Airworthiness Directive Issued by FAA for IFD540 and Entegra Release 9
Emergency AD requires adding Limitations Section of the airplane flight manual or flight manual supplement.
Lincoln, MA – Monday, May 18, 2015 –
Avidyne Corporation, announced today that the Federal Aviation Administration (FAA) has issued an Emergency Airworthiness Directive (AD) to owners of Avidyne IFD540 and Entegra Release 9 FMS systems. The AD requires adding Limitations Section of the airplane flight manual or flight manual supplement.
“This AD has to do with how our software handles this specific leg type in these specific instances based on a discrepancy in the interpretation of the MOPS (Minimum Operational Performance Specifications). R9 systems have been flying with this software since 2009, and it wasn’t until very recently that we received a comment from a customer regarding this behavior of the system, which we immediately brought to the attention of the FAA,” said Tom Harper, Avidyne’s Director of Marketing & Communications. “During our investigation, we found there are 306 approaches that technically meet the criteria, however, all but 106 of these approaches are 1 degree or less different from the final approach course, and therefore not an issue. GPS approaches are being added all the time and back when R9 was first certified there were very few, if any, GPS approaches of this type. In addition, when flying a coupled approach, we found that the GPSS signal does not exhibit this offset so unless you were hand flying, like the customer who first identified this problem during a training flight, this behavior would not necessarily present itself. As mentioned, our engineers were able to determine the issue with the code, and we have identified and submitted a fix. We issued a Service Information Letter (SIL) to our IFD and R9 customers, and the FAA issued the AD. The software fix has been rolled into our Release 10.1 software and will be available very soon.”