Airworthiness Directive · Amendment 39-13702 · Aircraft Equipped With Garmin AT, Apollo GX Series Global Positioning System (GPS) Navigation Units With Software Versions 3.0 through 3.4 Inclusive
Aircraft Equipped With Garmin AT, Apollo GX Series Global Positioning System (GPS) Navigation Units With Software Versions 3.0 through 3.4 Inclusive
Aircraft equipped with Garmin AT, Apollo GX50/55/60/65 TSO-C129a global positioning system (GPS) navigation units with software versions 3.0 through 3.4 inclusive; as listed in UPS Aviation Technologies Service Bulletin 561-4002-001, dated April 19, 2002; certificated in any category.
This amendment adopts a new airworthiness directive (AD), applicable to aircraft equipped with Garmin AT, Apollo GX series GPS navigation units with software versions 3.0 through 3.4 inclusive, that requires modification and testing of the software for Apollo GX50/55/ 60/65 TSO-C129a GPS navigation units; and reidentification of the part. This action is necessary to prevent the GPS navigation unit, under certain conditions, from providing erroneous cross-deviation information, which could result in the aircraft deviating from its intended course for a brief period of time. Erroneous information may also place an excessive workload on the flightcrew while they monitor other available navigation data to avoid deviating off course. This action is intended to address the identified unsafe condition.
To prevent the GPS navigation unit, under certain conditions, from providing erroneous cross-deviation information, which could result in the aircraft deviating from its intended course for a brief period of time; and to also prevent erroneous information from placing an excessive workload on the flightcrew while they monitor other available navigation data to avoid deviating off course; accomplish the following:
(a) Within 6 months after the effective date of this AD, do the actions specified in paragraphs (a)(1) and (a)(2) of this AD, according to the Accomplishment Instructions of UPS Aviation Technologies Service Bulletin 561-4002-001, dated April 19, 2002.
(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 the service bulletin.
(2) Reidentify the modified Apollo GX50/55/60/65 TSO-C129a GPS navigation unit, according to paragraph 3.D. of the service bulletin.
(b) In accordance with 14 CFR 39.19, the Manager, Seattle Aircraft Certification Office, FAA, is authorized to approve alternative methods of compliance (AMOCs) for this AD.
