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The ABC’s of ADAHRS OR Great things do come in small packages.

Aviation loves acronyms. Take ADAHRS for example: everyone has read about it, but few really know what it is or the story behind it. Today’s Air Data, Attitude and Heading Reference Systems (ADAHRS) are true marvels of technology. And their pinpoint accuracy, reliability and compact size is at the center of many of today’s most advanced avionics systems.

While its development is an interesting story in itself, the Reader’s Digest version is that ADAHRS came along as a non-mechanical replacement for legacy mechanical sensors like vertical and direction gyros. You remember them. Their spinning mass gyros took a few minutes to get up to speed before you could taxi the aircraft. This was because the delicate nature of their gimbals and bearings were easily damaged.

Because of their intricate design, these mechanical systems had extremely high failure rates. “gyro failure” kept a lot of aircraft on the ground and was the root cause of many accidents.

Chelton Flight Systems, (one of the companies that today makes up Genesys Aerosystems), was a pioneer in the development of the early ADAHRS sensors. These compact, highly capable and highly reliable units were crucial to the company developing its first EFIS system. Because ADAHRS use a combination of various microelectromechanical accelerometers, rate-, pressure- and magnetic data sensors, as well as input from other avionics on the aircraft, it delivers air data, attitude, and heading reference information that is much more accurate and reliable than was ever possible with the old gyro-based systems.

And since ADAHRS is all solid-state, all of the computations required to provide the information is all contained in the system’s software. It adds up to much greater avionics accuracy and reliability. For example, where older gyro units would be able to provide data in the one to 1.5 degree accuracy range, a Genesys ADAHRS unit is able to provide data in the 1/10th of a degree or better range. The best in the avionics business.

Greater accuracy isn’t the only benefit a Genesys ADAHRS system offers. Since many of our EFIS customers operate in both the Arctic and Antarctic regions, being so close to the magnetic North and South Poles can create havoc in some sensors. Not the Genesys ADAHRS.

Our ADAHRS feature a “Free” mode, which allows our technology to be used near the polar latitudes or in areas of high magnetic degradation with no loss of data accuracy. When the magnetic fields are too erratic for stable operations the Free-mode decouples the accelerometers and rate sensors inside the ADAHRS from the magnetic data sent by the Magnetic Sensor Unit (MSU).

This gives pilots flying in these extreme magnetically deviant conditions the information they need to navigate more accurately than was previously possible in these areas of the world.

Our new-generation ADAHRS system is just one example of how Genesys Aerosystems systems are used around the world to make flying safer.


Until next time, fly safely,