Call to Air Operators for Robust Risk Analyses before Operating Flights to Cold-weather Countries

The twinjet had remained parked on the apron for approximately three days in freezing temperatures. Because suitable heaters were not available at the airport, the airplane had to be warmed-up by running the engines. During the start-up procedure the low brake pressure caution light illuminated and the system circuit breaker tripped. The crew reset the circuit breaker and continued the warm-up run. While power was increased asymmetrically for systems testing with the main landing gear unchocked, the airplane moved forward. The brakes failed to operate, and the airplane eventually struck a lamp post.

“Investigations have often highlighted the fact that several factors may come together and eventually lead to an incident or an accident. This particular investigation concluded that the air operator’s safety review had not adequately addressed Finnish winter conditions. The crew was somewhat inattentive during the external inspection of the airplane, and they were not advised of missing main landing gear chocks. The brake system caution light remained illuminated during the warm-up run but the crew did not respond to the indication. The circuit breaker tripped repeatedly, only to be reset each time by the crew. A circuit breaker is an electrical safety device that operates like a fuse but does not need to be replaced after tripping. Finally, pneumatic emergency brakes were not applied, although sufficient time was available. This time, luckily, the accident resulted only in damage to equipment”, says investigator-in-charge Janne Kotiranta.

The SIAF recommends that air operators improve their safety review procedures. The authority also recommends that ground handling companies adhere more closely to their prescribed rules and practices.

Link to summary and investigation report

Further information:
Investigator-in-charge Janne Kotiranta, tel. +358 2951 50703

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