AD 94-24-09 R1

This amendment revises an existing airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that currently requires repetitive inspections to detect damage to the overwing fairings, and replacement or repair of structurally damaged fairings. That AD was prompted by a report indicating that an overwing fairing detached from an airplane. The actions specified by that AD are intended to prevent reduced controllability of the airplane due to loss of an overwing fairing. This amendment adds an optional terminating action for the currently required inspections, and limits the applicability of the rule.

Final rule

94-24-09 R1 JETSTREAM AIRCRAFT LIMITED: Amendment 39-9536. Docket 95-NM-71-AD. Revises AD 94-24-09, Amendment 39-9082.
Applicability: Model 4101 airplanes; constructor's number 41004 and subsequent; on which Modification JM41392 has not been installed (either during production or in accordance with Jetstream Service Bulletin J41-53-031); 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 reduced controllability of the airplane, accomplish the following:

(a) Within 7 days after December 14, 1994 (the effective date of AD 94-24-09, amendment 39-9082), perform a detailed visual inspection to detect structural damage (such as creasing, cracking, or holes) to the left (Part 1) and right (Part 2) overwing fairings, in accordance with Jetstream Alert Service Bulletin J41-53-028, Revision 1, dated October 12, 1994; or Revision 2, dated January 17, 1995.

(1) If no structural damage is detected, repeat the inspection thereafter at intervals not to exceed 7 days.

(2) If creasing or cracking is detected, prior to further flight, inspect and repair it, in accordance with the alert service bulletin. Repeat the inspection thereafter at intervals not to exceed 300 hours time-in-service.

NOTE 2: Jetstream Alert Service Bulletin J41-53-028 references British Aerospace Public Limited Company Drawing 141R0700, Issue 3, dated September 14, 1994, and British Aerospace Public Limited Company Drawing 141R0705, Issue 2, dated September 22, 1994, for repair and inspection procedures.

(3) If holes are detected, prior to further flight, repair in accordance with the Jetstream Series 4100 Structural Repair Manual. Repeat the inspection thereafter at intervals not to exceed 300 hours time-in-service.

(b) Installation of Modification No. JM41392, Parts 1 and 2, in accordance with Jetstream Service Bulletin J41-53-031, dated November 22, 1994, constitutes terminating action for the inspections required by paragraph (a) 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, TransportAirplane 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 3: 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.

(e) The inspections and repair shall be done in accordance with Jetstream Alert Service Bulletin J41-53-028, Revision 1, dated October 12, 1994; or Jetstream Alert Service Bulletin J41-53-028, Revision 2, dated January 17, 1995, which contains the following list of effective pages:

Page Number
Revision Level
Shown on Page
Date
Shown on Page
1, 3, 5, 6
2
January 17, 1995
2, 4, 7, 8
Original
September 22, 1994

The incorporation by reference of Jetstream Alert Service Bulletin J41-53-028, Revision 1, dated October 12, 1994, was previously approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51 as of December 14, 1995 (59 FR 60891, November 29, 1994). The incorporation by reference of Jetstream Alert Service Bulletin J41-53-028, Revision 2, dated January 17, 1995, is 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., 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.

(f) This amendment becomes effective on April 10, 1996.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by revising AD 94-24-09, amendment 39-9082 (59 FR 60891, November 29, 1994), which is applicable to certain Jetstream Model 4101 airplanes, was published in the Federal Register on October 11, 1995 (60 FR 52870). The action proposed to revise AD 94-24-09 to continue to require repetitive inspections to detect damage to the overwing fairings, and replacement or repair of structurally damaged fairings. The action also proposed to provide an optional terminating action for the repetitive inspections.

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 proposed rule.

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 adoptionof the rule as proposed.

The FAA estimates that 14 airplanes of U.S. registry will be affected by this AD.

The inspections currently required by AD 94-24-09 take approximately 0.25 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the current inspection requirements of this AD on U.S. operators is estimated to be $210, or $15 per airplane, per inspection.

Should an operator elect to install the optional terminating modification, it will take approximately 20 work hours to accomplish, at an average labor rate of $60 per work hour. Required parts will cost approximately $7,300 per airplane. Based on these figures, the cost impact of this optional terminating modification on U.S. operators is estimated to be $8,500 per airplane.

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, Incorporationby 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 USC 106(g), 40113, 44701.

39.13 - [Amended]
2. Section 39.13 is amended by removing amendment 39-9082 (59 FR 60891, November 29, 1994), and by adding a new airworthiness directive (AD), amendment 39-9536, to read as follows: