| AD Number | 75-04-07 | Status | Active |
| Effective Date | February 19, 1975 | Issue Date | Not specified |
| Docket Number | Unknown | Amendment | 39-2084 |
| Product Type | ["Engine"] | Product Subtype | Not specified |
| CFR Part | --- - Part 39 | CFR Section | N/A |
| Citation | This information is not available. | ||
| Manufacturer(s) | Pratt & Whitney Division |
| Model(s) | JT3D-3 JT3D-3B JT3D-7 |
75-04-07 PRATT & WHITNEY AIRCRAFT: Amendment 39-2084. Applies to all Pratt & Whitney Aircraft JT3D-3, JT3D-3B, and JT3D-7 turbofan engines containing tenth stage compressor disk, P/N 701810.
Compliance required as indicated.
To ensure adequate life limit margin for tenth stage compressor disk, P/N 701810, the cyclic life limits on these disks have been reduced below the figures currently approved. Unless already accomplished, remove from service the tenth stage compressor disk prior to exceeding the revised life limit listed below or within the next 25 cycles in service after the effective date of this AD, whichever comes later.
Engine Model
Previous Life Limit (Cycles)
Revised Life Limit (Cycles)
JT3D-3
30,000
25,000
JT3D-3B
30,000
25,000
JT3D-7
25,000
23,000
If a disk has been used in more than one engine model, the disk is limited to the lowest cyclic life permitted for the engine models in which it has been exposed.
This amendment becomes effective February 19, 1975.