Transwede SE-DEC – 6. January 1987

Date  6. January 1987
Location Stockholm   Arlanda, Sweden
C/N 263
Model  Caravelle   10R
Airline Transwede   Airlines
Registration SE-DEC
Occupants  0/6 + 0/??
Aircraft history SE-DEC c/n 263 Caravelle 10R, made its first flight   on January 12th 1970 as F-WJAN. Originally ordered by Aviaco, the plane was   not taken up and leased to Sterling Airways as OY-SAZ on January 16th 1970.   It returned to Aérosptiale on October 27th 1971 and a months after it was   leased to the French Government until December 1971. It was then leased to LTU (Lufttransport-Unternehemen) on January 13th 1972 until January 19th 1976  when it returnned to Aérosptaiale as F-OCKH. It was leased once again – this   time to Air Europa and registered EC-CYI and was finally bought by Hispania  Lineas Aereas in April 1983. On April 29th it was sold to Bergen Aviation and registered LN-TEC and leased to Transwede Airways the same day and registered SE-DEC.
Accident description After a normal takeoff from Runway 08 at Stockholm-Arlanda, operating a charter flight, the aircraft pitched down from a height of 10m and the aircraft struck the runway, causing the landing gear to fail. The aircraft skidded off the runway and caught fire (which destroyed the FDR data). 21 passengers and 6 crew escaped uninjured. Evidently the pilot believed the aircraft had suffered a loss of control. Pre-flight inspection may have left unnoticed a layer of ice or snow on the stabilizer and all three hydraulic pressure accumulators for the flight control system were empty, possibly because of a leak, and this caused airlocks in the system and changed the pilot’s feel of elevator response. Because of several faults in the angle of attack transmitter (frozen, shortings),   signals were transmitted to the pitch corrector to reduce the nose-up attitude. This may have contributed to the pilot’s impression of lost longitudinal control although most probably the aircraft could have been fully controllable for a climb and return for landing. The aircraft was damaged beyond economical repair and was used by the fire service in Stockholm Arlanda until eventually scrapped over 20 years later.

The cause for this accident was ice: Due to heavy snow falls the stall warning sensor had been   frozen + clear ice on the wings