Icing event, 130 km north-west Brisbane, Queensland, on 10 February 2005, VH-SBI, de Havilland Canada DHC-8-315

On 10 February 2005, a de-Havilland Canada Dash 8-315 aircraft, registered VH-SBI, was enroute from Gladstone to Brisbane Airport, Qld, on a regular public transport service. The aircraft was operating in instrument meteorological conditions and had accumulated ice on the airframe, wings, and propellers.

During the climb out of Gladstone, the anti-ice and de-icing equipment were selected ON in response to the inclement weather. While in the cruise at flight level 210, air traffic control (ATC) instructed the crew to 'set course Maleny time 24'. The flight crew acknowledged ATC and reduced power, in order to make good the instruction.

When the flight crew reduced speed in order to comply with the ATC instruction, they noticed a number of indications that they suspected were as a result of ice accretion. After initially increasing power, the crew again reduced power in response to an engine temperature warning. That power reduction was accompanied by the activation of the aircraft's stick shaker warning. The crew recovered the aircraft and landed at Brisbane without further incident.

Following a company investigation, the operator provided additional training for the flight crew and amended the company operations manual to specifically address the minimum speeds for operations in and out of icing conditions.