# AD 75-07-06: Second Stage Turbine Blades

- Type: Airworthiness directive
- Status: Current
- Products: Rolls-Royce 501-D22A
- Effective: April 7, 1975
- Superseded by: Nothing supersedes this AD
- Product type: Engine
- Amendment: 39-2141
- Registered aircraft: 12 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/434158E66E8430D086256854006E3AD2.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/75-07-06

## The airworthiness directive

75-07-06 DETROIT DIESEL ALLISON: Amendment 39-2141. Applies to Detroit Diesel Allison Model 501-D22A engines with turbine assemblies having the following serial numbers:

750137, 750138, 750139, 750140, 750142, 750143, 750145, 750146A, 750147A, 750149, 750150, 750151, 750154, 750158, 750160, 750166, 750176, 750177, 750179, 750181, 750182A, 750184, 750194, 750195, 750201A, 750204, 750205, 750208, 750212, 750213, 750214, 750229, 750230, 750231, 750235, 750241A, 750263A, 750266, 750272, 750301, 750305, 750309, 750312

Within the next 300 hours' time in service after the effective date of this Airworthiness Directive, unless already accomplished, remove the part number 6852228 second stage turbine blades and replace with part number 6890508 second stage turbine blades. Detroit Diesel Allison Commercial Overhaul Information Letter Number COIL-1019 pertains to this subject.

This amendment is effective April 7, 1975.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS E-282](https://openairdocs.org/tcds/E-282): Rolls-Royce Corporation; names 1 of 9 models: 501-D22A

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 12 (0 by airframe model, 12 by engine model)
- Makers: Lockheed 12

Models with the most aircraft:

- [Allison 501-D22A](https://openairdocs.org/engine/allison-501-d22a): 12 aircraft (engine model)

All 1 models: https://openairdocs.org/ad/75-07-06/models.md
Every aircraft: https://openairdocs.org/ad/75-07-06/aircraft.md

Its text cites no advisory circulars or STCs.

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