[Federal Register Volume 61, Number 43 (Monday, March 4, 1996)]
[Rules and Regulations]
[Pages 8211-8213]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-4669]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-NM-122-AD; Amendment 39-9527; AD 96-05-02]


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 a certain galley; repetitive inspections to 
detect damage and to determine the clearance of generator wires in the 
auxiliary power unit (APU); and repair or replacement of the damaged 
wires. This amendment is prompted by reports indicating that, during an 
unscheduled removal of a galley from the production line, the 
insulation of one of the generator wires of the APU was found damaged 
due to inadequate clearance with the adjacent structure. The actions 
specified by this AD are intended to prevent such damage, which could 
result in a short in the electrical wiring of the APU and, thus, pose a 
potential fire hazard.

DATES: Effective April 3, 1996.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of April 3, 1996.

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 9, 
1994 (59 FR 236). That action proposed to require modification of a 
Nordskog Galley Model 1-871galley. It also proposed to require 
repetitive inspections to detect damage and determine the clearance of 
generator wires in the auxiliary power unit (APU); and repair or 
replacement of the damaged wires.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the single comment received.
    The commenter requests that the rule be revised to delete proposed 
paragraph (a)(2)(i), which would require operators to conduct 
repetitive inspections if the initial inspection shows that no damage 
to the feeder cables exists and that the cables adequately clear the 
adjacent structure. This commenter, an operator, states that it has 
conducted a boroscope inspection of the APU generator cables on all of 
its airplanes, and has found nothing anywhere near the cables that 
could cause damage to them. This operator notes that its initial 
inspection, which was conducted using a flexible boroscope from the 
cockpit, provided an excellent view of both the cables and the drain 
enclosure. The inspection revealed that there is a clearance between 
the wiring and adjacent structure (drain screws) on the order of six 
inches.

[[Page 8212]]

    The FAA concurs with the commenter's request. According to the 
Rijksluchtvaartdienst (RLD), which is the airworthiness authority for 
the Netherlands, the clearance between the drain screws and the APU 
feeder cable (generator wires) found on airplanes on the production 
line was on the order of one inch. This amount of clearance was 
considered to be inadequate, such that chafing or damage of the wire 
installation could occur. Also, according to the RLD, the reason that 
the referenced service bulletin specifies that the inspection be 
accomplished with a mirror is because the manufacturer considered that 
a mirror would give a better estimate of the clearance than could a 
boroscope inspection. However, the FAA, in consultation with the RLD, 
recently has concluded that, since the clearance between the drain 
screws and the wires has been determined to be on the order of 6 inches 
on all affected airplanes that have not already been modified in 
accordance with this AD, there is little reason to believe that chafing 
would occur. In light of this, the FAA finds that there is no need for 
a repetitive inspection of the wires. Therefore, the FAA has revised 
paragraph (a)(2)(i) of the final rule to indicate that, if no wires are 
found damaged as a result of the inspection and they adequately clear 
the adjacent structure (positive clearance), no further inspections are 
required.
    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 with the change previously 
described. The FAA has determined that this change will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.
    The FAA estimates that 52 airplanes of U.S. registry will be 
affected by this proposed AD, that it will take approximately 2 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 $1,000 per airplane. Based on these figures, the cost 
impact of the AD on U.S. operators is estimated to be $58,240, or 
$1,120 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 those actions in the 
future if this AD were not adopted.
    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:

96-05-02  Fokker: Amendment 39-9527. Docket 94-NM-122-AD.

    Applicability: Model F28 Mark 0100 series airplanes; as listed 
in Fokker Service Bulletin SBF100-24-029, dated June 28, 1993; 
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 (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 a short in the electrical wiring of the auxiliary 
power unit (APU) and a potential fire hazard, accomplish the 
following:
    (a) Within 250 flight hours after the effective date of this AD, 
accomplish paragraphs (a)(1) and (a)(2) of this AD.
    (1) Modify Nordskog Galley Model 1-871, in accordance with 
paragraphs 2.A., 2.B., and 2.C. of the Accomplishment Instructions 
of Fokker Service Bulletin SBF100-24-029, dated June 28, 1993.
    (2) Perform an inspection to detect damage of and to determine 
the adequacy of clearance of the generator wires, having part 
numbers (P/N) AJC0001A, AJ0001B, and AJC0001C, of the auxiliary 
power unit (APU), in accordance with Fokker Service Bulletin SBF100-
24-029, dated June 28, 1993.
    (i) If no wires are found damaged and they adequately clear the 
adjacent structure (positive clearance), no further action is 
required by this paragraph.
    (ii) If no wires are found damaged, but they do not adequately 
clear the adjacent structure, repeat the inspection thereafter at 
intervals not to exceed 250 flight hours.
    (iii) If any wire is found damaged, prior to further flight, 
modify the Nordskog Galley Model 1-871 in accordance with paragraph 
(b) of this AD, and repair or replace the damaged wire in accordance 
with the service bulletin. However, the modification and repair/
replacement actions may be postponed for a maximum of 10 days after 
detection of the damage, provided that the APU generator is rendered 
inoperative in accordance with the Master Minimum Equipment List 
(MMEL), and that modification and repair/replacement actions are 
accomplished prior to reactivation of the APU generator.
    (b) At the next removal of the Nordskog Galley Model 1-871, or 
within 9,000 flight hours after the effective date of this AD, 
whichever occurs first, modify the Nordskog Galley in accordance 
with Fokker Service Bulletin SBF100-24-029 (reference Nordskog 
Engineering Change Order 43589 Attachment), dated June 28, 1993. 
Accomplishment of this modification constitutes terminating action 
for the repetitive inspection requirements of this AD.
    (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, 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.


[[Page 8213]]

    (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.
    (e) The actions shall be done in accordance with Fokker Service 
Bulletin SBF100-24-029, dated June 28, 1993, including Nordskog 
Engineering Change Order 43589 Attachment. 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.
    (f) This amendment becomes effective on April 3, 1996.

    Issued in Renton, Washington, on February 23, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-4669 Filed 3-1-96; 8:45 am]
BILLING CODE 4910-13-U