# AD 70-04-01: Blades

- Type: Airworthiness directive
- Status: Current
- Products: McCauley Propeller Systems 2D34C, 2D36C14 and B2D34C
- Effective: February 20, 1970
- Superseded by: Nothing supersedes this AD
- Product type: Propeller
- Amendment: 39-939
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/9C06B468A9C89DED86256965006DB61F.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/70-04-01

## The airworthiness directive

70-04-01 MCCAULEY PROPELLERS: Amdt. 39-939. Applies to 2D36C14- (X)/78KM, 2D34C53-(X)/74E, and B2D34C53-(X)/74E propellers on Lycoming O-360 type engines.

Compliance required within the next 25 hours time in service after the effective date of this AD, unless already accomplished.

To prevent propeller mid-blade and tip failures accomplish the following:

a. Visually inspect blades for foreign object damage or cracks.

b. If blade is damaged, repair in accordance with instructions in McCauley Service Bulletin No. 76 dated 28 November 1969, or an equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. Replace any cracked blades before further flight with a new blade which has been inspected and repaired if necessary in accordance with this AD.

c. Install the following placard near the tachometer:

"Avoid continuous operation, while descending, between 2250 and 2550 r.p.m. with manifold pressure settings below 15 inches mercury".

This amendment is effective February 20, 1970.

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS P7EA](https://openairdocs.org/tcds/P7EA): McCauley Propeller Systems; names 2 of 4 models: 2D34C, B2D34C
- [TCDS P-901](https://openairdocs.org/tcds/P-901): McCauley Propeller Systems; names 1 of 2 models: 2D36C14

## Registered aircraft it may apply to (OpenAirDocs)

No registered aircraft matched the models it names.

Its text cites no advisory circulars or STCs.

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