Airworthiness Directives; Fokker Model F28 Mark 0100 Series Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-122-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 a certain

galley; 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. This proposal would also

require an additional modification of a certain galley, which would

terminate the repetitive inspection requirements. This proposal is

prompted by reports that, during an unscheduled removal of a certain

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 the proposed 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: Comments must be received by February 7, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

Administration (FAA), Transport Airplane Directorate, ANM-103,

Attention: Rules Docket No. 94-NM-122-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: 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) 227-1320.

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 94-NM-122-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. 94-NM-122-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 an unscheduled removal of a

Nordskog Galley Model No. 1-871 from the production line, the

insulation of one of the generator wires of the auxiliary power unit

(APU) was found to be damaged. The cause of such damage has been

attributed to inadequate clearance between the generator wires and

adjacent structure. This condition, if not corrected, could result in a

short in the electrical wiring of the APU and, thus, pose a potential

fire hazard.

Fokker has issued Service Bulletin SBF100-24-029, dated June 28,

1993, which describes procedures for modification of Nordskog Galley

Model 1-871 to replace a bolt; repetitive inspections to detect damage

and determine the adequacy of clearance between the generator wires,

having part numbers (P/N) AJC0001A, AJ0001B, and AJC0001C, of the APU

and the adjacent structure; and repair or replacement of the damaged

wires. This service bulletin also contains an attachment (Nordskog

Engineering Change Order 43589, dated May 20, 1993) that describes

procedures for modification of the Nordskog Galley Model 1-871. This

modification involves removing existing screws and ``T'' nuts and

installing new screws, washers, and nuts inside the cart compartment of

the rear galley. This modification would eliminate the need for the

repetitive inspections. The RLD issued Netherlands airworthiness

directive BLA 93-117 (A), dated September 10, 1993, 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

Nordskog Galley Model 1-871 to replace a specific bolt; repetitive

inspections to detect damage and determine the adequacy of clearance of

certain generator wires of the APU; and repair or replacement of the

damaged wires. This proposed AD would also require an additional

modification of the Nordskog Galley Model 1-871, which, when

accomplished, would constitute terminating action for the repetitive

inspection requirements. The actions would be required to be

accomplished in accordance with the service bulletin described

previously.

As a result of recent communications with the Air Transport

Association (ATA) of America, the FAA has learned that, in general,

some operators may misunderstand the legal effect of AD's on airplanes

that are identified in the applicability provision of the AD, but that

have been altered or repaired in the area addressed by the AD. The FAA

points out that all airplanes identified in the applicability provision

of an AD are legally subject to the AD. If an airplane has been altered

or repaired in the affected area in such a way as to affect compliance

with the AD, the owner or operator is required to obtain FAA approval

for an alternative method of compliance with the AD, in accordance with

the paragraph of each AD that provides for such approvals. A note has

been included in this notice to clarify this requirement.

-The FAA estimates that 52 airplanes of U.S. registry would be

affected by this proposed AD, that it would take approximately 2 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 $1,000 per airplane. Based on these figures, the total

cost impact of the proposed AD on U.S. operators is estimated to be

$58,240, or $1,120 per airplane.

The total 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. 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. App. 1354(a), 1421 and 1423; 49 U.S.C.

106(g); and 14 CFR 11.89.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding the following new

airworthiness directive:

Fokker: 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 use the authority

provided in paragraph (c) 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 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 and 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), repeat the inspection

thereafter at intervals not to exceed 3,000 flight hours.

-(ii) If no wires are found damaged and 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.

-(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.

Issued in Renton, Washington, on December 5, 1994.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 94-30399 Filed 12-8-94; 8:45 am]

BILLING CODE 4910-13-U