revising paragraphs (b) and (c) to

read as follows:

Sec. 87.527 Supplemental eligibility.

* * * * *

(b) Eligibility for an AWOS, an ASOS, or an ATIS is limited to the

owner or operator of an airport or to a person who has entered into a

written agreement with the owner or operator for exclusive rights to

operate and maintain the station. Where applicable a copy of the

agreement between the applicant and owner or operator of the airport

must be submitted with an application.

(c) Only one AWOS, ASOS, or ATIS will be licensed at an airport.

19. Section 87.529 is amended by revising the fourth and fifth

sentences to read as follows:

Sec. 87.529 Frequencies.

* * * Normally, frequencies available for air traffic control

operations set forth in subpart E will be assigned to an AWOS, ASOS, or

to an ATIS. When a licensee has entered into an agreement with the FAA

to operate the same station as both an AWOS and as an ATIS, or as an

ASOS and an ATIS, the same frequency will be used in both modes of

operation.

[FR Doc. 99-12173 Filed 5-19-99; 8:45 am]

BILLING CODE 6712-01-P