Flight History
On Saturday, 9 September 2017 at 20:08 local time, an ATR 72-212A aircraft, registration EC-KKQ, operated by Swiftair, took off from Alicante Airport on a scheduled domestic passenger flight to Madrid-Adolfo Suárez Airport. The crew consisted of 2 pilots and 2 cabin crew, with 22 passengers on board. The planned flight profile called for an initial climb segment to reporting point NARGO, followed by a cruise at FL170. The first officer was the pilot flying.
Incident Event
Eight minutes into the flight, the aircraft passed FL100 while climbing to FL170. The total air temperature reached 7°C. After climbing for 16 minutes, 8 of which had been in icing conditions, the aircraft suffered an uncommanded loss of altitude of 1661 ft lasting 33 seconds, accompanied by a series of uncommanded pitches and banks. The event occurred at 20:26 local time, 10 NM north of reporting point NARGO at FL170.
Landing
Following the event, the crew continued the flight to Madrid and executed an unstabilized, high-speed approach, touching down during the first third of the runway. All 26 persons on board were uninjured.
Probable Cause
The investigation determined that the probable cause of the loss of control in icing conditions was a deficient flight management by the crew and an inappropriate use of automation. The report contains four safety recommendations issued to Swiftair.