AD 97-26-10

This amendment adopts a new airworthiness directive (AD), applicable to certain Raytheon Model Hawker 1000 series airplanes, that requires modifying the aft core cowl nozzles of the engine nacelles. This amendment is prompted by a report indicating that the sealant on the core cowl nozzles may extend higher than the forward flange of the core cowl nozzles, which could result in contact between the cowl sealant surface and the lever of the engine mechanical over- speed control system. The actions specified by this AD are intended to prevent such contact, which could cause the over-speed system to function improperly and consequent engine structural failure.

Final rule.

97-26-10 RAYTHEON AIRCRAFT COMPANY (Formerly Raytheon Aircraft Corporation; Beech Aircraft Corporation; Raytheon Corporate Jets, Inc.; British Aerospace, PLC; deHavilland; Hawker Siddeley): Amendment 39-10253. Docket 97-NM-140-AD.

Applicability: Model Hawker 1000 series airplanes; serial numbers 258151, 258159, and 259003 through 259052 inclusive; certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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 (b) 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 contact between the cowl sealant surface and the lever of the engine mechanical over-speed control system, which could cause the over-speed system to function improperly and consequent engine structural failure; accomplish the following:

(a) Within 150 flight hours or 3 months after the effective date of this AD, whichever occurs first, modify the aft core cowl nozzles of the left- and right-hand engine nacelles in accordance with Raytheon Service Bulletin SB.71-48-25F021B, dated May 20, 1997.

NOTE 2: The Raytheon service bulletin references Nordam Hawker 1000 Service Bulletin PW300 71-9, dated April 29, 1995, as the appropriate source of service information for accomplishment of the modification.

(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, Wichita Aircraft Certification Office (ACO), FAA, Small 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, Wichita ACO.

NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Wichita ACO.

(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) The modification shall be done in accordance with Raytheon Service Bulletin SB.71-48-25F021B, dated May 20, 1997. 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 Raytheon Aircraft Company, Manager, Service Engineering, Hawker Customer Support Department, P.O. Box 85, Wichita, Kansas 67201-0085. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Small Airplane Directorate, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(e) This amendment becomes effective on January 23, 1998.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain Raytheon Model Hawker 1000 series airplanes was published in the Federal Register on October 1, 1997 (62 FR 51385). That action proposed to require modifying the aft core cowl nozzles of the engine nacelles.

Comments
Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were submitted in response to the proposal.

Change to Cost Impact Information
The FAA has determined that 48 airplanes, rather than 14 airplanes (as stated in the cost impact paragraph of the proposal), will be affected by this AD. The FAA has revised the cost impact information, below, to reflect this change.
Conclusion
After careful review of the available data, 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 significantly increase the economic burden on any operator nor increase the scope of the AD.

Cost Impact
There are approximately 52 Model Hawker 1000 series airplanes of the affected design in the worldwide fleet. The FAA estimates that 48 airplanes of U.S. registry will be affected by this AD, that it will take approximately 4 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will be provided by the manufacturer at no cost to operators. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $11,520, or $240 per airplane.

The 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 operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact
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, 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) as follows:

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

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