The widespread presence of angle-of-attack indicators in general aviation aircraft could reduce fatal loss-of-control accidents caused by inadvertent stalls, said the FAA, announcing an initiative to promote installing the devices in aircraft and educate pilots in their use.
In an Information for Operators (InFO) publication released July 25, the FAA’s Flight Standards Service called for voluntary installation of angle-of-attack (AOA) based systems in GA aircraft as original equipment and for retrofitting. The InFO, geared toward airmen, builds on a previously issued policy memo from the agency’s Aircraft Certification Service on "streamlining the design and production approval process of non-required/supplemental AOA-based systems for GA airplanes."
In urging that general aviation embrace AOA-based systems for safety, the FAA cited the work of the General Aviation Joint Steering Committee (GAJSC), which AOPA co-chairs, and a study of 2,472 fatal general aviation accidents that found that in-flight loss of control was the most prevalent cause. A General Aviation Joint Steering Committee working group then analyzed loss-of-control accidents and issued recommendations for safety improvements.
Using a data-driven approach to identify risks and trends through root cause analysis, the working group concluded in March 2013 "that the use of AOA-based systems by the GA community is an effective method for reducing" the likelihood of loss of control accidents during the approach and landing phases in the future.
The data also showed that "general aviation makes very little use of angle-of-attack systems for stall avoidance, but a properly installed AOA system, coupled with a pilot with an understanding and training on how to use it could be a key tool in avoiding loss of control," said David Oord, AOPA manager of regulatory affairs and the working group’s co-chair.
By providing direct information of the wing’s angle-of-attack, an AOA system makes it simpler for pilots to maintain awareness during critical or high-workload phases of flight. An AOA system’s output will help pilots maintain aircraft control "regardless of weight, airspeed, bank angle, density altitude, configuration, or center of gravity," Oord said.
The FAA also saw potential value in AOA systems in pilot training, noting initial research on safety benefits from aircraft equipped with AOA systems at Embry-Riddle Aeronautical University.
Through its InFO document, the agency urged flight instructors and pilots to review the operational information provided by manufacturers of AOA systems installed in aircraft they fly; urged aircraft owners and maintenance professionals to review the memo on the streamlined AOA system approval process; and suggested that providers of flight training develop and integrate AOA-system subject material into flight and ground school programs.
"We are also encouraging our members to read the InFO, check out the new and innovative AOA systems that are coming out, and consider installing and using one in their aircraft," Oord said. "The benefits from these relatively simple devices could be lifesaving."