# AD 73-15-04: Rubber Drive Plate Grommet

- Type: Airworthiness directive
- Status: Current
- Products: Lycoming Engines HIO-360-D1A
- Effective: July 23, 1973
- Superseded by: Nothing supersedes this AD
- Product type: Engine
- Amendment: 39-1689
- Registered aircraft: 431 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/050540D0A45B27768625682A0054E89F.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/73-15-04

## The airworthiness directive

73-15-04 AVCO LYCOMING: Amdt. 39-1689. Applies to HIO-360-D1A model engines installed on Hughes Models 269C and 300C helicopters. Compliance required within 300 hours time in service after the effective date of this AD and every 300 hours in service thereafter. To prevent possible failures of the Bendix part numbers 10-349235-3 and 10-349235-4 magnetos, replace the part number 10-391315 rubber drive plate grommet in accordance with Lycoming Service Bulletin No. 364 or equivalent procedure approved by Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. This amendment is effective July 23, 1973.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 1E10](https://openairdocs.org/tcds/1E10): Lycoming Engines; names 1 of 89 models: HIO-360-D1A

## 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: 431 (0 by airframe model, 431 by engine model)
- Makers: Schweizer 127, Enstrom 115, Hughes 111, Enstrom Helicopter 31, Cessna 3, Schweizer RSG 3, Bellanca 2, Pitts Special 2, Andrews 1, Beech 1

Models with the most aircraft:

- [Lycoming HIO-360 series](https://openairdocs.org/engine/lycoming-hio-360-series): 336 aircraft (engine model)
- [Lycoming HI0-360 series](https://openairdocs.org/engine/lycoming-hi0-360-series): 54 aircraft (engine model)
- [Lycoming HIO-360-D1A](https://openairdocs.org/engine/lycoming-hio-360-d1a): 41 aircraft (engine model)

All 3 models: https://openairdocs.org/ad/73-15-04/models.md
Every aircraft: https://openairdocs.org/ad/73-15-04/aircraft.md

Its text cites no advisory circulars or STCs.

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