Airworthiness Directives; Fokker Model F28 Mark 0070 and Mark 0100 Series Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-248-AD; Amendment 39-10709; AD 98-17-07]

RIN 2120-AA64

Airworthiness Directives; Fokker Model F28 Mark 0070 and Mark

0100 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD),

applicable to all Fokker Model F28 Mark 0070 and Mark 0100 series

airplanes, that requires inspection of the wing leading edge sections

for the correct amount of bleed air exhaust holes, and corrective

actions, if necessary. This amendment is prompted by issuance of

mandatory continuing airworthiness information by a foreign civil

airworthiness authority. The actions specified by this AD are intended

to prevent malfunction of the wing leading edge thermal anti-ice

system, which could result in reduced controllability of the airplane

and/or reduced structural integrity of the wing due to overheating.

DATES: Effective September 18, 1998.

The incorporation by reference of certain publications listed in

the regulations is approved by the Director of the Federal Register as

of September 18, 1998.

ADDRESSES: The service information referenced in this AD may be

obtained from Fokker Services B.V., Technical Support Department, P. O.

Box 75047, 1117 ZN Schiphol Airport, the Netherlands. This information

may be examined at the Federal Aviation Administration (FAA), Transport

Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton,

Washington; or at the Office of the Federal Register, 800 North Capitol

Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager,

International Branch, ANM-116, FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)

227-2110; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39) to include an airworthiness

directive (AD) that is applicable to all Fokker Model F28 Mark 0070 and

Mark 0100 series airplanes was published in the Federal Register on

December 9, 1997 (62 FR 64775). That action proposed to require

inspection of the wing leading edge sections for the correct amount of

bleed air exhaust holes, and corrective actions, if necessary.

Comments

Interested persons have been afforded an opportunity to participate

in the making of this amendment. Due consideration has been given to

the comments received.

One commenter supports the proposed rule.

Request To Revise Compliance Time for Follow-On Actions

One commenter supports the requirement for conducting the initial

inspection within 60 days, as specified in the proposed AD, but

strongly opposes the requirement to further inspect and accomplish

leading edge repairs prior to further flight. The commenter notes that

Fokker Service Bulletin SBF100-57-032, dated August 21, 1995, was

issued over two years ago, and provides a recommended compliance time

for accomplishment of these follow-on actions. The commenter states

that, since the time to detect the discrepancy is extended an

additional 60 days by the proposed AD, it is very improbable that any

degradation that may be found will warrant permanent repair prior to

further flight. The commenter suggests that, based on the severity of

the damage that could be expected, a time scale should be developed

correlating the time allowed to accomplish the additional inspections

and repair work with the number of holes found missing. The commenter

requests that the proposed AD be revised to allow 1,200 flight hours,

as a minimum, for accomplishment of the follow-on actions; such a

revision would enable the work to be accomplished during a scheduled

maintenance period.

The FAA does not concur with the commenter's request. The FAA has

determined that, should any missing holes or heat damage be detected

during the initial inspection required by this AD, an unsafe condition

exists that necessitates repairs prior to further flight in order to

adequately address that condition. As a matter of law, in order to be

airworthy, an airplane must conform to its type design and be in a

condition for safe operation. Apart from the requirements of this AD,

if such missing holes or heat damage of the wing leading edge were

found on an airplane at any time, the airplane would be rendered

unairworthy and, as such,

[[Page 43613]]

would require repair prior to further flight.

Further, the commenter has not provided any data to substantiate

why continued flight should be allowed with missing bleed air holes in

the wing leading edge section, or with heat damage to this area.

However, under the provisions of paragraph (c) of the final rule, an

operator may request an adjustment to the compliance time, if

sufficient data are submitted to justify why such an extension would

not compromise safety.

Conclusion

After careful review of the available data, including the comments

noted above, the FAA has determined that air safety and the public

interest require the adoption of the rule as proposed.

Cost Impact

The FAA estimates that 131 Fokker Model F28 Mark 0070 and 0100

series airplanes of U.S. registry will be affected by this AD, that it

will take approximately 1 work hour per airplane to accomplish the

required inspection, and that the average labor rate is $60 per work

hour. Based on these figures, the cost impact of the required

inspection on U.S. operators is estimated to be $7,860, or $60 per

airplane.

The cost impact figure discussed above is based on assumptions that

no operator has yet accomplished any of the requirements of this AD

action, and that no operator would accomplish those actions in the

future if this AD were not adopted.

Regulatory Impact

The regulations adopted herein will not have substantial direct

effects on the States, on the relationship between the national

government and the States, or on the distribution of power and

responsibilities among the various levels of government. Therefore, in

accordance with Executive Order 12612, it is determined that this final

rule does not have sufficient federalism implications to warrant the

preparation of a Federalism Assessment.

For the reasons discussed above, I certify that this action (1) is

not a ``significant regulatory action'' under Executive Order 12866;

(2) is not a ``significant rule'' under DOT Regulatory Policies and

Procedures (44 FR 11034, February 26, 1979); and (3) will not have a

significant economic impact, positive or negative, on a substantial

number of small entities under the criteria of the Regulatory

Flexibility Act. A final evaluation has been prepared for this action

and it is contained in the Rules Docket. A copy of it may be obtained

from the Rules Docket at the location provided under the caption

ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by

reference, Safety.

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the

Administrator, the Federal Aviation Administration amends part 39 of

the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding the following new

airworthiness directive:

98-17-07 Fokker: Amendment 39-10709. Docket 97-NM-248-AD.

Applicability: All Model F28 Mark 0070 and Mark 0100 series

airplanes, certificated in any category.

Note 1: This AD applies to each airplane identified in the

preceding applicability provision, regardless of whether it has been

modified, altered, or repaired in the area subject to the

requirements of this AD. For airplanes that have been modified,

altered, or repaired so that the performance of the requirements of

this AD is affected, the owner/operator must request approval for an

alternative method of compliance in accordance with paragraph (c) of

this AD. The request should include an assessment of the effect of

the modification, alteration, or repair on the unsafe condition

addressed by this AD; and, if the unsafe condition has not been

eliminated, the request should include specific proposed actions to

address it.

Compliance: Required as indicated, unless accomplished

previously.

To prevent malfunction of the wing leading edge thermal anti-ice

system, which could result in reduced controllability of the

airplane and/or reduced structural integrity of the wing due to

overheating, accomplish the following:

(a) Within 60 days after the effective date of this AD, inspect

all wing leading edge sections for the presence of the correct

number of bleed air exhaust holes, in accordance with Part 1 of the

Accomplishment Instructions of Fokker Service Bulletin SBF100-57-

032, dated August 21, 1995. If any missing holes are detected, prior

to further flight, accomplish paragraphs (a)(1) and (a)(2) of this

AD, in accordance with Part 2 of the Accomplishment Instructions of

the service bulletin:

(1) Rework the affected wing leading edge section(s) to add the

correct number of holes, and

(2) Perform a visual inspection of the auxiliary spar or front

spar, as applicable, to detect heat damage. If any heat damage is

detected, prior to further flight, repair the affected structure in

accordance with a method approved by the Manager, International

Branch, ANM-116, FAA, Transport Airplane Directorate.

(b) As of the effective date of this AD, no person shall install

on any airplane a wing leading edge section, unless it has been

inspected for the presence of the correct number of bleed air

exhaust holes, and reworked, if necessary, to add the correct number

of holes, in accordance with Fokker Component Service Bulletin

D14000-57-004, dated August 21, 1995.

(c) An alternative method of compliance or adjustment of the

compliance time that provides an acceptable level of safety may be

used if approved by the Manager, International Branch, ANM-116, FAA,

Transport Airplane Directorate. Operators shall submit their

requests through an appropriate FAA Principal Maintenance Inspector,

who may add comments and then send it to the Manager, International

Branch, ANM-116.

Note 2: Information concerning the existence of approved

alternative methods of compliance with this AD, if any, may be

obtained from the International Branch, ANM-116.

(d) Special flight permits may be issued in accordance with

sections 21.197 and 21.199 of the Federal Aviation Regulations (14

CFR 21.197 and 21.199) to operate the airplane to a location where

the requirements of this AD can be accomplished.

(e) The actions shall be done in accordance with Fokker Service

Bulletin SBF100-57-032, dated August 21, 1995; and Fokker Component

Service Bulletin D14000-57-004, dated August 21, 1995. This

incorporation by reference was approved by the Director of the

Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part

51. Copies may be obtained from Fokker Services B.V., Technical

Support Department, P. O. Box 75047, 1117 ZN Schiphol Airport, the

Netherlands. Copies may be inspected at the FAA, Transport Airplane

Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the

Office of the Federal Register, 800 North Capitol Street, NW., suite

700, Washington, DC.

Note 3: The subject of this AD is addressed in Dutch

airworthiness directive BLA No. 1995-087 (A), dated August 31, 1995.

(f) This amendment becomes effective on September 18, 1998.

Issued in Renton, Washington, on August 6, 1998.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 98-21653 Filed 8-13-98; 8:45 am]

BILLING CODE 4910-13-U