[Federal Register Volume 62, Number 243 (Thursday, December 18, 1997)]
[Proposed Rules]
[Pages 66317-66319]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-32996]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-290-AD]
RIN 2120-AA64


Airworthiness Directives; Fokker Model F28 Mark 1000, 2000, 3000, 
and 4000 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 certain Fokker Model F28 Mark 
1000, 2000, 3000, and 4000 series airplanes. This proposal would 
require replacement of certain hinges on the forward, center, and aft 
cargo doors with improved hinges. 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 failure of the cargo door hinges caused by stress 
corrosion or fatigue cracks, which could result in decompression of the 
airplane, and possible in-flight separation of the cargo door.

DATES: Comments must be received by January 20, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 97-NM-290-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 Service 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-290-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-290-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 certain Fokker Model F28 Mark 1000, 2000, 3000, 
and 4000 series airplanes. The RLD advises that it has received reports 
of fracturing of the cargo door hinges due to stress corrosion. 
Approximately one-half of the lugs of the fuselage-mounted hinge were 
cracked on one airplane. In addition, the RLD received one report of 
fatigue cracks in the cargo door hinge on a test article. These 
conditions, if not corrected, could result in failure of the cargo door 
hinges, which could result in decompression of the airplane, and 
possible in-flight separation of the cargo door.

[[Page 66318]]

Explanation of Relevant Service Information

    Fokker has issued Service Bulletin F28/52-110, dated April 7, 1993, 
which describes procedures for replacement of the hinges on the 
forward, center, and aft cargo doors with improved hinges made of a 
material that is less sensitive to stress corrosion. Accomplishment of 
the replacement is intended to adequately address the identified unsafe 
condition. The RLD classified this service bulletin as mandatory and 
issued Dutch airworthiness directive 93-055 (A), dated April 23, 1993, 
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 Sec. 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 bulletin described previously, 
except as described below.

Differences Between the Proposal and the Related Service Bulletin

    Operators should note that this AD proposes to require replacement 
of the hinges on the forward, center, and aft cargo doors within 12 
months. The Fokker service bulletin described previously recommends 
that the replacement be accomplished within four years from the date of 
issuance of the service bulletin. However, the FAA has determined that, 
due to the safety implications and consequences associated with such 
cracking, a shorter compliance time of 12 months is necessary.

Cost Impact

    The FAA estimates that 37 airplanes of U.S. registry would be 
affected by this proposed AD.
    It would take approximately 62 work hours per airplane to replace 
the forward cargo door hinge, at an average labor rate of $60 per work 
hour. Required parts would cost approximately $5,740 per airplane. 
Based on these figures, the cost impact of this replacement proposed by 
this AD on U.S. operators is estimated to be $350,020, or $9,460 per 
airplane.
    It would take approximately 62 work hours per airplane to replace 
the center cargo door hinge, at an average labor rate of $60 per work 
hour. Required parts would cost approximately $5,650 per airplane. 
Based on these figures, the cost impact of this replacement proposed by 
this AD on U.S. operators is estimated to be $346,690, or $9,370 per 
airplane.
    It would take approximately 46 work hours per airplane to replace 
the aft cargo door hinge, at an average labor rate of $60 per work 
hour. Required parts would cost approximately $6,470 per airplane. 
Based on these figures, the cost impact of this replacement proposed by 
this AD on U.S. operators is estimated to be $341,510, or $9,230 per 
airplane.
    The cost impact figures discussed above are 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-290-AD.

    Applicability: Model F28 Mark 1000, 2000, 3000, and 4000 series 
airplanes; serial numbers 11003 through 11241 inclusive, 11991, and 
11992; 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 (b) 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 failure of the cargo door hinges caused by stress 
corrosion and/or fatigue cracks, which could result in decompression 
of the airplane, and possible in-flight separation of the cargo 
door; accomplish the following:
    (a) Within 12 months after the effective date of this AD, 
replace the hinges on the forward, center, and aft belly cargo doors 
with improved hinges in accordance with Part 1, Part 2, and Part 3, 
as applicable, of the Accomplishment Instructions of Fokker Service 
Bulletin F28/52-110, dated April 7, 1993.
    (b) 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,

[[Page 66319]]

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.

    (c) Special flight permits may be issued in accordance with 
Secs. 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 93-055 (A), dated April 23, 1993.

    Issued in Renton, Washington, on December 11, 1997.
Gilbert L. Thompson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-32996 Filed 12-17-97; 8:45 am]
BILLING CODE 4910-13-U