[Federal Register Volume 61, Number 143 (Wednesday, July 24, 1996)]
[Proposed Rules]
[Pages 38407-38409]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-18773]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-NM-28-AD]
RIN 2120-AA64


Airworthiness Directives; Fokker Model F27 Mark 100, 200, 300, 
400, 500, 600, and 700 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 F27 Mark 100, 
200, 300, 400, 500, 600, and 700 series airplanes. This proposal would 
require a one-time visual inspection to detect missing rivet heads or 
loose rivets of the applicable stringer-to-rib connections in the upper 
and lower wing skin, and repair, if necessary. In lieu of the one-time 
visual inspection or in addition to that inspection, the proposed AD 
also would require replacement of certain rivets with certain new 
rivets in all applicable rib-to-stringer connections of the upper and 
lower wings. This proposal is prompted by reports of missing rivet 
heads at the rib-to-stringer connections of the upper and lower wing 
skin at stringers 5 and 6. The actions specified by the proposed AD are 
intended to prevent reduced structural integrity of the wings that is 
caused by problems associated with missing and/or loose rivets.

DATES: Comments must be received by September 3, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 96-NM-28-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 Aircraft USA, Inc., 1199 North Fairfax Street, 
Alexandria, Virginia 22314. This information may be examined at the 
FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Ruth E. Harder, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-1721; fax (206) 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

[[Page 38408]]

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 96-NM-28-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. 96-NM-28-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Rijksluchtvaartdienst (RLD), which is the airworthiness 
authority for the Netherlands, recently notified the FAA that an unsafe 
condition may exist on certain Fokker Model F27 Mark 100, 200, 300, 
400, 500, 600, and 700 series airplanes. The RLD advises that it has 
received two reports indicating that the rivet heads were missing at 
the rib-to-stringer connections of the upper and lower wing skin at 
stringers 5 and 6, at wing stations 11260, 11860, 12660, and 13460. 
These incidents occurred on two airplanes that had accumulated 11,601 
and 15,684 total flight cycles, respectively. Investigation revealed 
that the rivets on these airplanes have a lower than allowable tensile 
strength, which contributes to these rivets becoming loosened over 
time. Loose or missing rivets at the subject attachment areas could 
result in reduced structural integrity of the wing.

Relevant Service Information

    Fokker has issued Service Bulletin F27/57-74, dated November 15, 
1994, which describes procedures for a one-time visual inspection to 
detect missing rivet heads or loose rivets of the applicable stringer-
to-rib connections in the upper and lower skin, and repair, if 
necessary. In lieu of one-time visual inspection, or in addition to 
that inspection, the service bulletin also contains procedures for 
replacement of rivets having part number (P/N) MS20600AD4W2 with new 
rivets having P/N CR3553P4 in all applicable rib-to-stringer 
connections of the upper and lower wings. The RLD classified this 
service bulletin as mandatory and issued Dutch airworthiness directive 
BLA 93-094 (A), dated July 16, 1993, in order to assure the continued 
airworthiness of these airplanes in the Netherlands.

FAA's Conclusions

    This airplane model is manufactured in the Netherlands and is 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 Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design, the 
proposed AD would require a one-time visual inspection to detect 
missing rivet heads or loose rivets of the applicable stringer-to-rib 
connections in the upper and lower skin, and repair, if necessary. In 
lieu of the one-time visual inspection, or in addition to that 
inspection, the proposed AD would require replacement of certain rivets 
with certain new rivets in all applicable rib-to-stringer connections 
of the upper and lower wings. The actions would be required to be 
accomplished in accordance with the service bulletin described 
previously.

Cost Impact

    The FAA estimates that 6 Fokker Model 100, 200, 300, 400, 500, 600, 
and 700 series airplanes of U.S. registry would be affected by this 
proposed AD.
    The proposed inspection would take approximately 4 work hours per 
airplane to accomplish the proposed actions, at an average labor rate 
of $60 per work hour. Based on these figures, the cost impact of the 
proposed inspection action on U.S. operators is estimated to be $240 
per airplane.
    The proposed replacement would take approximately 19 work hours per 
airplane to accomplish the proposed actions, at an average labor rate 
of $60 per work hour. The cost of required parts would be nominal. 
Based on these figures, the cost impact of the replacement proposed AD 
on U.S. operators is estimated to be $1,140 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 96-NM-28-AD.

    Applicability: Model F27 Mark 100, 200, 300, 400, 500, 600, and 
700 series airplanes, serial numbers 10653 through 10692

[[Page 38409]]

inclusive; on which Part 1 of the Accomplishment Instructions of 
Fokker Service Bulletins F27/57-68 and F27/57-70 has not been 
accomplished; 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 (d) 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 loose or missing rivets at the rib-to-stringer 
connections of the upper and lower wing skin at stringers 5 and 6, 
which could result in reduced structural integrity of the wings, 
accomplish the following:
    (a) Except as provided by paragraph (c) of this AD: Prior to the 
accumulation of 10,000 total flight cycles, or within 2 months after 
the effective date of this AD, whichever occurs later, perform a 
one-time visual inspection to detect missing rivet heads or loose 
rivets of the applicable stringer-to-rib connections in the upper 
and lower skin, in accordance with Part 2 of the Accomplishment 
Instructions of Fokker Service Bulletin F27/57-74, dated November 
15, 1994.
    (1) If no missing rivet head and no loose rivet is detected, no 
further action is required by paragraph (a) of this AD.
    (2) If any missing rivet head or loose rivet is detected, prior 
to further flight, repair the affected rib-to-stringer connection, 
in accordance with Part 1 of the Accomplishment Instructions of the 
service bulletin.
    (b) Prior to the accumulation of 10,000 total flight cycles, or 
within 1 year after the effective date of this AD, whichever occurs 
later, replace rivets having part number (P/N) MS20600AD4W2 with new 
rivets having P/N CR3553P4 in all applicable rib-to-stringer 
connections of the upper and lower wings, in accordance with Part 1 
of the Accomplishment Instructions of Fokker Service Bulletin F27/
57-74, dated November 15, 1994.
    (c) Airplanes on which the replacement required by paragraph (b) 
of this AD is performed within the compliance time specified in 
paragraph (a) of this AD are not required to accomplish the 
inspection required by paragraph (a) of this AD.
    (d) 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, Standardization Branch, ANM-113, 
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, 
Standardization Branch, ANM-113.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (e) 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.

    Issued in Renton, Washington, on July 18, 1996.
Stewart R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-18773 Filed 7-23-96; 8:45 am]
BILLING CODE 4910-13-P