AD 95-17-10

This amendment adopts a new airworthiness directive (AD) that applies to certain Jetstream Aircraft Limited (JAL) Jetstream Models 3101 and 3201 airplanes. This action requires modifying the central annunciator panel test button circuit. A report of diode failure in this circuit and subsequent inadvertent engine shutdown on one of the affected airplanes prompted this action. The actions specified by this AD are intended to prevent failure of a diode in the central annunciator panel test button circuit, which could result in inadvertent engine shutdown while in flight if the central annunciator panel test button is pressed.

Final rule

95-17-10 JETSTREAM AIRCRAFT LIMITED: Amendment 39-9340; Docket No. 91-CE-85-AD.
Applicability: Jetstream Model 3101 airplanes, all serial numbers, and Jetstream Model 3201 airplanes, serial numbers 790 through 950, 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 (d) of this AD 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 within the next 200 hours time-in-service after the effective date of this AD, unless already accomplished.

To prevent failure of a diode in the central annunciator panel test button circuit, which could result in inadvertent engine shutdown while in flight if the central annunciator panel test button is pressed, accomplish the following:

(a) Modify the central annunciator panel test button circuit (Amendment JA 911045) by removing diodes from the engine stop circuit and configuring a minor wiring change in accordance with PART 2 of the ACCOMPLISHMENT INSTRUCTIONS section of Jetstream Alert Service Bulletin 80-A-JA 911045, Revision 1, dated November 1, 1991.

(b) As noted in Jetstream Alert Service Bulletin 80-A-JA 911045, Revision 1, dated November 1, 1991, terminals may be linkedusing 22 AWA cable and terminal tags, provided the following is accomplished:

(1) For airplanes without roof panel plug breaks, identify the cables as WQ69 and WQ70.

(2) For airplanes with roof panel plug breaks, identify the cables as WQ71 and WQ72.

(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.

(d) An alternative method of compliance or adjustment of the compliance time that provides an equivalent level of safety may be approved by the Manager, Brussels Aircraft Certification Office (ACO), Europe, Africa, Middle East office, FAA, c/o American Embassy, B-1000 Brussels, Belgium. The request should be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Brussels ACO.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Brussels ACO.

(e) The modification required by this AD shall be done in accordance with Jetstream Alert Service Bulletin 80-A-JA 911045, Revision 1, dated November 1, 1991. 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 Limited, Manager Product Support, Prestwick Airport, Ayrshire, KA9 2RW Scotland; or Jetstream Aircraft Inc., Librarian, P.O. Box 16029, Dulles International Airport, Washington, DC, 20041-6029. Copies may be inspected at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW., 7th Floor, suite 700, Washington, DC.

(f) This amendment becomes effective on October 3, 1995.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to certain JAL Jetstream Models 3101 and 3201 airplanes was published in the Federal Register on April 11, 1995 (60 FR 18376). The action proposed to require modifying the central annunciator panel test button circuit by removing diodes from the engine stop circuit and configuring a minor wiring change. Accomplishment of the proposed actions would be in accordance with Jetstream Alert Service Bulletin 80-A-JA 911045, Revision 1, dated November 1, 1991.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposed rule or the FAA's determination of the cost to the public.

After careful review of all available information related to the subject presented above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed except for minor editorial corrections. The FAA has determined that these minor corrections will not change the meaning of the AD and will not add any additional burden upon the public than was already proposed.

The FAA estimates that 260 airplanes in the U.S. registry will be affected by this AD, that it will take approximately 2 workhours per airplane to accomplish the required modification, and that the average labor rate is approximately $60 an hour. JAL will provide parts at no cost to the owner/operator. Based on these figures, the total cost impact of this AD on U.S. operators is estimated to be $31,200. This figure is based on the assumption that no affected owner/operator has incorporated the required modification.

JAL has informed the FAA that 2 modification kits have been distributed to affected airplane owners/operators. Assuming that each of these modification kits has been incorporated on an affected airplane, then the cost impact upon U.S. operators would be reduced $240 (2 workhours X $60 per hour X 2 airplanes) from $31,200 to $30,960. The FAA also believes that numerous owners/operators of the affected airplanes have accomplished the modification using 22AWA cable and terminal tags instead of obtaining parts from the manufacturer, as is provided for in this AD. This would further reduce the cost impact of the AD upon U.S. operators of the affected airplanes. The FAA has no way of determining how many airplanes have accomplished the required modification utilizing the 22AWA cable and terminal tags alternative.

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 copy of the final 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, 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) asfollows:

PART 39 - AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 USC 106(g), 40101, 40113, 44701.

Section 39.13 - [AMENDED]
2. Section 39.13 is amended by adding a new airworthiness directive to read as follows: