Operators of Cessna Caravan single-turboprop utility aircraft are required to make a hands-on check of the wing before take-off when icing is possible under a new airworthiness directive (AD) issued by the US Federal Aviation Administration. The AD results from several icing-related accidents and incidents involving Cessna 208 and 208B Caravans, the FAA says.
In addition to a visual check for icing, the AD requires a tactile check of the wing leading edge and upper surface up to 0.7m (2ft) behind the deicing boot, as well as the horizontal tail leading-edge and propeller blades. The Caravan is a high-wing aircraft. Conditions in which checks are required include air temperatures below 5°C (41°F) and the presence of visible moisture.
Tactile checks were recommended by the US National Transportation Safety Board in December last year, after a review of 26 icing-related accidents and incidents from 1987 to 2003 involving the Caravan. The AD cites six accidents in the previous two icing seasons and "nine events in the past few months". The FAA says icing accident rates for the Caravan are higher than the average for all aircraft.
GRAHAM WARWICK/WASHINGTON DC
Source: Flight International