# AD 90-02-15: Auxiliary Power Unit

- Type: Airworthiness directive
- Status: Current
- Products: Airbus A320-111, A320-211, A320-212, A320-214, A320-231, A320-232 and A320-233
- Effective: February 20, 1990
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-6477
- Registered aircraft: 563 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/42833EA56399B3F98625695A00706D16.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/90-02-15

## The airworthiness directive

90-02-15 AIRBUS INDUSTRIE: Amendment 39-6477.

Applicability: Model A320 series airplanes, Serial Numbers 005 through 039, and 042 through 049, certificated in any category.

Compliance: Required within 60 days after the effective date of this AD, unless previously accomplished.

To prevent possible false electronic centralized aircraft monitor (ECAM) messages on Auxiliary Power Unit (APU) shutdown, accomplish the following:

A. Replace the standby transformer/rectifier (TR) with one identical to the main TR, and relocate it to a position with improved ventilation, in accordance with Airbus Industrie Service Bulletin No. A320-24-1028, dated July 7, 1989.

B. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Northwest Mountain Region.

NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment and then send it to the Manager, Standardization Branch, ANM-113.

C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.

All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Airbus Industrie, Airbus Support Division, Avenue Didier Daurat, 31700 Blagnac, France. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or the Standardization Branch, 9010 East Marginal Way South, Seattle, Washington.

This amendment (39-6477, AD 90-02-15) becomes effective on February 20, 1990.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A28NM](https://openairdocs.org/tcds/A28NM): Airbus SAS; names 7 of 50 models: A320-111, A320-211, A320-212, A320-214, A320-231, A320-232, A320-233

## 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: 563 (563 by airframe model, 0 by engine model)
- Makers: Airbus 377, Airbus Industrie 184, Airbus S A S 2

Models with the most aircraft:

- [Airbus A320-232](https://openairdocs.org/model/airbus-a320-232): 189 aircraft (airframe model)
- [Airbus A320-214](https://openairdocs.org/model/airbus-a320-214): 160 aircraft (airframe model)
- [Airbus Industrie A320-232](https://openairdocs.org/model/airbus-industrie-a320-232): 109 aircraft (airframe model)
- [Airbus Industrie A320-212](https://openairdocs.org/model/airbus-industrie-a320-212): 39 aircraft (airframe model)
- [Airbus Industrie A320-214](https://openairdocs.org/model/airbus-industrie-a320-214): 26 aircraft (airframe model)
- [Airbus A320-233](https://openairdocs.org/model/airbus-a320-233): 21 aircraft (airframe model)
- [Airbus Industrie A320-211](https://openairdocs.org/model/airbus-industrie-a320-211): 6 aircraft (airframe model)
- [Airbus A320-211](https://openairdocs.org/model/airbus-a320-211): 3 aircraft (airframe model)
- [Airbus Industrie A320-231](https://openairdocs.org/model/airbus-industrie-a320-231): 2 aircraft (airframe model)
- [Airbus A320-212](https://openairdocs.org/model/airbus-a320-212): 2 aircraft (airframe model)
- [Airbus S A S A320-214](https://openairdocs.org/model/airbus-s-a-s-a320-214): 2 aircraft (airframe model)
- [Airbus A320-231](https://openairdocs.org/model/airbus-a320-231): 2 aircraft (airframe model)
- [Airbus Industrie A320-233](https://openairdocs.org/model/airbus-industrie-a320-233): 1 aircraft (airframe model)
- [Airbus Industrie A320-111](https://openairdocs.org/model/airbus-industrie-a320-111): 1 aircraft (airframe model)

All 15 models: https://openairdocs.org/ad/90-02-15/models.md
Every aircraft: https://openairdocs.org/ad/90-02-15/aircraft.md

Its text cites no advisory circulars or STCs.

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