Pilots’ ‘high risk flying’ led to fatal crash of Ju-52 plane

The vintage aircraft was flying from Locarno to Dübendorf in Canton Zurich. All 20 people on board lost their lives. © Keystone / Laurent Gillieron

Safety investigators have concluded that pilot error led to the accident involving the vintage aircraft that killed 20 people in eastern Switzerland in 2018. It was the country’s worst air tragedy since 2001.

The Swiss Transportation Safety Investigation Board’s final report, published on Thursday, found that the pilots steered the aircraft, which had been travelling at low altitude, without an alternative flight path and at dangerously low speed into a narrow valley southwest of Piz Segnas in Canton Graubunden.

The aircraft approached some turbulence – a phenomenon that can be expected when flying in the mountains. In a statementExternal link, the safety board wrote that “the high-risk manner of flying through these not unusual turbulences caused the pilots to lose control of the aircraft”. The plane was flying too low to rectify the situation and ultimately crashed almost vertically into the ground.

Everyone on board lost their lives – 17 passengers, two pilots, and a flight attendant. All of the passengers and crew members were Swiss, except for a couple from Austria, who were travelling with their son.

The safety board added that the “investigation does not establish blame or determine liability” but it did find that the pilots’ “high-risk flying” was a direct cause of the accident.

History of lax safety compliance

According to the report, other underlying factors contributed to the crash, including the fact that the centre of gravity of the aircraft was too far back. This was the result of poor flight preparation and a software error in the Ju-52. The report notes that while there were technical issues with the plane, this was not the cause of the accident.

“Errors on the part of air operator Ju-Air – as well as negligence by the supervisory authority, the Federal Office of Civil Aviation (FOCA) – contributed to the circumstances in which such an accident could occur,” wrote the safety board.

Ju-Air pilots had become accustomed to not following the rules for safe flight operations and took high risks when flying with passengers. The two pilots, aged 62 and 63, were described as highly experienced. They had piloted fighter jets as well as airliners during their decades of professional service.

The investigation also points to gaps in safety management processes and oversight. It found that Ju-Air failed to identify any significant risks and to prevent its pilots from breaking the rules. Various requirements for safe operations had also not been met for some time.

As a supervisory authority, the FOCA also failed to identify safety problems at Ju-Air. In August 2020, the civil aviation office said it was opening a separate investigation into “systematic aspects of supervision”.

The safety board has issued 15 recommendations to help identify and mitigate safety risks and strengthen oversight.

Tragic flight

The plane was a Junkers Ju-52 (affectionately known as ‘Tante Ju’ or ‘Auntie Ju’ in German), owned and operated by the Ju-Air company based in Dübendorf, which specialises in sightseeing flights using old military planes.

On the day of the crash it was on a flight from Locarno to Dübendorf in Canton Zurich. The crash was the worst accident in Swiss aviation since the 2001 crash of a Crossair plane at Bassersdorf, canton Zurich, in which 24 people died.

Flight operations resumed barely two weeks after the accident. However, in November 2018, the safety board banned all Ju-52 flights and in March 2019, Switzerland’s aviation agency revoked the commercial flight license for Ju-Air.