AD 97-13-09 Airworthiness Directives; McDonnell Douglas Helicopter Systems Model MD-900 Helicopters

Models named: MD-900. Read the applicability below — it usually turns on serial or part numbers too.

Model MD-900 helicopters, 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 (d) 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.

Required as indicated, unless accomplished previously. To establish a life limit for various parts and reduce the current life limit on other parts, accomplish the following: (a) Within 100 hours time-in-service (TIS) after the effective date of this AD: (1) For Model MD-900 helicopters with serial number (S/N) 0002 through 0012, apply serial numbers to the mid-forward truss assembly, P/N 900F2401200-102, and the forward and aft deck-fitting assemblies, P/N 900F2401500-103 and P/N 900F2401600-103. (2) For Model MD-900 helicopters with S/N 0002 through 0048, apply S/N's to the left and right vertical stabilizer control system (VSCS) bellcrank assemblies, P/N 900F2341712-101 or P/N 900FP341712- 103, and the mid-aft truss strut assembly, P/N 900F2401300-103. (3) Apply the S/N's as specified in paragraphs (a)(1) and (a)(2) of this AD adjacent to the existing P/N's, and in accordance with the Accomplishment Instructions of McDonnell Douglas Helicopter Systems Service Bulletin No. SB900-039, Revision 2, dated March 12, 1997. (b) Before further flight, remove from service: (1) The non-rotating swashplate assembly, P/N 900C2010192-105, - 107, -109, or -111, on or before attaining 554 hours TIS. (2) The collective drive link assembly, P/N 900C2010207-101, on or before attaining 1,480 hours TIS. (3) The self-aligning, spherical/slider main rotor bearing, P/N 900C3010042-103, on or before attaining 480 hours TIS. (4) The VSCS bellcrank assembly, P/N 900FP341712-103, and bellcrank arm, P/N 900F2341713-101 (used in the VSCS bellcrank assembly, P/N 900F2341712-101), on or before attaining 2,700 hours TIS. (c) This AD revises the Airworthiness Limitations section of the maintenance manual by establishing new retirement lives for these parts. (d) 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, Los Angeles Aircraft Certification Office. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Los Angeles Aircraft Certification Office. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles Aircraft Certification Office. (e) 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. (f) The modification shall be done in accordance with McDonnell Douglas Helicopter Systems Bulletin No. SB900-039, Revision 2, dated March 12, 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 McDonnell Douglas Helicopter Systems, Technical Publications, Bldg. 530/B11, 5000 E. McDowell Road, Mesa, Arizona 85205-9797. 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. (g) This amendment becomes effective on July 10, 1997. Issued in Fort Worth, Texas, on June 17, 1997. Eric Bries, Acting Manager, Rotorcraft Directorate, Aircraft Certification Service. [FR Doc. 97-16568 Filed 6-24-97; 8:45 am] BILLING CODE 4910-13-U