AD 94-08-09

This amendment adopts a new airworthiness directive (AD), applicable to Jetstream Model ATP airplanes, that requires a one-time inspection and appropriate torque loading check of certain wing top surface stringer joint fasteners, and correction of discrepancies. This amendment is prompted by a report of loose fasteners on the wing top surface stringer joint bolts at Rib 0. The actions specified by this AD are intended to prevent reduced structural integrity of the wing top surface stringer joints at Rib 0, which subsequently could lead to reduced structural integrity of the wing.

Final rule

94-08-09 JETSTREAM AIRCRAFT LIMITED (formerly British Aerospace): Amendment 39-8881. Docket 93-NM-186-AD.
Applicability: Model ATP airplanes; serial numbers 2001 through 2053 inclusive, and 2055; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent reduced structural integrity of the wing top surface stringer joints at Rib 0, which subsequently could lead to reduced structural integrity of the wing, accomplish the following:

(a) Prior to the accumulation of 10,000 total hours time-in-service, or within the next 600 hours time-in-service after the effective date of this AD, whichever occurs later, perform a detailed visual inspection and appropriate torque loading check of the fasteners in the stringer joint brackets (part number JD534J0015) at the wing top surface stringer joints for stringers 1 through 19 at Rib 0, in accordance with paragraph 2.A. of British Aerospace BAe ATP Service Bulletin ATP-57-14, Revision 1, dated September 27, 1993; or Revision 3, dated December 15, 1993. If any discrepancy, as specified in the service bulletin, is detected, prior to further flight, correct it 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 Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the airplane to a location where the requirementsof this AD can be accomplished.

(d) The inspection, torque loading check, and correction of discrepancies shall be done in accordance with the following British Aerospace BAe ATP Service Bulletins, which contain the specified list of effective pages:

Service Bulletin
Number and Date
Page Number
Revision Level
Shown on Page
Date
Shown on Page

ATP-57-14
Revision 1
1-3
1
September 27, 1993
September 27, 1993
4-5, 7, 9, 11,
13, 15
0
August 14, 1993

6, 8, 10, 12, 14
(These pages are not used.)

ATP-57-14
Revision 3
1-2
3
December 15, 1993
December 15, 1993
3-5
2
November 24, 1993

7, 9, 11, 13,
15
0
August 14, 1993

6, 8, 10, 12,
14
(These pages are not used.)

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 Jetstream Aircraft, Inc., Librarian for Service Bulletins, P.O. Box 16029, Dulles International Airport, Washington, DC 20041-6029. 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.

(e) This amendment becomes effective on June 6, 1994.

A proposal to amend part 39 of the Federal Aviation Regulations to include an airworthiness directive (AD) that is applicable to Jetstream Model ATP airplanes was published in the Federal Register on December 15, 1993 (58 FR 65569). That action proposed to require a one-time inspection and appropriate torque loading check of certain wing top surface stringer joint fasteners, and correction of discrepancies.

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 supports the proposal.

Since issuance of the notice, Jetstream Aircraft Limited has issued Revision 3 of BAe ATP Service Bulletin ATP-57-14, dated December 15, 1993. This revision of the service bulletin is essentially identical to Revision 1, which was referenced in the notice, but contains certain editorial changes. The FAA has revised the final rule to include a reference to Revision 3 of the service bulletin as an additional source of appropriate service information.

After careful review of the available data, including the comment 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 10 airplanes of U.S. registry will be affected by this AD, that it will take approximately 50 work hours per airplane to accomplish the required actions, and that the average labor rate is $55 per work hour. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $27,500, or $2,750 per airplane.

The total 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 operatorwould 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" qunder 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 14 CFR part 39 of the Federal Aviation Regulations 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.

39.13 - [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: