# AD 74-07-02: Aluminum Tail Rotor Blades

- Type: Airworthiness directive
- Status: Current
- Products: MD Helicopters 369A, 369H, 369HE, 369HM and 369HS
- Effective: March 26, 1974
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-1802
- Registered aircraft: 125 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/C10243E96517349C86256A39004AB291.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/74-07-02

## The airworthiness directive

74-07-02 HUGHES: Amendment 39-1802. Applies to Hughes Models 369A, 369H, 369HE, 369HS and 369HM Helicopters certificated in all categories.

"Pursuant to the authority of the Federal Aviation Act of 1958, delegated to me by the Administrator, the following airworthiness directive applicable to operators of Hughes Model 369A, 369H, 369HE, 369HS and 369HM Helicopters, equipped with aluminum tail rotor blade P/N 369A1613-3, certificated in all categories is effective immediately upon receipt of this airmail letter. Before further flight, unless already accomplished, and upon any installation or replacement of aluminum tail rotor blade P/N 369A1613-3, inspect the tail rotor assembly to verify that the rotor blade P/N 369A1613-3 serial numbers 0001 through 0156 are not mated with blade serial numbers 0157 and subsequent. Replace mismatched tail rotor blade(s) before further flight. Note AD inspection in Aircraft Maintenance Records. Forthcoming Service Bulletin, No. HN-65 covers the same subject."

This amendment is effective March 26, 1974 for all persons except those to whom it was made effective by airmail letter, dated February 25, 1974, which contained this amendment.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS H3WE](https://openairdocs.org/tcds/H3WE): MD Helicopters LLC; names 5 of 12 models: 369HS, 369HM, 369HE, 369H, 369A (Army OH-6A)

## 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: 125 (125 by airframe model, 0 by engine model)
- Makers: Hughes 116, MD Helicopters 6, Hughes/Batto John 1, Hughes/Helicopter Assocs 1, Summa 1

Models with the most aircraft:

- [Hughes 369HS](https://openairdocs.org/model/hughes-369hs): 69 aircraft (airframe model)
- [Hughes 369A](https://openairdocs.org/model/hughes-369a): 32 aircraft (airframe model)
- [Hughes 369A (OH-6A)](https://openairdocs.org/model/hughes-369a-oh-6a): 11 aircraft (airframe model)
- [MD Helicopters 369HS](https://openairdocs.org/model/md-helicopters-369hs): 3 aircraft (airframe model)
- [Hughes 369HE](https://openairdocs.org/model/hughes-369he): 3 aircraft (airframe model)
- [MD Helicopters 369HM](https://openairdocs.org/model/md-helicopters-369hm): 2 aircraft (airframe model)
- [Summa 369HS](https://openairdocs.org/model/summa-369hs): 1 aircraft (airframe model)
- [MD Helicopters 369A](https://openairdocs.org/model/md-helicopters-369a): 1 aircraft (airframe model)
- [Hughes/Helicopter Assocs 369A](https://openairdocs.org/model/hughes-helicopter-assocs-369a): 1 aircraft (airframe model)
- [Hughes/Batto John 369A (OH-6A)](https://openairdocs.org/model/hughes-batto-john-369a-oh-6a): 1 aircraft (airframe model)
- [Hughes 369H](https://openairdocs.org/model/hughes-369h): 1 aircraft (airframe model)

All 11 models: https://openairdocs.org/ad/74-07-02/models.md
Every aircraft: https://openairdocs.org/ad/74-07-02/aircraft.md

Its text cites no advisory circulars or STCs.

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