May 12, 2015
An NBAA webinar, set for 1 p.m. (EDT) May 27, will discuss an alternate method of compliance (AMOC) for validating required navigation performance authorization required (RNP AR) approach data, which puts this capability within reach of business aircraft operators. Members must pre-register for this free webinar, which is sponsored by Jeppesen.
“More efficient, economical and automatic than the current burdensome process, RNP AR potentially gives business aircraft operators access to more airports and procedures that provide better minimums and savings of fuel and time,” said Bob Lamond, NBAA’s director of aircraft traffic services and infrastructure.
The validation process prescribed by Advisory Circular 90-101A requires operators (or contractors) to verify the accuracy of approach databases with the original government data, said Andrew Riedel, manager of Jeppesen’s corporate technical standards and the RNP AR webinar’s co-leader. “Primarily only commercial operators have the resources needed” for this complex process, he said.
“A typical RNP AR approach requires more than 350 accuracy checks,” said Clay Barber, Garmin aviation product engineering team principal engineer and webinar co-leader. “For a single approach, that is more than 4,500 accuracy checks a year for all 13 database cycles. Multiply that by the number of RNP AR approaches flown.”
Formats unique to each government’s source data complicate the process. And this data does not include – and equipment does not always display – all the parameters that must be verified. The AMOC avoids these challenges with an overlapping validation process that turns the government data into a navigation database.
Jeppesen validates the ARINC 424 file it creates from the government data. Garmin validates the packed binary navigation database it builds from the ARINC 424 file. When the navigation database is loaded on the aircraft, with every activation of the avionics, the cyclic redundancy check (CRC) verifies the entire database against the packed database. FAA approved, this AMOC relieves operators of validation requirements.
Regardless of the RNP AR status of their aircraft, NBAA Members should pre-register and participate in this free webinar, urged Lamond. RNP AR expands capabilities, and data validation is a continuing airworthiness requirement that forever follows an aircraft’s initial authorization.