# AD 74-25-02: Electrical Attitude And Directional Gyros

- Type: Airworthiness directive
- Status: Current
- Products: Aerostar PA-60-600 (Aerostar 600), PA-60-601 (Aerostar 601) and PA-60-601P (Aerostar 601P) with STC SA2336WE or SA2367WE
- Effective: December 4, 1974
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-2029
- Registered aircraft: 9 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/44479BBA649802378625699900514044.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/74-25-02

## The airworthiness directive

74-25-02 TED R. SMITH & ASSOCIATES, INC.: Amendment 39-2029. Applies to Aerostar Models 600/601/601P airplanes certificated in all categories with electrical attitude and directional gyros and 70 amp alternators installed either by the manufacturer or by incorporating STC SA2336WE or STC SA2367WE, as provided below.

Compliance required within the next 30 days after the effective date of this AD, unless already accomplished.

To prevent the possible overloading of the remaining alternator system after failure of either one of the dual alternator systems, accomplish the following:

  (1) Amend, in pertinent part, the Electrical System Load Limitations Section of the FAA-approved Airplane Flight Manual for those airplanes affected, as follows:

"Electrical System Load Limitations

Aircraft with electrical attitude and directional gyros installed and equipped with 70 amp alternators: Do not exceed 55 amps continuous electrical load during IFR conditions.

NOTE.To determine actual alternator load, total the left and right amp readings. Do not read main position for actual alternator load."

  (2) Install a placard in the cockpit, and add to the placard list in the AFM Limitations Section which provides: "Do not exceed 55 amps continuous electrical load during IFR conditions."

  (3) This airworthiness directive must remain with the Airplane Flight Manual until replaced by an FAA-approved AFM revision issued by Ted R. Smith & Associates, Inc. providing the limitations of this A.D.

  (4) The limitations described in (1), above, and placard installed per (2), above, may be removed upon the installation of an alternate electrical warning system approved by the Chief, Aircraft Engineering Division, FAA Western Region.

This amendment becomes effective December 4, 1974.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A17WE](https://openairdocs.org/tcds/A17WE): Aerostar Aircraft Corporation; names 3 of 5 models: PA-60-601P (Aerostar 601P), PA-60-601 (Aerostar 601), PA-60-600 (Aerostar 600)

## 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: 9 (9 by airframe model, 0 by engine model)
- Makers: Piper 9

Models with the most aircraft:

- [Piper PA-60-601P](https://openairdocs.org/model/piper-pa-60-601p): 9 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/74-25-02/models.md
Every aircraft: https://openairdocs.org/ad/74-25-02/aircraft.md

## Related documents

- [STC SA2336WE](https://openairdocs.org/stc/SA2336WE): Installation of Prestolite 70 amp alternators (Avco Lycoming P/N78314) in lieu of existing 50 amp alternators.. Aerostar Aircraft Corporation, Named in the applicability
- [STC SA2367WE](https://openairdocs.org/stc/SA2367WE): Installaton of Prestolite 70 amp alternators (Avco Lycoming P/N78314).. Aerostar Aircraft Corporation, Named in the applicability

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