[Federal Register Volume 61, Number 250 (Friday, December 27, 1996)]
[Rules and Regulations]
[Pages 68131-68132]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-31526]



[[Page 68131]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-NM-58-AD; Amendment 39-9852; AD 96-25-09]
RIN 2120-AA64


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

DATES: Effective January 31, 1997.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of January 31, 1997.

ADDRESSES: The service information referenced in this AD may be 
obtained from Fokker Aircraft USA, Inc., 1199 North Fairfax Street, 
Alexandria, Virginia 22314. 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: 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: 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 certain Fokker Model F28 Mark 0100 
series airplanes was published in the Federal Register on December 4, 
1995 (60 FR 62051). That action proposed to require modification of the 
thrust reverser doors. That action also proposed to 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.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Support for the Proposal

    One commenter supports the proposed AD.

Request To Revise Compliance Time

    One commenter requests that the compliance time for accomplishing 
the modification be revised from the proposed ``prior to the 
accumulation of 15,000 total flight cycles or within 1 year after the 
effective date of the AD, whichever is later,'' to ``prior to the 
accumulation of 16,000 total flight cycles or within 2 years after the 
effective date of the AD, whichever is later.'' This commenter states 
that the interval for its regular heavy maintenance (``Q'' check) is 
expected to be escalated in the near future to 16,000 flight hours/
cycles; if the compliance time of the AD is extended likewise, it will 
allow this commenter to modify its fleet of affected airplanes during 
this regularly scheduled heavy maintenance interval. The commenter 
notes that, since the modification takes approximately 300 work hours 
to complete, it would be more economical to accomplish the modification 
during regularly scheduled maintenance, rather than having to schedule 
special times for the modification to be done. The commenter also 
states that, if it were required to bring its airplanes in for 
modification at a time other than the ``Q'' check interval, the 
associated costs would be far more than what the FAA indicated in its 
``cost impact'' information that appeared in the preamble to the 
notice. Further, this commenter states that 6 of its 40 affected 
airplanes already have gone through their ``Q'' checks without having 
the modification installed; and if those 6 airplanes were required to 
be modified within 1 year, this commenter would sustain significant 
economic and logistical burdens.
    The FAA does not concur with the commenter's request. The 
compliance time specified in the notice was developed in consultation 
with both the Rijksluchtvaartdienst (RLD), which is the airworthiness 
authority for the Netherlands, and Fokker. Based on fatigue test 
results and analysis of the effects of the thrust reverser loads on 
adjacent structure, the FAA has determined that 15,000 flight cycles is 
the maximum number of cycles that these airplanes can be allowed to 
operate prior to modification without compromising safety. The 
commenter has submitted no technical data to justify its request for an 
extension of this limit by 1,000 additional flight cycles. Although the 
FAA does consider the maintenance schedules of affected operators when 
developing appropriate compliance times for AD actions, it does not 
revise AD's merely to accommodate individual operators' maintenance 
schedules.
    Additionally, the FAA disagrees with the commenter's statement that 
the modification takes 300 work hours to complete. The cost impact 
information that appeared in the preamble to the notice (and in this 
final rule, below) indicated that only 127 work hours were necessary to 
complete the modification. That figure was based on information 
provided by the manufacturer, and was conservatively estimated based on 
performing options that take the longest time to accomplish. Further, 
the manufacturer estimates that the total elapsed time necessary to 
accomplish the modification is only 67 hours, since more than one 
person can perform the work.

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 102 Fokker Model F28 Mark 0100 series 
airplanes of U.S. registry will be affected by this AD, that it will 
take approximately 127 work hours per airplane to accomplish the 
required actions, and that the average labor rate is $60 per work hour. 
Required parts will cost approximately $19,000 per airplane. Based on 
these figures, the cost impact of the 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 requirements of this AD 
action, and that no operator would accomplish

[[Page 68132]]

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:
96-25-09 Fokker: Amendment 39-9852. 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 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.
    (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.
    (f) The actions shall be done in accordance with Fokker Service 
Bulletin SBF100-31-036, dated February 7, 1994; Fokker Service 
Bulletin SBF100-31-038, dated April 26, 1994; and Fokker Service 
Bulletin SBF100-78-010, Revision 1, dated April 26, 1994, which 
contains the following list of effective pages:

------------------------------------------------------------------------
                                    Revision level                      
           Page number               shown on page    Date shown on page
------------------------------------------------------------------------
1-6, 8, 10, 11..................  1.................  April 26, 1994.   
7, 9, 12-14.....................  Original..........  February 7, 1994. 
------------------------------------------------------------------------

    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 Aircraft USA, Inc., 1199 
North Fairfax Street, Alexandria, Virginia 22314. 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.
    (g) This amendment becomes effective on January 31, 1997.

    Issued in Renton, Washington, on December 5, 1996.
S. R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-31526 Filed 12-26-96; 8:45 am]
BILLING CODE 4910-13-U