AD 92-11-01

92-11-01 MESSERSCHMITT-BOLKOW-BLOHM (MBB): Amendment 39-8250. Docket Number 92-ASW-12.

Applicability: MBB Model BO 105 LS A-3 helicopters, serial numbers (S/N) 2001 through 2037, certificated in any category and equipped with a torque indication hose assembly, part number (P/N) AE707355-1.

Compliance: Required no later than July 31, 1992, unless previously accomplished.

To prevent failure of the torque indication hose assembly during an engine compartment fire, thereby, fueling the fire with engine oil and leading to possible loss of the helicopter, accomplish the following:

(a) Replace the existing torque indication hose, P/N AE707355-1, on each engine with a new fire resistant torque indication hose, P/N AE705145-14, in accordance with Part 2, Accomplishment Instructions of MBB Alert Service Bulletin No. ASB-BO 105 LS-60-4, Revision 1, dated November 15, 1991.

(b) Special flights permits may be issued in accordance with FAR 21.197 and 21.199 to operatethe helicopter to a location where the requirements of this AD can be accomplished.

(c) An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, New York Aircraft Certification Office, FAA, 181 South Franklin Avenue, Room 202, Valley Stream, New York 11581. The request shall be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager of the New York Aircraft Certification Office.

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

(d) The removal and replacement of the torque indication hose shall be done in accordance with Part 2, Accomplishment Instructions of MBB Helicopters Alert Service Bulletin No. ASB-BO 105 LS-60-4, which incorporates the followingpages:

Pages Revision Level Date 1 through 2 Revision 1 November 15, 1991 3 through 5 Original August 30, 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 MBB Helicopter Corporation, 900 Airport Road, P.O. Box 2349, West Chester, Pennsylvania 19380. Copies may be inspected at the FAA, Office of the Assistant Chief Counsel, 4400 Blue Mound Road, Bldg. 3B, Room 158, Fort Worth, Texas; or at the Office of the Federal Register, 1100 L Street N.W., Room 8401, Washington, D.C.

(e) This amendment becomes effective on August 28, 1992.