CTHIn ForceLegislation
AD/RAD/82 - Prevent GPS Navigation unit from Providing Erroneous Cross-Deviation
//
© 2026 Zoe. All rights reserved.
Zoe is a legal information platform. Always consult the Federal Register of Legislation for authoritative text.
AD/RAD/82 - Prevent GPS Navigation unit from Providing Erroneous Cross-Deviation
Start here
Turn the raw legal text into a practical explanation grounded in AD/RAD/82 - Prevent GPS Navigation unit from Providing Erroneous Cross-Deviation.
Image unavailable in extracted text
Image unavailable in extracted text
AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (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.
Image unavailable in extracted text
Radio Communication and Navigation Equipment
AD/RAD/82 Prevent GPS Navigation unit from Providing
Erroneous Cross-Deviation
9/2004
Applicability: Garmin AT, formerly UPS Aviation Technologies, Apollo GX50/55/60/65 TSO- C129a global positioning system (GPS) navigation units as listed below with software versions 3.0 through 3.4 inclusive:
| Model | Part Number | Description | Modification Level |
|---|---|---|---|
| GX50 | 430-6050-400 | Approach Certified GPS | With any of the following mods:(H), (N), (P), (T) or (U);prior to (V) |
| 430-6050-401 | Approach Certified GPS | Prior to (V) | |
| 430-5060-402 | Approach Certified GPS | Prior to (V) | |
| GX55 | 430-6050-200 | Enroute/Terminal Certified GPS | With any of the following mods:(E), (J), (K), (M) or (N);prior to (R): |
| 430-6050-201 | Enroute/Terminal Certified GPS | With any of the following mods:(E), (J), (K), (M) or (N);prior to (R) | |
| 430-6050-202 | Enroute/Terminal Certified GPS | Prior to (R) | |
| 430-6050-203 | Enroute/Terminal Certified GPS | Prior to (R) |
| GX60 | 430-6050-600 | Approach CertifiedGPS/COM | With any of the followingmods: |
|---|---|---|---|
| (H), (N), (S), (AB) or(AC);prior to (AE) | |||
| 430-6050-601 | Approach Certified GPS/COM | With any of the following mods:(H), (N), (S), (AB) or (AC);prior to (AE) | |
| 430-6050-602 | Approach Certified GPS/COM | Prior to (AE) | |
| 430-6050-603 | Approach Certified GPS/COM | Prior to (AE) | |
| 430-6050-604 | Approach Certified GPS/COM | Prior to (AE) | |
| GX65 | 430-6050-800 | Enroute/Terminal Certified GPS/COM | With any of the following mods:(F), (L), (P), (Y) or (AA);prior to (AC) |
| 430-6050-801 | Enroute/Terminal Certified GPS/COM | With any of the following mods:(F), (L), (P), (Y) or (AA);prior to (AC): | |
| 430-6050-802 | Enroute/Terminal Certified GPS/COM | Prior to (AC) | |
| 430-6050-803 | Enroute/Terminal Certified GPS/COM | Prior to (AC) | |
| 430-6050-804 | Enroute/Terminal Certified GPS/COM | Prior to (AC) |
Note 1: The above table was sourced from UPS Aviation Technologies Service Bulletin 561-4002-001, dated 19 April 2002, which was referenced in FAA AD 2004- 13-20 and the certification in the table refers to the FAA TSO C-129a class of the unit.
Requirement: 1. Modify and test the software for the Apollo GX50/55/60/65 TSO-C129a GPS navigation unit by accomplishing all of the actions specified in paragraphs 3.B. and 3.C. of Service Bulletin (SB) 561-4002-001, dated 19 April 2002.
Note 2: FAA AD 2004-13-20 Amdt 39-13702 refers.
Compliance: For Requirement 1 - Within six months after the effective date of this Directive.
For Requirement 2 - Immediately following completion of Requirement 1. This Airworthiness Directive becomes effective on 2 September 2004.
Background: The United States Federal Aviation Administration (FAA) has advised that, under certain conditions, Garmin AT, Apollo GX series GPS navigation units with software versions 3.0 to 3.4 may provide erroneous cross-deviation information, which could result in the aircraft deviating from its intended course for a brief period of time. This erroneous information may place an excessive workload on the flightcrew while they monitor other available navigation data to avoid deviating off course.
To prevent the GPS unit from providing erroneous information, this Directive requires modification and testing of the software for the GPS navigation units.
Signature of Bernard Malcolm Hole Delegate of the Civil Aviation Safety Authority
Bernard Malcolm Hole
Delegate of the Civil Aviation Safety Authority 20 July 2004
Image unavailable in extracted text
The above AD is notified in the Commonwealth of Australia Gazette on 11 August 2004.