# AD 90-21-05: Propeller Brake - Type: Airworthiness directive - Status: Current - Products: ATR - GIE Avions de Transport R gional ATR42-300 and ATR42-320 - Effective: October 30, 1990 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Large airplane - Amendment: 39-6757 - Docket: 90-NM-68-AD - Registered aircraft: 20 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/D3E47ABFB1A90BFE86256982006FEE0C.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/90-21-05 ## The airworthiness directive 90-21-05 AEROSPATIALE: Amendment 39-6757. Docket No. 90-NM-68-AD. Applicability: All Model ATR42-300 and ATR42-320 series airplanes, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent the propeller brake from overheating and causing damage to the engine, accomplish the following: A. Within 100 hours time-in-service after May 29, 1989 (the effective date of AD 88- 14-06 R1) for airplanes listed in Aerospatiale Service Bulletin ATR42-61-0013, Revision 1, dated December 8, 1987, modify the propeller brake electronic control wiring, in accordance with this service bulletin. B. Within 100 hours time-in-service after May 29, 1989 (the effective date of AD 88- 14-06 R1), for the airplanes listed in Aerospatiale Service Bulletin ATR42-61-0014, Revision 2, dated November 15, 1988, modify the propeller brake control unit, in accordance with this service bulletin. C. Within 100 hours time-in-service after May 29, 1989 (the effective date of AD 88- 14-06 R1), for the airplanes listed in Aerospatiale Service Bulletin ATR42-61-0010, Revision 3, dated December 19, 1988, replace the pushbutton switch with a two-position mechanical switch, in accordance with this service bulletin. D. Within 180 days after the effective date of this AD, install a new brake control unit in accordance with Aerospatiale Service Bulletin ATR42-61-0005, Revision 2, dated January 2, 1990; Revision 3, dated March 15, 1990; or Revision 4, dated June 19, 1990. E. Within 180 days after the effective date of this AD, install a modified propeller brake in accordance with Aerospatiale Service Bulletin ATR42-61-0022, Revision 1, dated September 25, 1989, or Revision 2, dated March 15, 1990. F. Within 180 days after the effective date of this AD, modify the propeller brake indicating logic, in accordance with Aerospatiale Service Bulletin ATR42-61-0023, Revision 1, dated December 1, 1989; or Revision 2, dated March 15, 1990. G. As an alternative to paragraphs A. through F. of this AD, operators may remove the propeller brake from the airplane in accordance with Aerospatiale Service Bulletin ATR42-61- 0016, Revision 1, dated September 1, 1988. H. 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, Transport Airplane Directorate. NOTE: The request should be submitted directly to the Manager, Standardization Branch, ANM-113, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Manager, Standardization Branch, ANM-113. I. 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 Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, France. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington. Airworthiness Directive 90-21-05 supersedes AD 88-14-06 (Amendment 39-5967) as revised by AD 88-14-06 R1 (Amendment 39-6202). This amendment (39-6757, AD 90-21-05) becomes effective on October 30, 1990. ## 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 2 of 11 models: ATR42-300, ATR42-320 ## 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: 20 (20 by airframe model, 0 by engine model) - Makers: Aerospatiale/Aeritalia 16, Aerospatiale/Alenia 2, Atr-Gie Avions De Transport 1, Atr-Gie Avions De Trnsp Rgnl 1 Models with the most aircraft: - [Aerospatiale/Aeritalia ATR 42-300](https://openairdocs.org/model/aerospatiale-aeritalia-atr-42-300): 12 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) All 5 models: https://openairdocs.org/ad/90-21-05/models.md Every aircraft: https://openairdocs.org/ad/90-21-05/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.