75-04-07: Tenth Stage Compressor Disk
FAA order 75-04-07 is an airworthiness directive in force since February 19, 1975. The FAA's subject line: Tenth Stage Compressor Disk. It names the Pratt & Whitney JT3D-3B, Pratt & Whitney JT3D series engines: about 5 aircraft on the U.S. register today across them, though an order usually covers particular versions or serial numbers rather than every one. System: engine.
What it applies to as the FAA lists it
- Kind of product
- Engine
- Makes
- Pratt & Whitney Division
- Models
- JT3D-3, JT3D-3B, JT3D-7
- Engine series
- Pratt & Whitney JT3D-3B 3 aircraft
Pratt & Whitney JT3D series 2 aircraft
Dates and paperwork
- In force since
- February 19, 1975
- Docket
- Unknown
- Status
- Current
- The FAA's document
- Read the order on the FAA's site
The order itself the regulatory text, as published
Show the full text (1,011 characters)
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.
Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of October 7, 2026. Connections as data: /graph/directive/75-04-07.json · aircraft systems.