[Federal Register Volume 60, Number 232 (Monday, December 4, 1995)]
[Proposed Rules]
[Pages 62051-62053]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-29443]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-NM-58-AD]


Airworthiness Directives; Fokker Model F28 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 certain Fokker Model F28 Mark 0100 
series airplanes. This proposal would require modification of the 
thrust reverser doors, and replacement of the Collins multifunction 
display units (MFDU) with new MFDU's. This proposal would also require 
installation of a placard, for certain airplanes. This proposal is 
prompted by a report that cracks were found in the flanges of the main 
hinge fittings of the horizontal stabilizer due to higher than 
anticipated loads induced during thrust reverser operation. The actions 
specified by the proposed AD are intended to ensure structural 
integrity of the horizontal stabilizer by reducing the thrust reverser 
loads on the horizontal stabilizer.

DATES: Comments must be received by January 16, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 95-NM-58-AD, 1601 Lind Avenue SW., Renton, 
Washington 98055-4056. Comments 

[[Page 62052]]
may be inspected at this location between 9 a.m. and 3 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: Tim Dulin, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone (206) 
227-2141; 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 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 95-NM-58-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. 95-NM-58-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 F28 Mark 0100 series 
airplanes. The RLD advises that, during full scale fatigue testing of 
the horizontal and vertical stabilizers, cracks were found in the 
flanges of the left- and right-hand main hinge fittings of the 
horizontal stabilizer on a Model F28 Mark 0100 test article. 
Investigation revealed that such cracking is the result of higher than 
anticipated loads induced on the tail of the airplane during thrust 
reverser operation. This condition, if not corrected, could lead to a 
deteriorated fatigue life of the main hinge fitting structure on the 
horizontal stabilizer and reduced structural integrity of the 
horizontal stabilizer.
    Fokker has issued Service Bulletin SBF100-78-010, Revision 1, dated 
April 26, 1994, which describes procedures for modification of the 
thrust reverser doors. This modification involves installation of 
extended bumper fittings on the thrust reverser doors. Accomplishment 
of this modification will reduce the reverse thrust at a given engine 
pressure ratio by increasing the spillage gap.
    Fokker has also issued Service Bulletin SBF100-31-036, dated 
February 7, 1994, which describes procedures for replacement of the 
Collins multifunction display units (MFDU) having part number (P/N) 
622-8047-412 or 622-8047-422 with new MFDU's having P/N 622-8047-414 or 
622-8047-423, respectively. Accomplishment of this replacement will 
reduce thrust reverser loads on the horizontal stabilizer.
    Additionally, Fokker has issued Service Bulletin SBF100-31-038, 
dated April 26, 1994, which describes procedures for installation of a 
placard on the main instrument panel, if the replacement of the MFDU is 
accomplished prior to modification of the thrust reverser door. The 
placard provides current engine limits for these airplanes.
    The RLD classified these service bulletins as mandatory and issued 
Netherlands airworthiness directive BLA 94-062(A), dated April 29, 
1994, in order to assure the continued airworthiness of these airplanes 
in the Netherlands.
    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.
    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 modification of the 
thrust reverser doors. The proposed AD would also require replacement 
of certain Collins multifunction display units (MFDU) with certain new 
MFDU's, and installation of a placard, if the replacement of the MFDU 
is accomplished prior to modification of the thrust reverser door. The 
actions would be required to be accomplished in accordance with the 
service bulletins described previously.
    The FAA estimates that 102 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 127 work 
hours per airplane to accomplish the proposed actions, and that the 
average labor rate is $60 per work hour. Required parts would cost 
approximately $19,000 per airplane. Based on these figures, the cost 
impact of the proposed AD on U.S. operators is estimated to be 
$2,715,240, or $26,620 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.
    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. 

[[Page 62053]]
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), 40101, 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

Fokker: Docket 95-NM-58-AD.

    Applicability: Model F28 Mark 0100 series airplanes; serial 
numbers 11244 through 11460 inclusive, 11463 through 11469 
inclusive, 11471, 11474, 11476, 11478, and 11479; 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 use the authority 
provided in paragraph (d) of this AD to request approval from the 
FAA. This approval may address either no action, if the current 
configuration eliminates the unsafe condition; or different actions 
necessary to address the unsafe condition described in this AD. Such 
a request should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any airplane from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To ensure structural integrity of the horizontal stabilizer by 
reducing the thrust reverser loads on the horizontal stabilizer, 
accomplish the following:
    (a) Prior to the accumulation of 15,000 total flight cycles, or 
within 1 year after the effective date of this AD, whichever occurs 
later, accomplish the requirements of paragraphs (a)(1) and (a)(2) 
of this AD concurrently, except as provided by paragraph (b) of this 
AD.
    (1) Modify the thrust reverser doors in accordance with Fokker 
Service Bulletin SBF100-78-010, Revision 1, dated April 26, 1994; 
and
    (2) Replace the Collins multifunction display units (MFDU) 
having part number (P/N) 622-8047-412 or 622-8047-422 with new 
MFDU's having P/N 622-8047-414 or 622-8047-423, respectively; as 
applicable; in accordance with Fokker Service Bulletin SBF100-31-
036, dated February 7, 1994.
    (b) Paragraph (a)(2) of this AD may be accomplished prior to 
paragraph (a)(1) of this AD provided that a placard is installed on 
the main instrument panel in accordance with Fokker Service Bulletin 
SBF100-31-038, dated April 26, 1994, and removed, prior to further 
flight, after accomplishment of the requirements of paragraph (a)(1) 
of this AD.
    (c) For airplanes that have been modified in accordance with 
paragraphs (a)(1) and (a)(2) of this AD: No person may install a 
Grumman Aerospace aft engine cowling having part number 1159P41440 
on any airplane unless it has been previously modified in accordance 
with Fokker Component Service Bulletin P41440-78-02, dated December 
17, 1993, as revised by Fokker Component Service Bulletin Change 
Notification P41440-78-02/001, dated February 25, 1995.
    (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 November 28, 1995.
S. R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-29443 Filed 12-1-95; 8:45 am]
BILLING CODE 4910-13-U