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[Federal Register Volume 62, Number 236 (Tuesday, December 9, 1997)]
[Proposed Rules]
[Pages 64775-64777]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-32113]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-248-AD]
RIN 2120-AA64

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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to all Fokker Model F28 Mark 0070 and 
Mark 0100 series airplanes. This proposal would require inspection of 
the wing leading edge sections for the correct amount of bleed air 
exhaust holes, and corrective actions, if necessary. This proposal is 
prompted by issuance of mandatory continuing airworthiness information 
by a foreign civil airworthiness authority. The actions specified by 
the proposed 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: Comments must be received by January 8, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 97-NM-248-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule 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 FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: 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:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications shall identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 97-NM-248-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules 
Docket No. 97-NM-248-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Rijksluchtvaartdienst (RLD), which is the airworthiness 
authority for the Netherlands, notified the FAA that an unsafe 
condition may exist on all Fokker Model F28 Mark 0070 and Mark 0100 
series airplanes. The RLD advises that, during assembly of a Fokker 
Model F28 Mark 0100 series airplane, it was discovered that the number 
of bleed air exhaust holes in one of the wing leading edge sections was 
not in conformity with type design. Subsequent investigation revealed 
that some spare wing leading edge sections did not have any bleed air 
exhaust holes present.

[[Page 64776]]

Missing bleed air exhaust holes may cause improper bleed air 
circulation within the wing thermal anti-ice system. This condition, if 
not corrected, could result in 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.

Explanation of Relevant Service Information

    Fokker has issued Service Bulletin SBF100-57-032, dated August 21, 
1995, which describes procedures for a one-time visual inspection of 
the wing leading edge sections for the correct amount of bleed air 
exhaust holes, and rework of the wing leading edge sections to add the 
correct amount of holes, if necessary. The service bulletin also 
describes procedures for visual inspection of the adjacent structure of 
certain wing leading edge sections to detect heat damage, and repair, 
if necessary. The service bulletin references Fokker Component Service 
Bulletin D14000-57-004, dated August 21, 1995, as an additional sources 
of service information for a one-time visual inspection of the wing 
leading edge sections held in spares for the correct amount of bleed 
air exhaust holes, and rework of the wing leading edge sections to add 
the correct amount of holes, if necessary. Accomplishment of the 
actions specified in the service bulletins is intended to adequately 
address the identified unsafe condition. The RLD classified these 
service bulletins as mandatory and issued Dutch airworthiness directive 
BLA No. 1995-087 (A), dated August 31, 1995, in order to assure the 
continued airworthiness of these airplanes in the Netherlands.

FAA's Conclusions

    These airplane models are manufactured in the Netherlands and are 
type certificated for operation in the United States under the 
provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 
21.29) and the applicable bilateral airworthiness agreement. Pursuant 
to this bilateral airworthiness agreement, the RLD has kept the FAA 
informed of the situation described above. The FAA has examined the 
findings of the RLD, reviewed all available information, and determined 
that AD action is necessary for products of this type design that are 
certificated for operation in the United States.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would require accomplishment of 
the actions specified in the service bulletins described previously, 
except as discussed below.

Differences Between Proposed Rule and Service Bulletin

    Fokker Service Bulletin SBF100-57-032, dated August 21, 1995, 
specifies that operators are to contact the manufacturer for repair 
instructions if any heat damage is found. However, this proposed AD 
would require that the repairs be accomplished in accordance with a 
method approved by the FAA.

Cost Impact

    The FAA estimates that 131 Fokker Model F28 Mark 0070 and Mark 0100 
series airplanes of U.S. registry would be affected by this proposed 
AD, that it would take approximately 1 work hour per airplane to 
accomplish the proposed inspection, and that the average labor rate is 
$60 per work hour. Based on these figures, the cost impact of the 
proposed 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 proposed 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 proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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:

Fokker: 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 
otherwise 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 paragraph (a)(1) and (a)(2) of this 
AD, in accordance with Part 2 of the Accomplishment Instructions of 
the service bulletin:

[[Page 64777]]

    (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 
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.

    Note 3: The subject of this AD is addressed in Dutch 
airworthiness directive BLA No. 1995-087 (A), dated August 31, 1995.

    Issued in Renton, Washington, on December 2, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-32113 Filed 12-8-97; 8:45 am]
BILLING CODE 4910-13-U
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