AD 94-16-04

This amendment adopts a new airworthiness directive (AD), applicable to Schweizer Aircraft Corporation and Hughes Helicopters, Inc. Model 269A, 269A-1, 269B, 269C, and TH55A series helicopters, that requires a one-time visual inspection to detect missing or damaged tail rotor pedal bulkhead gussets (gussets), loose or missing gusset rivets, and initial installation of missing gussets or replacement of damaged gussets and rivets, if necessary. This amendment is prompted by reports of missing or damaged tail rotor pedal bulkhead gussets and loose or missing gusset rivets. The actions specified by this AD are intended to prevent failure of the tail rotor pedal support structure that could result in loss of tail rotor control and subsequent loss of control of the helicopter.

Final rule

94-16-04 SCHWEIZER AIRCRAFT CORPORATION and HUGHES HELICOPTERS, INC.: Amendment 39-8994. Docket Number 93-SW-05-AD.

Applicability: Model 269A, 269A-1, 269B, 269C, and TH55A series helicopters, certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent failure of the tail rotor pedal support structure that could result in loss of tail rotor control and subsequent loss of control of the helicopter, accomplish the following:

(a) Within 100 hours' time-in-service after the effective date of this AD, conduct a visual inspection of the tail rotor pedal bulkhead gussets (gussets) to detect missing or cracked gussets, elongated rivet holes, and loose or missing rivets, in accordance with Part I of Schweizer Service Bulletin B-247 (SB), dated October 30, 1992.

(1) If the gussets are missing, before further flight, install gussets in accordance with Part II of the SB, dated October 30, 1992.

(2) If the gussetsare cracked or contain elongated rivet holes, before further flight, install replacement gussets in accordance with Part III of the SB, dated October 30, 1992.

(3) If the gussets contain loose or missing rivets, before further flight, install new (zero time) rivets in accordance with Part III of the SB, dated October 30, 1992.

(b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used when approved by the Manager, New York Aircraft Certification Office, FAA. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, New York Aircraft Certification Office.

NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the New York Aircraft Certification Office.

(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 helicopter to a location where the requirements of this AD can be accomplished.

(d) The inspection and replacement, if necessary, shall be done in accordance with Schweizer Aircraft Corporation Service Bulletin B-247, dated October 30, 1992. 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 Schweizer Aircraft Corporation, P.O. Box 147, Elmira, New York 14902. Copies may be inspected at the FAA, Office of the Assistant Chief Counsel, 2601 Meacham Blvd., Room 663, Fort Worth, Texas; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(e) This amendment becomes effective on October 5, 1994.

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 Schweizer Aircraft Corporation and Hughes Helicopters, Inc. Model 269A, 269A-1, 269B, 269C, and TH55A series helicopters was published in the Federal Register on May 3, 1993 (58 FR 26264). That action proposed to require, within the next 100 hours' time-in-service after the effective date of this AD, a one-time visual inspection to detect missing or cracked gussets, elongated rivet holes, and loose or missing rivets. Also proposed, before further flight, was the initial installation of any missing gussets or replacement of cracked gussets, gussets with elongated rivet holes, or gussets that contain loose or missing rivets.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposal or the FAA's determination of the costto the public. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed with only editorial changes. The FAA has determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

The FAA estimates that 934 helicopters of U.S. registry will be affected by this AD, that it will take approximately 2 work hours per helicopter to accomplish the required actions, and that the average labor rate is $55 per work hour. Required parts will cost approximately $80 per helicopter. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $177,460.

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, itis 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. 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 a new airworthiness directive to read as follows: