In-flight icing — Beechcraft King Air B200, inland NSW

Summary

An RFDS King Air B200 encountered severe structural icing at FL170 during a patient transfer flight. The crew activated all ice protection systems; however, airspeed degraded rapidly. The aircraft descended to escape the icing layer and land at Wilcannia under emergency conditions. All on board were uninjured.

Investigation Findings (4)

1. 01The BOM forecast for the route had indicated moderate icing, but the crew assessed conditions as acceptable.
2. 02Ice accumulation on the horizontal stabiliser exceeded the King Air's published limits before escape from the icing layer.
3. 03RFDS reviewed its icing weather assessment training and added specific guidance on tailplane icing.
4. 04ATSB published a safety advisory on tailplane icing in turboprop aircraft.