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Less Than 50 Percent Of Textron Fleet Has Implemented FAA AD 2021-08-07

October 2022

Collins GPS 4000s.PNGAccording to Collins Aerospace, 650 Rockwell Collins GPS-4000S (P/N 822-2189-100) units remain installed on various make/model Citation aircraft, causing serious concerns about future parts availability as FAA (Federal Aviation Administration) AD (airworthiness directive) 2021-08-07 deadline approaches.

If you operate one of the remaining 650 Citations with these units, you have until the AD deadline of May 12, 2023, to upgrade to P/N 822-2189-101 via an exchange or factory repair. The longer you wait, the more likely you will get caught up in the bottleneck when the demand for these units increases and supply becomes scarce. 

The next scheduled update to the GPS constellation is June 11, 2023, causing a repeat of the “leap second” issue and rendering all -100 units useless.

This AD was prompted by an un-annunciated GPS vertical error that could result in a hazardously misleading LPV glidepath. It was issued to prevent a misleading GPS position on an LPV approach.

Rockwell Collins covers two hours of labor per unit and $100 freight.

We want to do everything we can to help and be part of the solution. Contact any of Duncan Aviation’s Satellite facilities (https://www.duncanaviation.aero/locations/#satellites) to schedule.


Photo of Chuck Zahnow Chuck Zahnow Airframe Tech Rep Citation, Hawker Battle Creek, MI (BTL) +1 269.969.8422