Crossbow Technology has just received FAA certification for the AHRS500GA, the first stand-alone micro-electro-mechanical system (MEMS) attitude heading reference system (AHRS). Stand-alone means the Crossbow AHRS operates independently and does not require Air Data or GPS inputs for correct operation.

Only Standalone FAA Certified MEMS AHRS

The Crossbow AHRS500GA is a high performance, solid-state attitude and heading reference system intended for general aviation aircraft. This high reliability inertial system provides attitude and heading measurement with static and dynamic accuracy superior to traditional spinning mass vertical and directional gyros. Dean Johnson, Vice President for Inertial Systems, says "Crossbow is the first to offer the General Aviation pilot the reliability of solid-state MEMS sensors in a low cost AHRS that meets all the FAA TSO certification requirements. The AHRS500 is designed for the future and has passed the tough new multiple lightning strike test as part of its qualification testing."

Automotive Sensor Technology Harnessed

The sensor technology of the AHRS500 was developed for the automotive industry, which makes the technology highly reliable and potentially affordable for general aviation pilots. The raw performance of these devices is geared toward fairly coarse inertial applications, such as skid detection. John Crawford, vice president of sales for Crossbow, says "Crossbow started with the automotive industry's low-cost, highly reliable, but low-performing sensors and invested six years,of R&D in calibration approaches, packaging, software algorithms and environmental design. The result is a flight-proven AHRS that requires no additional or aiding input from Air Data or GPS to meet FAA performance requirements. That is the real breakthrough here."

Viable Alternative To Spinning Gyros

In fact, this technology permits general aviation pilots to have the same attitude and heading benefits of the ring laser gyro-based INS system in a transport category aircraft. "The difference is that an INS system may cost upwards of $100,000, but it operates on the same principle. The AHRS500 provides a new and clear alternative to unreliable spinning gyros or costly INS systems," says Crawford. The AHRS500 also includes a comprehensive built-in test function, similar to high-end INS systems, that continuously monitors the AHRS for proper operation.

Crossbow flight testing of the AHRS500 against a high-end inertial navigation system (INS) proves the accuracy of the AHRS500 is better than that of the vacuum driven gyros in most aircraft. The AHRS500 is designed to meet all FAA requirements and is certified to TSO 4 (Bank and Pitch) and 6 (Heading).

FMI: www.xbow.com