90-03-04 GARRETT ENGINE DIVISION, (hereinafter called "GARRETT") ALLIED SIGNAL INCORPORATED: Amendment 39-6419.
Applicability: Models TFE731-3, -3A, -3AR, and -3R turbofan engines equipped with high pressure turbine rotor (HPTR) discs, part numbers 3072316-2, -3, and 3073110-1, -2.
Compliance: Required as indicated, unless already accomplished.
To prevent an uncontained engine failure, accomplish the following:
(a) Remove and replace with a serviceable part, specific serial number HPTR discs, in accordance with the accomplishment instructions in Garrett Alert Service Bulletin TFE731-A72-3388, dated February 28, 1989, at next access to the turbine rotor assembly or within 150 operating cycles after the effective date of this AD or prior to June 1, 1990, whichever occurs first.
NOTES: (1) For the purpose of this AD, access to the turbine rotor assembly is defined as whenever the N1 turbine module is separated from the engine.
(2) Discs inspected by Garrett as noted in Garrett Alert Service Bulletin TFE731-A72- 3388, dated February 28, 1989, and determined to be airworthy may be returned to service.
(b) Aircraft may be ferried in accordance with the provisions of FAR 21.197 and 21.199 to a base where the AD can be accomplished.
(c) Upon submission of substantiating data by an owner or operator through an FAA Airworthiness Inspector, an alternate means of compliance with the requirements of this AD or adjustments to the compliance times specified in this AD may be approved by the Manager, Los Angeles Aircraft Certification Office, Federal Aviation Administration, Transport Airplane Directorate, Aircraft Certification Service, 3229 East Spring Street, Long Beach, California 90806-2425.
This amendment (39-6419, AD 90-03-04) becomes effective on February 22, 1990.