71-06-03 PRATT & WHITNEY: Amdt. 39-1168 as amended by Amendment 39-1211. Applies to all Pratt & Whitney Aircraft JT4A series turbojet engines which incorporate the following serial number 12th stage compressor rotor disc part number 360112.
2G5181
2G6360
2G5182
2G6362
2G5183
2G6363
2G5446
2G6445
2G5807
2G6448
2G5812
2G6449
2G5818
2G6454
2G5820
2G6581
2G5821
2G6583
2G5825
2G6585
2G5826
3G0201
2G6027
2G6030
5F7645 7
5F858
6F8362
5F7646
5F8588
6F9707
5F8544 through
5F8695
6F9739
5F8547
6F7206
6F9751
5F8550 through
6F7207
6F9753 through
5F8553
6F7210
6F9759
5F8558
6F7214
6F9760 through
5F8576
6F7218
6F9765
5F8577
6F7501
6F9846
5F8581 through
6F7502
6F9853
5F8584
6F7504
6F9861
6F7949
6F9866
6F8168
7F0156
6F8198
7F0480
7F0556
Pratt & Whitney Aircraft telegram PSE/RS/1-3-10-1 covers this same subject.
Compliance required as indicated.
To preclude twelfth stage compressor rotor disc failure as the result of suspected material deficiency, accomplish the following:
1. For all the previously listed serial number twelfth stage compressor rotor discs:
A. With 18,000 hours or more in service within the next 50 hours in service after the effective date of this AD, replace the suspect serial number disc.
B. With 18,000 hours or less in service prior to the accumulation of 18,050 hours in service, replace the suspect serial number disc.
2. Upon submission of substantiating data by an owner or operator through an FAA Maintenance Inspector, the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region, may adjust the compliance time.
Amendment 39-1168 was effective March 12, 1971.
This amendment 39-1211 is effective May 19, 1971 and was effective for all recipients of the telegram dated March 12, 1971 which contained this amendment.