# AD 94-01-04: Traffic Alert and Collision Avoidance System

- Type: Airworthiness directive
- Status: Current
- Products: Airbus A300 B4-601, A300 B4-603, A300 B4-605R, A300 B4-620, A300 B4-622, A300 B4-622R, A300 C4-605R Variant F, A300 F4-605R, A300 F4-622R, A310-203, A310-204, A310-221 and 127 more
- Effective: February 4, 1994
- Published: January 5, 1994, 59 FR 511–514
- Issued as: Final rule
- Superseded by: Nothing supersedes this AD
- Product type: Appliance
- Amendment: 39-8786
- Docket: 93-NM-68-AD
- Registered aircraft: 5,314 may be affected, by airframe or engine model (OpenAirDocs)
- Federal Register: https://www.federalregister.gov/documents/1994/01/05/93-32115/airworthiness-directives-honeywell-traffic-alert-and-collision-avoidance-system-ii-computer-units-as
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/D152E7A21A278EBE86256A450050F270.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/94-01-04

## The airworthiness directive

94-01-04 HONEYWELL: Amendment 39-8786. Docket 93-NM-68-AD.

Applicability: Traffic Alert and Collision Avoidance System (TCAS) II computer units; part numbers 4066010-901, -902, and -903; as installed on, but not limited to, the following airplanes, certificated in any category:

Airbus Industrie Model A300-600, A310-200, A310-300, A320-200, and A340 series airplanes; Boeing Model 727-100 and -200; 737-100, -200, -300, -400, and -500; 747-100, -200, -300, -400 and 747SP; 757-200; and 767-200 and -300 series airplanes; Cessna Citation Model C550 and C560 series airplanes, and Cessna Citation III and VII series airplanes; Canadair Challenger Model CL-600-2B16 and -2A12 series airplanes; British Aerospace Model 125-800A; Gulfstream Model GII, GIIB, GIII, and GIV series airplanes; Lockheed Model L-1011 series airplanes; McDonnell Douglas Model DC-9-10, -20, -30-, -40, and -50; DC-10-10, -15, -30, and -40; MD-11; and DC-9-80 series airplanes; and Model MD-88 airplanes; Dassault Aviation Model Mystere-Falcon 50 and 900 series airplanes; Short Brothers Model SD3-60 series airplanes; de Havilland Model DHC-8-100 and DHC-7 series airplanes; Fokker Model F27 series airplanes; and Corporate Jets Limited Model BAe 125-800A and BAe 125-1000A series airplanes.

Compliance: Required as indicated, unless accomplished previously.

To prevent collisions or near misses caused by incompatibility between the TCAS II processors and the current air traffic control system, accomplish the following:

  (a) Before December 31, 1994, accomplish the requirements of paragraphs (a)(1) and (a)(2) of this AD in accordance with Honeywell Service Bulletin 4066010-34-SW16, dated December 20, 1993.

  (1) Remove existing Honeywell TCAS II computer units, part numbers 4066010-901, -902, and -903, and replace those units with new units that incorporate updated collision avoidance system (CAS) logic, identified as Version 6.04A in Mitre letter F046-L-0069, dated September 21, 1993.

  (2) Modify the computer surveillance logic on Honeywell TCAS II computer units, part numbers 4066010-901, -902, and -903, to ensure that these units accommodate Mode C altitude input of 100-foot increments and that the system will be tracked and coordinated by intruding aircraft when the Mode S transponder CA field is set at CA=7.

  (b) Prior to further flight after accomplishing the requirements of paragraph (a) of this AD, revise the Airplane Flight Manual (AFM) or AFM Supplement by accomplishing either paragraph (b)(1) or (b)(2) of this AD.

  (1) Revise the Normal Procedures Section of the AFM to include the appropriate TCAS operating characteristic relative to the modifications required by paragraph (a) of this AD, in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Or

  (2) Revise the Normal Procedures Section of the AFM to include thefollowing TCAS operating characteristic relative to the modification required by paragraph (a) of this AD. This may be accomplished by inserting a copy of this AD in the AFM or AFM Supplement.

"All Resolution Advisory (RA) and Traffic Advisory (TA) aural messages are inhibited at a radio altitude of less than 1,100 feet above ground level (AGL) climbing, and less than 900 feel AGL descending."

  (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, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Avionics Inspector, who may add comments and then send it to the Manager, Los Angeles ACO.

NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO.

  (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 and modification shall be done in accordance with Honeywell Service Bulletin 4066010-34-SW16, dated December 20, 1993. 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 Honeywell Inc., Commercial Flight Systems Group, Air Transport Systems Division, P.O. Box 21111, Phoenix, Arizona 85036. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; at the FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3229 East Spring Street, Long Beach, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

  (f) This amendment becomes effective on February 4,1994.

## Affected data sheets (19) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A6WE](https://openairdocs.org/tcds/A6WE): The Boeing Company; names 20 of 25 models: DC-9-12, DC-9-15F, MD-88, DC-9-41, DC-9-13, DC-9-34F, DC-9-81 (MD-81), DC-9-33F…
- [TCDS A35EU](https://openairdocs.org/tcds/A35EU): Airbus SAS; names 17 of 17 models: A310-203, A300 B4-622R, A300 F4-605R, A300 B4-601, A310-204, A310-221, A300 B4-603, A300 B4-622…
- [TCDS A13NM](https://openairdocs.org/tcds/A13NM): De Havilland Aircraft of Canada Limited; names 12 of 16 models: DHC-8-101, DHC-8-102, DHC-8-103, DHC-8-106, DHC-8-201, DHC-8-202, DHC-8-301, DHC-8-311…
- [TCDS A20WE](https://openairdocs.org/tcds/A20WE): The Boeing Company; names 11 of 14 models: 747-100B Series, 747SP Series, 747-400D Series, 747-400F Series, 747-200B Series, 747-200F Series, 747-300 Series, 747-200C Series…
- [TCDS A-817](https://openairdocs.org/tcds/A-817): Fokker Services B.V.; names 8 of 8 models: F27 Mark 500, F27 Mark 100, F27 Mark 700, F27 Mark 200, F27 Mark 400, F27 Mark 600, F27 Mark 050, F27 Mark 300
- [TCDS A22WE](https://openairdocs.org/tcds/A22WE): The Boeing Company; names 8 of 11 models: DC-10-40, MD-11, DC-10-10F, DC-10-30, DC-10-30F (KC-10A KDC-10), DC-10-10, DC-10-15, MD-11F
- [TCDS A43NM](https://openairdocs.org/tcds/A43NM): Airbus SAS; names 8 of 8 models: A340-541, A340-311, A340-313, A340-211, A340-312, A340-213, A340-642, A340-212
- [TCDS A16WE](https://openairdocs.org/tcds/A16WE): The Boeing Company; names 6 of 17 models: 737-500 Series, 737-100 Series, 737-200C Series, 737-300 Series, 737-200 Series, 737-400 Series
- [TCDS A28NM](https://openairdocs.org/tcds/A28NM): Airbus SAS; names 6 of 50 models: A320-211, A320-212, A320-214, A320-231, A320-232, A320-233
- [TCDS A12EA](https://openairdocs.org/tcds/A12EA): Gulfstream Aerospace Corporation; names 5 of 7 models: GIV-X, G-1159A, G-IV, G-1159B, G-1159
- [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 A23WE](https://openairdocs.org/tcds/A23WE): Lockheed Martin Corporation; names 4 of 4 models: L-1011-385-1-14, L-1011-385-3, L-1011-385-1, L-1011-385-1-15
- [TCDS A3WE](https://openairdocs.org/tcds/A3WE): The Boeing Company; names 4 of 6 models: 727-100 Series, 727-200 Series, 727-100C Series, 727-200F Series
- [TCDS A1NM](https://openairdocs.org/tcds/A1NM): The Boeing Company; names 3 of 5 models: 767-300 Series, 767-200 Series, 767-300F Series
- [TCDS A2NM](https://openairdocs.org/tcds/A2NM): The Boeing Company; names 3 of 4 models: 757-200CB Series, 757-200PF Series, 757-200 Series
- [TCDS A21EA](https://openairdocs.org/tcds/A21EA): Bombardier Inc.; names 2 of 5 models: CL-600-2A12 (601), CL-600-2B16 (604 Variant)
- [TCDS A22CE](https://openairdocs.org/tcds/A22CE): Textron Aviation Inc.; names 2 of 6 models: 550, 560XL
- [TCDS A3EU](https://openairdocs.org/tcds/A3EU): Textron Aviation Inc.; names 2 of 50 models: BAe.125 Series 1000A, BAe.125 Series 800A (U-125)
- [TCDS A46EU](https://openairdocs.org/tcds/A46EU): Dassault Aviation; names 2 of 3 models: Mystere-Falcon 900, Mystere-Falcon 50

## 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: 5,314 (5,314 by airframe model, 0 by engine model)
- Makers: Cessna 1,681, Boeing 794, Gulfstream Aerospace 663, Bombardier 489, Airbus 430, Airbus Industrie 260, Mcdonnell Douglas 224, Canadair 157, Textron 142, Dassault 140

Models with the most aircraft:

- [Cessna 560](https://openairdocs.org/model/cessna-560): 596 aircraft (airframe model)
- [Cessna 560XL](https://openairdocs.org/model/cessna-560xl): 581 aircraft (airframe model)
- [Cessna 550](https://openairdocs.org/model/cessna-550): 500 aircraft (airframe model)
- [Bombardier CL-600-2B16](https://openairdocs.org/model/bombardier-cl-600-2b16): 388 aircraft (airframe model)
- [Gulfstream Aerospace G-IV](https://openairdocs.org/model/gulfstream-aerospace-g-iv): 357 aircraft (airframe model)
- [Gulfstream Aerospace GIV-X (G450)](https://openairdocs.org/model/gulfstream-aerospace-giv-x-g450): 237 aircraft (airframe model)
- [Airbus A320-232](https://openairdocs.org/model/airbus-a320-232): 188 aircraft (airframe model)
- [Boeing 767-300F](https://openairdocs.org/model/boeing-767-300f): 169 aircraft (airframe model)
- [Airbus A320-214](https://openairdocs.org/model/airbus-a320-214): 160 aircraft (airframe model)
- [Textron 560XL](https://openairdocs.org/model/textron-560xl): 141 aircraft (airframe model)
- [Canadair CL-600-2B16](https://openairdocs.org/model/canadair-cl-600-2b16): 134 aircraft (airframe model)
- [Airbus Industrie A320-232](https://openairdocs.org/model/airbus-industrie-a320-232): 109 aircraft (airframe model)
- [Mcdonnell Douglas MD-11F](https://openairdocs.org/model/mcdonnell-douglas-md-11f): 100 aircraft (airframe model)
- [Dassault MYSTERE-FALCON 50](https://openairdocs.org/model/dassault-mystere-falcon-50): 88 aircraft (airframe model)
- [Dassault-Breguet MYSTERE FALCON 900](https://openairdocs.org/model/dassault-breguet-mystere-falcon-900): 73 aircraft (airframe model)
- [Boeing 757-232](https://openairdocs.org/model/boeing-757-232): 63 aircraft (airframe model)
- [British Aerospace BAE 125 SERIES 800A](https://openairdocs.org/model/british-aerospace-bae-125-series-800a): 59 aircraft (airframe model)
- [Dassault MYSTERE FALCON 900](https://openairdocs.org/model/dassault-mystere-falcon-900): 52 aircraft (airframe model)
- [Mcdonnell Douglas DC-9-83(MD-83)](https://openairdocs.org/model/mcdonnell-douglas-dc-9-83-md-83): 49 aircraft (airframe model)
- [Boeing 767-332](https://openairdocs.org/model/boeing-767-332): 46 aircraft (airframe model)

All 230 models: https://openairdocs.org/ad/94-01-04/models.md
Every aircraft: https://openairdocs.org/ad/94-01-04/aircraft.md

No proposed rule in this release led to it. Its text cites no advisory circulars or STCs.

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