Vueling Airlines A320 Navigation Failure Incident Near Zurich (EC-HTD)

Incident Overview and Aircraft Details On September 20, 2017, at 18:44:58 UTC, a Vueling Airlines Airbus A320-214, registration EC-HTD, experienced a serious incident while climbing at Flight Level 75, approximately 8 nautical miles west of Zurich. The aircraft, operated by Vueling Airlines S.A. of Barcelona, Spain, was on a scheduled IFR flight from Zurich (LSZH) to Barcelona (LEBL). The incident was classified as a failure of navigation instruments. The flight crew consisted of an Italian captain (born 1963) and a Spanish first officer (born 1975), both holding EASA ATPL(A) licenses. The captain had 18,120 total flight hours, while the first officer had 5,071 total flight hours. ## Sequence of Events The aircraft departed Zurich runway 28 at 18:41:23 UTC under flight plan VY6249. Shortly after takeoff, the crew received clearance to climb to Flight Level 120. At 18:44:58 UTC, during a frequency change instruction from Zurich Radar, the autopilot and autothrust systems automatically disengaged. A master warning and a repeated 'cavalry charge' tone sounded for 21 seconds. The captain informed air traffic control of a 'small issue' and requested a brief delay. The crew subsequently performed a reset of the Flight Management Guidance Computers (FMGC) by pulling the circuit breakers for both units. ## Crew Actions and Communication Following the FMGC reset, the crew reported that both MCDUs and flight directors were off. The captain requested heading instructions from air traffic control. At 18:48:40 UTC, the captain indicated a desire to return to Zurich due to a lack of navigation indication. Air traffic control vectored the aircraft back to Zurich with a left turn to heading 050 degrees. The crew confirmed they could not follow an instrument approach and requested a visual approach. The captain noted a 'double FMGC failure' and 'dual MCDU' loss during discussions with the first officer. ## Approach and Landing Air traffic control provided radar vectors for a visual approach to runway 14. The aircraft descended through Flight Levels 150, 130, 110, and 70. At 19:01:16 UTC, the crew was cleared to descend to 6,000 feet with a QNH of 1022 hPa. The crew configured the aircraft at 4,000 feet. At 19:07:36 UTC, the first officer reported the runway in sight. The aircraft landed on runway 14 at 19:13:23 UTC. During rollout, the Enhanced Ground Proximity Warning System (EGPWS) issued eight 'terrain ahead, pull up!' warnings. The aircraft then taxied to the stand, and passengers disembarked normally. ## Meteorological Conditions The approach was conducted under clear skies and light wind conditions. The valid METAR for Zurich at 18:50 UTC was: 201850Z VRB01KT CAVOK 09/07 Q1022 NOSIG, indicating variable winds at 1 knot, clear skies, a temperature of 9°C, a dew point of 7°C, and a QNH of 1022 hPa.