EAA Supports Revision Of The Flight Testing Guidance Advisory Circular Which Applies To Amateur Built Aircraft

The FAA has published revision “B” to Advisory Circular (AC) 90-89, the Amateur Built Aircraft and Ultralight Flight Testing Handbook. The AC, first published in 1989 with extensive input from EAA, was last revised in 1995.

AC 90-89 has formed the foundation for flight testing standards of experimental amateur built aircraft. When an amateur built aircraft receives its special airworthiness certificate, it is assigned a flight testing period of time that must be accomplished prior to carrying passengers. That’s where AC 90-89 comes into play. As the builder of an amateur built aircraft, is vitally important to be familiar with this important advisory circular.

EAA fully supported the most recent revision, and supplied the bulk of the changes with the help of volunteer experts on the Homebuilt Aircraft Council and Board of Directors Safety Committee. Changes include new and better detailed guidance on fuel flow testing prior to the first flight, the use of GPS data to confirm the accuracy of pitot-static derived airspeed readings, stall testing, use of angle of attack systems, and more.

The revision also includes guidance recommended by the GA Joint Steering Committee (GA-JSC), a partnership of the GA community, government, and academia focused on improving safety without increasing regulation. The GA-JSC’s recommended guidance includes giving closer consideration to lateral center of gravity (such as when flight testing with unbalanced wing-mounted fuel tanks) and flight testing after a major or minor modification.

“This advisory circular is truly a living, community-created document,” said Sean Elliott, EAA vice president of advocacy and safety. “We are glad the FAA continues to solicit community input to keep AC 90-89 relevant to today’s technology and best practices. We encourage our members to read this document carefully and incorporate any guidance they deem relevant into their flight testing programs.”

FMI: www.eaa.org