# AD 91-10-01: Traffic Alert and Collision Avoidance Systems - Type: Airworthiness directive - Status: Current - Products: ATR - GIE Avions de Transport Régional ATR42-200, ATR42-300, 727-100 Series, 727-100C Series, 727-200 Series, 727-200F Series, 727 Series, 727C Series, 747-100 Series, 747-100B Series, 747-100B SUD Series, 747-200B Series and 19 more - Effective: March 10, 1992 - Superseded by: Nothing supersedes this AD - Product type: Appliance - Amendment: 39-8002 - Docket: 91-CE-42-AD - Registered aircraft: 249 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/5FD00B7CD1D4896386256A41006CC988.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/91-10-01 ## The airworthiness directive 91-10-01 COLLINS: Amendment 39-8002. Docket No. 91-CE-42-AD. Applicability: All aircraft equipped with the Traffic Alert and Collision Avoidance (TCAS) II (or 94) systems that are installed in, but not limited to, the following aircraft, certificated in any category: Boeing 727, 727C, 727-100/100C/200/200F airplanes; Boeing 747-100, 200, SR, SP airplanes; McDonnell Douglas DC9-81/82/83/87 and MD-88 airplanes; Aerospatialle ATR42-200/300 airplanes; Lockheed L1011-385-1 airplanes; DeHavilland DHC-7 airplanes; Saab SF340A/B airplanes; and Shorts Brothers SD3-60 airplanes. Compliance: Required as indicated, unless already accomplished. To prevent altitude deviations, which could result in unnecessary pilot/controller communication and controller distraction, accomplish the following: (a) Within the next 25 hours time-in-service (TIS) after the effective date of this AD, unless already accomplished (priority letter AD 91-10-01), accomplish the following: (1) Pull and band the circuit breaker that applies electrical power to the TCAS II (or 94) system. (2) Fabricate a placard with the following words in 1/8 inch high letters: "TCAS II Inoperative" or "TCAS 94 Inoperative" as appropriate. Install this placard adjacent to the TCAS control unit within the pilot's clear view and operate the aircraft accordingly. (b) Reactivation of the TCAS II (or 94) system must be accomplished after modification of the Collins TTR-920 Computer in accordance with Collins Service Bulletin (SB) C, dated April 24, 1991, or No. 7, dated April 4, 1991, whichever is applicable, or Collins SB C, Revision 1, or SB No. 7, Revision 1, both dated May 20, 1991, whichever is applicable. This reactivation must be accomplished in accordance with a schedule acceptable to the administrator. (c) Within the next 30 days after the effective date of this AD, unless already accomplished (priority letter AD 91-10-01), the airlines operating the aircraft affectedby this AD must submit to the FAA for approval, a schedule for reactivation of the TCAS II (or 94) system. (d) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate aircraft to a location where the requirements of this AD can be accomplished. (e) An alternative method of compliance or adjustment of the compliance times that provides an equivalent level of safety may be approved by the Manager, Wichita Aircraft Certification Office, FAA, 1801 Airport Road, Mid-Continent Airport, Wichita, Kansas 67209. The request should be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Wichita Aircraft Certification Office. (f) The modification required by this AD shall be done in accordance with Collins Service Bulletin (SB) C, dated April 24, 1991, or Collins SB No. 7, dated April 4, 1991, whichever is applicable; or whichever of the following two revised service bulletins that is applicable: SB C, Revision 1, which incorporates the following pages: Pages Issue Level Date 4 and 5 Revision 1 May 20, 1991 1, 2, 3 and 6 Original April 24, 1991 or Collins SB No. 7, Revision 1, which incorporates the following pages: Pages Issue Level Date 1, 4 and 8 Revision 1 May 20, 1991 2, 3, 5, 6, 7, and 9 through 34 Original April 4, 1991 This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Rockwell International, Avionics Group, 400 Collins Road, NE; Cedar Rapids, Iowa 52498. Copies may be inspected at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 1100 L Street, NW, Room 8401, Washington, DC. (g) This amendment (39-8002) supersedes Priority Letter AD 91-10-01. (h) This amendment (39-8002, AD 91-10-01) becomes effective on March 10, 1992. ## Affected data sheets (7) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS A20WE](https://openairdocs.org/tcds/A20WE): The Boeing Company; names 8 of 14 models: 747-100B Series, 747SP Series, 747-200B Series, 747-200F Series, 747-200C Series, 747-100B SUD Series, 747SR Series, 747-100 Series - [TCDS A3WE](https://openairdocs.org/tcds/A3WE): The Boeing Company; names 6 of 6 models: 727-100 Series, 727 Series, 727-200 Series, 727-100C Series, 727-200F Series, 727C Series - [TCDS A20EA](https://openairdocs.org/tcds/A20EA): De Havilland Aircraft of Canada Limited; names 5 of 5 models: DHC-7-101, DHC-7-103, DHC-7-102, DHC-7-100, DHC-7-1 - [TCDS A6WE](https://openairdocs.org/tcds/A6WE): The Boeing Company; names 5 of 25 models: MD-88, DC-9-81 (MD-81), DC-9-83 (MD-83), DC-9-87 (MD-87), DC-9-82 (MD-82) - [TCDS A52EU](https://openairdocs.org/tcds/A52EU): Saab AB; names 2 of 2 models: 340A (SAAB SF340A), SAAB 340B - [TCDS A53EU](https://openairdocs.org/tcds/A53EU): ATR – GIE Avions de Transport Régional; names 2 of 11 models: ATR42-300, ATR42-200 - [TCDS A23WE](https://openairdocs.org/tcds/A23WE): Lockheed Martin Corporation; names 1 of 4 models: L-1011-385-1 ## 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: 249 (249 by airframe model, 0 by engine model) - Makers: Mcdonnell Douglas 99, Saab-Scania 42, Boeing 35, Short Bros 26, Saab 15, Aerospatiale/Aeritalia 12, Saab-Fairchild 8, Dehavilland 7, Lockheed 2, Atr-Gie Avions De Trnsp Rgnl 1 Models with the most aircraft: - [Mcdonnell Douglas DC-9-83(MD-83)](https://openairdocs.org/model/mcdonnell-douglas-dc-9-83-md-83): 49 aircraft (airframe model) - [Saab-Scania SAAB 340B](https://openairdocs.org/model/saab-scania-saab-340b): 42 aircraft (airframe model) - [Short Bros SD3-60](https://openairdocs.org/model/short-bros-sd3-60): 26 aircraft (airframe model) - [Mcdonnell Douglas DC-9-82(MD-82)](https://openairdocs.org/model/mcdonnell-douglas-dc-9-82-md-82): 22 aircraft (airframe model) - [Saab SAAB 340B](https://openairdocs.org/model/saab-saab-340b): 15 aircraft (airframe model) - [Mcdonnell Douglas MD-88](https://openairdocs.org/model/mcdonnell-douglas-md-88): 14 aircraft (airframe model) - [Mcdonnell Douglas DC-9-87](https://openairdocs.org/model/mcdonnell-douglas-dc-9-87): 13 aircraft (airframe model) - [Aerospatiale/Aeritalia ATR 42-300](https://openairdocs.org/model/aerospatiale-aeritalia-atr-42-300): 12 aircraft (airframe model) - [Boeing 727-223](https://openairdocs.org/model/boeing-727-223): 9 aircraft (airframe model) - [Saab-Fairchild 340A](https://openairdocs.org/model/saab-fairchild-340a): 8 aircraft (airframe model) - [Dehavilland DHC-7-102](https://openairdocs.org/model/dehavilland-dhc-7-102): 5 aircraft (airframe model) - [Boeing 727-227](https://openairdocs.org/model/boeing-727-227): 4 aircraft (airframe model) - [Boeing 727-225](https://openairdocs.org/model/boeing-727-225): 2 aircraft (airframe model) - [Boeing 747-123](https://openairdocs.org/model/boeing-747-123): 2 aircraft (airframe model) - [Boeing 747-251F](https://openairdocs.org/model/boeing-747-251f): 2 aircraft (airframe model) - [Dehavilland DHC-7-103](https://openairdocs.org/model/dehavilland-dhc-7-103): 2 aircraft (airframe model) - [Lockheed L-1011-385-1](https://openairdocs.org/model/lockheed-l-1011-385-1): 2 aircraft (airframe model) - [Boeing 727-200F](https://openairdocs.org/model/boeing-727-200f): 1 aircraft (airframe model) - [Boeing 727-200](https://openairdocs.org/model/boeing-727-200): 1 aircraft (airframe model) - [Boeing 727-212](https://openairdocs.org/model/boeing-727-212): 1 aircraft (airframe model) All 40 models: https://openairdocs.org/ad/91-10-01/models.md Every aircraft: https://openairdocs.org/ad/91-10-01/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.