# AD 54-02-01: Magneto Timing

- Type: Airworthiness directive
- Status: Current
- Products: Textron Lycoming, AVCO O-290-D2
- Superseded by: Nothing supersedes this AD
- Product type: Engine
- Registered aircraft: 2,230 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/CADEDEB2835379B38625682700706BB8.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/54-02-01

## The airworthiness directive

54-02-01 LYCOMING: Applies to All Model O-290-D2 Engines. Compliance required by February 1, 1954, and at each subsequent 100-hour inspection. In order to preclude the possibility of serious engine damage from incipient detonation under certain atmospheric and altitude conditions, the magneto timing of all Lycoming O-290-D2 engines must be set at 18 degrees BTC. To insure that the magneto timing does not change substantially from this setting, it should be checked and reset, if necessary, at each subsequent 100-hour inspection. (Lycoming Service Bulletin No. 169 covers this same subject, but recommends that the timing be checked every 50 hours.)

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS E-229](https://openairdocs.org/tcds/E-229): Lycoming Division AVCO Corporation; names 1 of 10 models: O-290-D2

## 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: 2,230 (0 by airframe model, 2,230 by engine model)
- Makers: Piper 1,446, Champion 55, Cessna 17, Stinson 15, Monocoupe 10, Pitts Special 10, Smith Miniplane 10, Thorp 8, Callair 7, Eaa Biplane 7

Models with the most aircraft:

- [Lycoming 0-290 series](https://openairdocs.org/engine/lycoming-0-290-series): 2,126 aircraft (engine model)
- [Lycoming O-290-D2](https://openairdocs.org/engine/lycoming-o-290-d2): 58 aircraft (engine model)
- [Lycoming O-290 series](https://openairdocs.org/engine/lycoming-o-290-series): 46 aircraft (engine model)

All 3 models: https://openairdocs.org/ad/54-02-01/models.md
Every aircraft: https://openairdocs.org/ad/54-02-01/aircraft.md

Its text cites no advisory circulars or STCs.

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