Light sport amphibian manufacturer Icon Aircraft has completed testing of its angle of attack (AoA) system - a key safety feature of the A5 aircraft, and the first of a new breed of stall warning systems in development by the general aviation industry.

The first details of the system released by Icon reveal that the A5's AoA gauge presents a graphical indication of the aircraft's margin using a tricolour scheme, with green indicating stable flight, yellow showing approach to stall and red signalling the wing is stalling.

Although quite common on military fighters and turbine-powered private aircraft, such AoA systems are "rarely seen" in the general aviation sector, Icon Aircraft says.

Greg Bowles, director of engineering and manufacturing for industry advocate General Aviation Manufacturers Association, agrees with Icon's description.

"It is accurate to say an AoA system is very, very rare in light [general aviation] today," Bowles says.

Icon's system is the first of several now in development, he adds. The renewed appreciation for a system that indicates the angle of the wing to the relative wind direction - or AoA - follows the progress of a new standard currently being drafted by an ASTM committee, Bowles says.

The light aircraft industry hopes AoA systems can reduce the most common cause of accidents - loss of control during the turn to final approach.

"The thought is to prevent some of those accidents the [US Federal Aviation Authority] has been trying to install an AOA system in more aircraft," Bowles says. "Icon is a little bit ahead of the others."

Source: Flight International