# AD 93-25-14: AC Generator Control Relays

- Type: Airworthiness directive
- Status: Current
- Products: Saab AB, Saab Aerosystems SAAB 340B and 340A (SAAB SF340A)
- Effective: February 14, 1994
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-8778
- Docket: 93-NM-137-AD
- Registered aircraft: 66 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/42148487EC20E95086256A1F005A5A17.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/93-25-14

## The airworthiness directive

93-25-14 SAAB-SCANIA: Amendment 39-8778. Docket 93-NM-137-AD. Applicability: Model SAAB SF340A series airplanes, serial numbers 004 through 159 inclusive; and Model SAAB 340B series airplanes, serial numbers 160 through 325 inclusive; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent loss of AC electrical power, and local area damage that may lead to further electrical failures and smoke in the cockpit, accomplish the following:

  (a) Within 6 months after the effective date of this AD, replace the left- and right-hand AC generator control relays, part number (P/N) SM15CXD1, with new relays, P/N SM15CXD4, at generator control positions 7XA and 8XA, in accordance with SAAB 340 Service Bulletin SAAB 340-24-022, dated October 21, 1992.

  (b) As of the effective date of this AD, no person shall install an AC generator control relay, P/N SM15CXD1, at generator control positions 7XA or 8XA on any airplane.(c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Standardization Branch, ANM-113.

NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113.

  (d) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished.

  (e) The replacement shall be done in accordance with SAAB 340 Service Bulletin SAAB 340- 24-022, dated October 21, 1992. This incorporation by reference was approved by the Director of the Federal Register in accordancewith 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from SAAB-SCANIA AB, SAAB Aircraft Support Product, S-581.88, Linkoping, Sweden. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

  (f) This amendment becomes effective on February 14, 1994.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A52EU](https://openairdocs.org/tcds/A52EU): Saab AB; names 2 of 2 models: 340A (SAAB SF340A), SAAB 340B

## 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: 66 (66 by airframe model, 0 by engine model)
- Makers: Saab-Scania 42, Saab 15, Saab-Fairchild 8, Saabscania 1

Models with the most aircraft:

- [Saab-Scania SAAB 340B](https://openairdocs.org/model/saab-scania-saab-340b): 42 aircraft (airframe model)
- [Saab SAAB 340B](https://openairdocs.org/model/saab-saab-340b): 15 aircraft (airframe model)
- [Saab-Fairchild 340A](https://openairdocs.org/model/saab-fairchild-340a): 8 aircraft (airframe model)
- [Saabscania SAAB 340B](https://openairdocs.org/model/saabscania-saab-340b): 1 aircraft (airframe model)

All 6 models: https://openairdocs.org/ad/93-25-14/models.md
Every aircraft: https://openairdocs.org/ad/93-25-14/aircraft.md

Its text cites no advisory circulars or STCs.

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