Viking 400 Becomes SafeFlight AoA Test Bed

Indicator offers pilots additional awareness of stall margins.

Safe Flight
Safe Flight is testing its digital AoA indicator in a Viking 400 Twin turboprop.Safe Flight

Safe Flight Instrument Corporation has begun testing its digital angle of attack indicator using a Viking 400 Twin turboprop as the testbed. The AoA provides pilots with increased awareness of the margin above stall, as well as trend information approaching a stall, both important elements as an aircraft slows during final approach. The system also delivers an easy-to-interpret visual indication of best climb speed aiding the pilot of utility STOL aircraft, such as the Series 400 Twin Otter, during backcountry and unimproved runway operations.

Safe Flight’s AoA system is comprised of a wing lift transducer, computer and indexer. The indexer is the in-cockpit display that delivers heads-up like guidance to the pilot. The company said, “All factors which affect angle of attack are accounted for in the Safe Flight system, including flap and gear changes, wind gusts, ground effect and weight distribution, providing an additional measure of safety in the extreme operating conditions for which the Twin Otter’s performance has become renowned.”

The Safe Flight system provides ARINC outputs to drive low airspeed awareness (“LAA”) and AoA displays on the Honeywell Apex primary flight displays. Safe Flight’s wing lift transducer is a heated, leading-edge monitor device and is Flight into Known Icing capable. Safe Flight’s NBAA booth is N1727.