# AD 89-10-08: Navigation Equipment - Type: Airworthiness directive - Status: Current - Products: ATR - GIE Avions de Transport R gional ATR42-200, ATR42-300, ATR42-320 and ATR42-500 - Effective: June 9, 1989 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Large airplane - Amendment: 39-6205 - Registered aircraft: 28 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/4AAF707F82D7910286256982006FE63C.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/89-10-08 ## The airworthiness directive 89-10-08 AEROSPATIALE: Amendment 39-6205. Applicability: Model ATR-42 series airplanes, Serial Numbers 003 through 093, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent improper functioning of Honeywell-Sperry navigation equipment and to prevent incompatible combinations of this equipment, accomplish the following: A. Within 10 days after the effective date of this AD, accomplish the following in accordance with Aerospatiale Service Bulletin ATR42-34-0027, dated April 6, 1988: 1. Inspect Honeywell-Sperry Symbol Generator Units (SGU) for unauthorized mixing of units in accordance with paragraph C.(1) of the service bulletin. Correct any unauthorized mixing of units prior to further flight. 2. Inspect Honeywell-Sperry navigation equipment for unauthorized mixing of Attitude Heading Reference Units (AHRU) and SGU in accordance with paragraphs C.(2) and C.(3) of the service bulletin. For airplanes with unauthorized mixing of AHRU and SGU, prior to further flight, insert the following into the Limitations Section 2 of the Airplane Flight Manual (AFM). This can be accomplished by inserting a copy of this AD into the AFM and into the Flight Crew Operations Manual: "Approach operations are limited to Category 1 or higher weather minima." Operate the airplane in accordance with this limitation until the requirements of paragraph B. of this AD are accomplished, at which time this limitation may be removed from the AFM. B. Within 120 days after the effective date of this AD, accomplish the following: 1. Replace the Digital Air Data Computer (DADC), in accordance with Aerospatiale Service Bulletin ATR42-34-0024, Revision 1, dated August 30, 1988. 2. Replace the Attitude Heading Reference System (AHRS), in accordance with Aerospatiale Service Bulletin ATR42-34-0025, Revision 1, dated August 30, 1988. 3. Replace the Symbol Generator Units (SGU),in accordance with Aerospatiale Service Bulletin ATR42-34-0026, Revision 1, dated August 30, 1988. C. 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 may add any comments and then send it to the Manager, Standardization Branch, ANM-113. D. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of 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 Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, France. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or at the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington. This amendment (39-6205, AD 89-10-08) becomes effective on June 9, 1989. ## Affected data sheets (1) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS A53EU](https://openairdocs.org/tcds/A53EU): ATR – GIE Avions de Transport Régional; names 4 of 11 models: ATR42-300, ATR42-320, ATR42-200, ATR42-500 ## 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: 28 (28 by airframe model, 0 by engine model) - Makers: Aerospatiale/Aeritalia 16, Atr-Gie Avions De Trnsp Region 6, Aerospatiale/Alenia 3, Atr-Gie Avions De Transport 1, Atr-Gie Avions De Trnsp Rgnl 1, Eads/Alenia ATR 1 Models with the most aircraft: - [Aerospatiale/Aeritalia ATR 42-300](https://openairdocs.org/model/aerospatiale-aeritalia-atr-42-300): 12 aircraft (airframe model) - [Atr-Gie Avions De Trnsp Region ATR42-500](https://openairdocs.org/model/atr-gie-avions-de-trnsp-region-atr42-500): 6 aircraft (airframe model) - [Aerospatiale/Aeritalia ATR 42-320](https://openairdocs.org/model/aerospatiale-aeritalia-atr-42-320): 4 aircraft (airframe model) - [Aerospatiale/Alenia ATR 42-320](https://openairdocs.org/model/aerospatiale-alenia-atr-42-320): 2 aircraft (airframe model) - [Atr-Gie Avions De Transport ATR-42-320](https://openairdocs.org/model/atr-gie-avions-de-transport-atr-42-320): 1 aircraft (airframe model) - [Atr-Gie Avions De Trnsp Rgnl ATR 42-300](https://openairdocs.org/model/atr-gie-avions-de-trnsp-rgnl-atr-42-300): 1 aircraft (airframe model) - [Eads/Alenia ATR ATR 42-500](https://openairdocs.org/model/eads-alenia-atr-atr-42-500): 1 aircraft (airframe model) - [Aerospatiale/Alenia ATR42-500](https://openairdocs.org/model/aerospatiale-alenia-atr42-500): 1 aircraft (airframe model) All 8 models: https://openairdocs.org/ad/89-10-08/models.md Every aircraft: https://openairdocs.org/ad/89-10-08/aircraft.md Its text cites no advisory circulars or STCs. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.