Radio Communication and Navigation Equipment
AD/RAD/58
Amdt 1
AlliedSignal CAS-81 TCAS II 7/98
Applicability: AlliedSignal Commercial Avionics Systems CAS-81 Traffic Alert and Collision Avoidance Systems (TCAS), with serial numbers below 6066.
Note: CAS-81 TCAS II equipments are known to be installed on, but not limited to, the following aircraft series:
Aerospatiale ATR-42, ATR-72
Airbus Industries A300, A310, A320, A321, A330 and A340 Beech 1900 and BE-65 through BE-90
Boeing 727, 737, 747, 757, 767 and 777
Convair CV-580
de Havilland DHC-7 and DHC-8
Embraer EMB-120
Fairchild F227
Fokker F28 Mk 100, Mk 1000 and Mk 4000
General Dynamics Convair 340 and 440 Gulfstream G-159 and G-IV
Lockheed L1011
McDonnell Douglas DC-8, DC-9, DC-10, MD-11 and MD-80 Rockwell International NA-265-65
SAAB 340
Shorts 360
COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 107 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Requirement: Amend the Limitations Section of the Aircraft Flight Manual to include the following:
“In order to ensure that the audio output of the CAS-81 TCAS operates properly, accomplish the following:
- Prior to the first flight of the day; prior to the accumulation of 10 hours of uninterrupted power; and at the mid-point of any one flight scheduled to exceed 10 hours: Cycle the power to the TCAS Processor via the circuit breaker or power bus.
b. Prior to taxi before take-off: Initiate the TCAS functional test in accordance with the procedures in the Aircraft Flight Manual to verify the operational condition of the CAS-81 TCAS.”
Alternately,
If the aircraft manufacturer has substantiated 30ºC as a maximum ambient for the TCAS processor location amend the Limitations Section of the Aircraft Flight Manual to include the following:
“In order to ensure that the audio output of the CAS-81 TCAS operates properly, accomplish the following:
Prior to each flight of up to 18 hours duration, reset the TCAS circuit breaker and conduct a TCAS self-test.”
Note 1: Applications for an amendment to the Aircraft Flight Manual should be made to the local CASA District Airworthiness Office.
Note 2: Tests may be performed by a flight crew member.
Note 3: Modification of the TAP-81A TCAS processor receiver in accordance with AlliedSignal Service Bulletin TPA-81A-34-82 dated January 1996 or TPA-81A-34-84 dated January 1996 is considered an optional terminating action for the requirement of this Directive. Following incorporation of the modifications the Flight Manual amendment may be removed (see Note 1).
Note 4: FAA AD 95-26-15 R1 Amdt 39-9824 refers.
Compliance: The original compliance of ‘Effective 3 January 1996’ remains unchanged.
This amendment becomes effective on 18 June 1998.
Background: The FAA has received reports of failure of the audio output of CAS-81 TCAS. This condition could result in the CAS-81 TCAS failing to perform its collision avoidance function.
The original issue of this Directive required a revision to the Aircraft Flight Manual to provide the flightcrew with procedures to cycle power to the TCAS processor via the circuit breaker or power bus and to perform a TCAS functional test to verify proper operation of the TCAS.
This Amendment amends the title of the Directive, identifies the serial number range of the effected equipment and introduces an optional terminating action, whereby the original flight manual amendment may be removed. It also introduces an alternative flight manual amendment, which may be used if the aeroplane manufacturer has substantiated 30º C as a maximum ambient temperature for the TCAS processor location.
The original issue of this airworthiness directive became effective on 3 January 1996.
Overview
The Civil Aviation Safety Authority (CASA) introduced the "Radio Communication and Navigation Equipment AD/RAD/58Amdt 1 AlliedSignal CAS-81 TCAS II 7/98" as an amendment to the Aircraft Flight Manual to address the reported failures in the audio output of the AlliedSignal CAS-81 Traffic Alert and Collision Avoidance Systems (TCAS). This legislative instrument was enacted in 1998 to enhance aviation safety by ensuring the proper operation of TCAS equipment, which is crucial for collision avoidance. The directive applies specifically to CAS-81 TCAS systems with serial numbers below 6066, installed in a variety of aircraft models such as the Airbus A320, Boeing 737, and others. The primary objective is to mandate regular power cycling and functional testing of the TCAS to prevent potential system failures that could compromise flight safety. CASA requires operators to amend their Aircraft Flight Manuals accordingly and provides for an optional modification of the TCAS processor as a terminating action for compliance.
Scope and Application
The F2006B06512 legislative instrument pertains to the regulation of AlliedSignal Commercial Avionics Systems CAS-81 Traffic Alert and Collision Avoidance Systems (TCAS) installed in specific aircraft. This Act applies to aircraft equipped with CAS-81 TCAS with serial numbers below 6066, including those installed on various aircraft series such as the ATR-42, A300, 737, and others. The directive is part of the Commonwealth of Australia's Civil Aviation Regulations 1998, under Part 39 - 107 Civil Aviation Safety Authority, Schedule of Airworthiness Directives, and is aimed at ensuring the proper operation of TCAS equipment to prevent potential collision avoidance failures. The requirement includes amendments to the Aircraft Flight Manual to mandate specific procedures for cycling the TCAS power and conducting functional tests, with an option to remove the flight manual amendment if certain modifications are made to the TCAS processor. Compliance with this directive is mandatory, with its original effective date remaining unchanged at 3 January 1996, and the amendment becoming effective on 18 June 1998.
Key Provisions
The Civil Aviation Regulations 1998 (sections relevant to airworthiness) require that the Aircraft Flight Manual (AFM) for specific AlliedSignal CAS-81 TCAS II equipment be amended to include procedures to ensure the proper operation of the Traffic Alert and Collision Avoidance System (TCAS). Section 39-107 of the Regulations mandates that for TCAS systems with serial numbers below 6066, the AFM must include instructions to cycle the power to the TCAS Processor via the circuit breaker or power bus at specific intervals. These intervals include before the first flight of the day, before the accumulation of 10 hours of uninterrupted power, and at the midpoint of any flight exceeding 10 hours. Additionally, a TCAS functional test must be initiated before taxi before take-off to verify the operational condition of the CAS-81 TCAS. Alternatively, if the aircraft manufacturer has confirmed that 30°C is the maximum ambient temperature for the TCAS processor location, the AFM must include instructions to reset the TCAS circuit breaker and conduct a TCAS self-test prior to each flight of up to 18 hours duration.
The obligations imposed by these regulations are clear. Aircraft operators must ensure that the AFM for affected TCAS systems is updated to include the specified procedures. These procedures must be followed to maintain the operational integrity of the TCAS system, thereby ensuring the safety of all flights using the affected equipment. Operators must also ensure that the optional terminating action, which involves modifying the TAP-81A TCAS processor receiver in accordance with AlliedSignal Service Bulletins TPA-81A-34-82 or TPA-81A-34-84, is considered if applicable. Compliance with these requirements is mandatory, and failure to adhere to them could result in serious safety implications.
Any breach of the Civil Aviation Regulations 1998 in relation to these airworthiness directives could result in significant civil and criminal consequences. The primary concern is the potential for the TCAS to fail, leading to a collision avoidance system malfunction. This could result in severe safety risks and could be considered a violation of safety regulations. Under Australian law, breaches of such safety regulations could result in fines and imprisonment for individuals and organisations. The specific penalties would depend on the severity of the breach and the impact on aviation safety. For instance, if the non-compliance leads to an accident or serious incident, the penalties could be substantial, reflecting the seriousness of endangering public safety.