Ad/RAD/51 Amdt 1 - Rockwell International/Collins Aviation Division Tdr-94d Transponder (Cth)

AIRWORTHINESS DIRECTIVE

On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/RAD/51 and issues the following AD under subregulation 39.001(1) of CASR 1998.  The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Radio Communication and Navigation Equipment

AD/RAD/51 Amdt 1 Rockwell International/Collins Aviation
Division TDR-94D Transponder 10/2008

Applicability:

Rockwell International/Collins Aviation Division TDR-94D Mode S Transponder, part number (P/N) 622-9210-002, installed on, but not limited to, the following aeroplanes:

Beechcraft 300 series.

Bombardier (de Havilland) DHC-8 series,

Bombardier (Canadair) Challenger CL-601 series,

British Aerospace HS 125-700 series,

Dassault Mystere-Falcon 200 and 900,

Grumman Gulfstream G1159 series,

Saab 340A and 340B, and

Short Brothers SD3-60.

Requirement:

1.    If not previously accomplished in accordance with the original issue of this Directive or United States Federal Aviation Administration (FAA) AD 93-04-02, fabricate a placard with the following words in letters at least 25mm in height and install the placard within the pilot’s clear view on the instrument panel:

            ‘OPERATION OF TCAS II IN ANY MODE OTHER
THAN THE “TA ONLY” MODE IS PROHIBITED’

2.    If not previously accomplished in accordance with the original issue of this Directive or FAA AD 93-04-02, modify the software of the transponder in accordance with the Accomplishment Instructions of Collins Service Bulletin TDR-94/94D-34-6 Revision 2 dated 21 September 1992. (The placard mandated by Requirement 1 is no longer necessary after this Modification is incorporated.)

Note:  FAA AD 93-04-02 Amendment 39-8504 refers.

Compliance:

For Requirement 1 - Prior to 25 October 2008.

For Requirement 2 - Prior to 1 December 2008.
This Amendment becomes effective on 25 September 2008.
Background:	Tests have revealed that these Mode S Transponders, when operating in the resolution advisory mode, may loose the capability of co-ordinating with other aircraft.  This could result in a near miss situation or mid-air collision.  Compliance with this Directive is intended to prevent collisions or near misses caused by failure of these Mode S Transponders.
This Amendment results from a request from industry to identify the affected transponder, the amendment adds P/N 622-9210-002 to the applicability statement, updates the list of affected aircraft and corrects minor typographical errors.
The original issue of this Directive became effective on 27 May 1993.

James Coyne
Delegate of the Civil Aviation Safety Authority

6 August 2008