FAA: Helo ELTs Affected by Possible G-Switch Failures

 - June 21, 2019, 12:03 PM

An FAA Special Airworthiness Information Bulletin (SAIB CE-19-12) alerts owners of certain serial numbered Artex emergency locator transmitters G406-4, C406-1, C406-1HM, C406-2, C406-2HM, C406-N, and C406-NHM installed in helicopters that they may not transmit alert and location signals in case of an accident due to an inoperative or a deteriorated G-switch. The agency has received reports of ACR Electronics ELT model C406 failures because the G-switch was inoperative. 

Specifically, ELTs located in high-vibration environments “could have its acceleration sensor deteriorate and fail after five years,” said the FAA. To address this condition, ACR Electronics has published Service Bulletin (SB) 1000A, identifying those ELTs fitted with the original G-switch, prescribing testing replacement of the G-switch at five-year intervals, or alternatively, reducing the normal inspection intervals after five years of service.   

The FAA said an ELT that has been previously modified with a new hermetically sealed longitudinal G-switch (P/N A1-12-0135) is sufficient to address the concerns of this SAIB. Similar SAIBs have been issued by Australia’s Civil Aviation Safety Authority and the European Union Aviation Safety Agency.  

An ACR Electronics spokesman could not identify how many units are covered by the SAIB, but told AIN that Artex ELTs have been in production for four decades, and that Artex is a “market leader for ELTs on general aviation aircraft up to the largest commercial aircraft flying today.”