# AD 81-21-01: Erc Cargo Hook Assemblies

- Type: Airworthiness directive
- Status: Current
- Products: Airbus Helicopters SA.315B Alouette III
- Effective: November 4, 1981
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-4227
- Registered aircraft: 4 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0410F87650A1AC0586256A4E004AD8ED.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/81-21-01

## The airworthiness directive

81-21-01 SOCIETE NATIONALE INDUSTRIELLE AEROSPATIALE (SNIAS): Amendment 39-4227. Applies to Model SA315B helicopters, equipped with Eastern Rotorcraft Corporation (ERC) cargo hook assemblies, P/N 17112-4, Serial Numbers 1 through 103, in accordance with Supplemental Type Certificate (STC) SH1735SW, certificated in all categories (Airworthiness Docket No. 81-ASW-33).

Compliance required as indicated.

To prevent possible failure of the ERC cargo hook support legs, P/N 12579-1, due to fatigue cracks, accomplish the following, unless already accomplished, within the next 100 hours' time in service after the effective date of this AD:

a. For suspension assemblies, P/N 17112-4, which have accumulated 1,000 lifts or calendar months of service, whichever occurs first, accomplish a magnetic particle inspection of the lugs, P/N 12579-1, in accordance with Aerospatiale Helicopter Corporation Service Bulletin No. SB315-05, dated March 11, 1981, or an FAA-approved equivalent.b. If one lug is found to have cracks, remove and replace all four lugs in accordance with Aerospatiale Helicopter Corporation Service Bulletin No. SB315-04, dated January 20, 1981, or an FAA-approved equivalent.

c. If no lugs are cracked, reinstall and accomplish magnetic particle inspections at intervals of 1,000 lifts or 12 calendar months, whichever occurs first, as required by paragraph a. of this AD.

d. The inspections required by paragraph a. of this AD are not required after compliance with Aerospatiale Helicopter Corporation Service Bulletin No. SB315-04.

e. The helicopter may be flown in accordance with FAR 21.197 to a base where inspections can be performed.

f. For the purpose of complying with this AD, subject to acceptance by the assigned FAA maintenance inspector, the number of lifts may be determined by multiplying each helicopter's hours' time in service by the operator's fleet average lifts per hour for the helicopter type.

This amendment becomes effective November 4, 1981.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS H1IN](https://openairdocs.org/tcds/H1IN): Airbus Helicopters; names 1 of 5 models: SA.315B Alouette III

## 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: 4 (4 by airframe model, 0 by engine model)
- Makers: Aerospatiale 4

Models with the most aircraft:

- [Aerospatiale SA315B ALOUETTE III](https://openairdocs.org/model/aerospatiale-sa315b-alouette-iii): 4 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/81-21-01/models.md
Every aircraft: https://openairdocs.org/ad/81-21-01/aircraft.md

## Related documents

- [STC SH1735SW-D](https://openairdocs.org/stc/SH1735SW-D): Installation of Eastern Rotorcraft Cargo Hook and H-Frame.. American Eurocopter Corporation, Named in the applicability

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