AD in the Works To Correct Garmin GNS 430 Anomalies

 - May 9, 2008, 5:39 AM

The FAA is planning to issue an AD to address what it says are potential safety hazards with the popular Garmin GNS 430 combination GPS/navcom. The agency said external electrical noise from autopilots and other cockpit systems could cause the electronic CDI/HSI in the unit to display inaccurate course deviations. The problems occur only in aircraft with electrical equipment or accessories, such as an autopilot, that send large voltage spikes to the unit, the FAA said. A Service Bulletin issued by Garmin explains how to modify the GNS 430’s circuit boards to correct the anomaly. The FAA estimates that about 2,000 GNS 430s could be affected in the U.S. It is accepting comments on the proposed AD until September 21.