Owners and operators of 765 Cessna Caravans in the USA will have to equip their aircraft with a Cessna-built low airspeed awareness system by 21 September under a new US Federal Aviation Administration airworthiness directive issued last week, writes John Croft.

FAA says the devices, estimated to cost about $6,500 per installation, are needed because the aircraft's legacy aural stall warning system does not give pilots sufficient warning of an incipient wing stall in all icing conditions. The agency worked with Cessna and the US Regional Air Cargo Carriers Association to develop the solution in response to a number of icing-related Caravan accidents since 1990 in the USA, Canada and elsewhere.

Cessna describes the system as a pitot-static switch that activates when the propeller heater is turned on and provides an audible tone and indicator light to alert the pilot of low speeds.

Source: Flight International