Airworthiness Directives; Fokker Model F28 Mark 0100 Series Airplanes

DEPARTMENT OF TRANSPORTATION

14 CFR Part 39

[Docket No. 94-NM-118-AD]

Airworthiness Directives; Fokker Model F28 Mark 0100 Series

Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

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 an inspection to detect

cracks in the cleats at certain rib stations of the wing, and

replacement of the cracked cleats with new cleats. This proposal is

prompted by a report that, during manufacture of the wings of these

airplanes, cracks were discovered in the cleats at the left- and right-

hand rib station 8200 of the wing due to improper installation of

certain bolts. The actions specified by the proposed AD are intended to

prevent cracking of the cleats, which could result in reduced

structural integrity of the wing.

DATES: Comments must be received by November 29, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

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

Attention: Rules Docket No. 94-NM-118-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, ANM-

113, Standardization Branch, ANM-113, FAA, Transport Airplane

Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056;

telephone (206) 227-2141; fax (206) 227-1100.

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-118-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-118-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 manufacture of the wings for

the Model F28 Mark 0100 series airplanes, cracks were discovered in the

cleats at the left- and right-hand rib station 8200 of the wing. The

cause of such cracking has been attributed to the improper installation

of certain Hi-lok bolts in the bottom wing skin. This condition, if not

corrected, could result in reduced structural integrity of the wing.

Fokker has issued Service Bulletin SBF100-57-018, dated Septemer

23, 1993, which describes procedures for a high-frequency eddy current

inspection to detect cracks in the cleats at the left and right rib

station 8200 of the wing, and replacement of the cracked cleats with

new cleats. The RLD classified this service bulletin as mandatory and

issued Netherlands Airworthiness Directive BLA 93-142 (A), dated

November 1, 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 a one-time high-

frequency eddy current inspection to detect cracks of the cleats at the

left- and right-hand rib station 8200 of the wing, and replacement of

the cracked cleats with new cleats.

The FAA estimates that 12 airplanes of U.S. registry would be

affected by this proposed AD, that it would take approximately 55 work

hours per airplane to accomplish the proposed actions, and that the

average labor rate is $55 per work hour. Based on these figures, the

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

be $36,300, or $3,025 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-118-AD.

Applicability: Model F28 Mark 0100 series airplanes; as listed

in Fokker Service Bulletin SBF100-57-018, dated September 23, 1993;

certificated in any category.

Compliance: Required as indicated, unless accomplished

previously.

To prevent reduced structural integrity of the wing, accomplish

the following:

(a) Prior to the accumulation of 16,000 total flight cycles or

within 3 months after the effective date of this AD, whichever

occurs later, perform a one-time high-frequency eddy current

inspection to detect cracks in the cleats at the left- and right-

hand rib station 8200 of the wing, in accordance with Fokker Service

Bulletin SBF100-57-018, dated September 23, 1993. If any cracked

cleat is detected, prior to further flight, replace it with a new

cleat, in accordance with the service bulletin.

(b) 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: Information concerning the existence of approved

alternative methods of compliance with this AD, if any, may be

obtained from the Standardization Branch, ANM-113.

(c) 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 October 12, 1994.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 94-25693 Filed 10-17-94; 8:45 am]

BILLING CODE 4910-13-U