AD 95-11-14

This amendment adopts a new airworthiness directive (AD), applicable to Bell Helicopter Textron, Inc. Model 206A, 206B, 206L, 206L-1, 206L-3, and 206L-4 helicopters, that requires removal and replacement of certain crosstube assemblies (crosstubes). This amendment is prompted by two accidents attributed to crosstube failures and 27 field reports that indicated corrosion or metal fatigue may cause a failure of the affected crosstubes. The actions specified by this AD are intended to prevent failure of the crosstubes and subsequent loss of control of the helicopter.

Final rule

95-11-14 BELL HELICOPTER TEXTRON, INC (BHTI): Amendment 39-9247. Docket No. 94-SW-08-AD.

Applicability: Model 206A, 206B, 206L, 206L-1, 206L-3, and 206L-4 helicopters, with crosstube assemblies (crosstubes), BHTI part numbers (P/N) 206-050-107, 206-050-119, 206-050-134, 206-050-157, 206-050-169, 206-053-109, 206-053-119, and 206-053-129 (all dash numbers), or Airborne Supply, Inc. P/N AB206-050-107, AB206-050-119, or AB206-053-109 (all dash numbers), installed, certificated in any category.

NOTE 1: This AD applies to each helicopter 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 helicopters 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 (c) 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 helicopter from the applicability of this AD.

Compliance: Required as indicated, unless accomplished previously.

To prevent failure of the crosstubes and subsequent loss of control of the helicopter, accomplish the following:

(a) Within 90 calendar days after the effective date of this AD, remove any affected crosstube and replace it with an airworthy crosstube in accordance with the appropriate maintenance manual or service instructions. Any crosstubes removed as a result of this AD shall be permanently marked as unairworthy.

NOTE 2: For BHTI P/N 206-053-109 and 206-053-119, the P/N are vibro-etched onthe upper cuff of the crosstube on the aft side on both forward and aft crosstubes; for BHTI P/N 206- 053-129, the P/N is vibro-etched on the bottom of the cuff on the aft side on both forward and aft crosstubes; for BHTI P/N 206-050-107, 206-050-119, 206-050-134, 206-050-157, and 206-050- 169, the P/N are stamped in ink on the crosstube, which is shipped without paint (once the helicopter is painted, the P/N are covered); and for Airborne Supply, Inc., P/N AB206-050-107, AB206-050-119, and AB206-053-109, the P/N are rubber stamped at the bottom end of the crosstube.

(b) If the crosstubes' P/N cannot be determined by reference to the crosstubes, if possible, determine the P/N by reference to the maintenance records or other aircraft records. If the crosstubes' P/N cannot be determined, replace the crosstubes with airworthy crosstubes within 90 calendar days after the effective date of this AD in accordance with the appropriate maintenance manual or service instructions.

(c)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, Rotorcraft Certification Office, FAA, Rotorcraft Directorate. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Rotorcraft Certification Office.

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

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

(e) This amendment becomes effective on June 30, 1995.

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 Bell Helicopter Textron, Inc. Model 206A, 206B, 206L, 206L-1, 206L-3, and 206L-4 helicopters was published in the Federal Register on November 14, 1994 (59 FR 56438). That action proposed to require removal and replacement of certain crosstubes within the next 90 calendar days.

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the one comment received.

The commenter states that the FAA should require an annual skid gear inspection rather than requiring the more costly replacement of the crosstubes. The FAA does not concur. The FAA has determined that, due to the location of the potential crack and the speed at which a crack could propagate, an annual inspection would not be a sufficient interval to detecta potentially critical crack. The economic impact of a repetitive inspection at an interval short enough to detect the crack would have a greater adverse economic impact on owners/operators than the economic impact which would be incurred by replacing the crosstubes.

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 as proposed, except for editorial changes and adding explanatory Note 1, relating to the scope of the applicability statement when modifications, alterations, or repairs have been made in the area subject to the requirements of the AD.

The FAA estimates that 5,700 helicopters of U.S. registry will be affected by this AD, that it will take approximately 10 work hours per helicopter to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will cost approximately $6,400 per helicopter. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $39,900,000 to replace two crosstubes per helicopter.

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, 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: