A serious incident in May in which the flight crew of an Airbus A330 operated by Air Berlin made a distress call to request an expedited landing in Munich due to pilot fatigue is being probed by Germany's air accident investigation bureau, BFU.

However, some observers have questioned whether the crew's "pan pan" urgency call was genuine or was instead motivated by a desire to highlight concerns over EASA's planned flight-time regulations.

The aircraft was approaching Munich airport after a flight from Palma de Mallorca on 5 May, when the pilots issued the distress call, asking air traffic control for permission to land without delay because, as the European Cockpit Association puts it, they felt "extremely fatigued".

Germany's air navigation service provider, DFS, tells Flightglobal that the crew made the call at 10:15 local time, when the aircraft was 5nm (9km) south of Oberpfaffenhofen airfield, on the western outskirts of Munich. Oberpfaffenhofen is located around 26nm southwest of the city's main airport. The aircraft landed safely 12min after the crew made the call.

BFU declines to provide any details about the investigation, beyond describing it as a serious incident. A preliminary factual report will be published as part of its next monthly information bulletin.

Ilja Schulz, president of the German pilots' union, Vereinigung Cockpit (VC), says he is unsurprised that people would question the motivation for the call.

"I think this incident shows very clearly that pilots are already flying fatigued today even under the existing rules," he says. The union has evidence to prove that today's rules go "far beyond the capabilities of the human body", he adds. VC recently conducted a survey in which 37% of participating pilots claimed to have unintenionally fallen asleep in the cockpit.

Schulz dismisses the suggestion that a pilot would issue a distress call for anything other than a genuine emergency. He points out that they would know the consequences for other aircraft in the vicinity and for air traffic control, not to mention their own careers.

Air Berlin says that there have been no previous incidents at the airline where flight crew departed from standard operating procedures due to pilot fatigue.

Source: Air Transport Intelligence news