Story ID: 
Archangel AHR75 AHRS Receives TSO
By: Matt Thurber
Caption: The lightweight MEMS-based AHRS is approved in the U.S. and Europe.
Word Count: 199
The FAA granted technical standard order (TSO) approval to Archangel Systems for its AHR75 attitude and heading reference system. The TSO is also automatically certified in Europe, according to Archangel because, “The FAA and EASA agree that all TSOs granted after March 2, 2016 apply bilaterally.” Deliveries of the AHR75 are scheduled to begin in April.

The AHR75 TSO is to the new C201 standard, “a much more stringent requirement for AHRS performance, particularly in rotorcraft.” Software certification is to Level A, “the highest level possible for mission-critical functions,” according to the company. 

The Archangel micro-electromechanical systems (MEMS)-based AHRS replaces traditional mechanical gyro-based instruments, and the AHR75 weighs five to 10 pounds less than a comparable gyro. Archangel is targeting the rotorcraft market with the AHR75, which has been selected by Marenco Swisshelicopter for the SKYe SH09. Even in rotorcraft applications, Archangel MEMS-base AHRS have a mean time between failure of more than 12,000 hours.

Last year Archangel received its first European TSO approval, for its AHR150A and AHR300A air data attitude heading reference systems (ADAHRS). The AHR75 doesn’t include the air-data sensors contained in the AHR150A and -300A.