Swiss aviation authorities have explained why they refused overfly permission to an Air Malta flight carrying the prime minister, confirming that the decision stemmed from an error in the flight plan submitted by the airline. They also pointed out that the London-bound flight was never supposed to enter Swiss airspace anyway.

Their version of events tallies with the one given by Air Malta and sheds more light on the circumstances surrounding the incident on January 2.

Air Malta flight KM100 was on its way to Heathrow but was forced to circle over  the north of Italy when it was turned back by French air traffic controllers. Italian controllers then re-directed it to Switzerland.

A spokesman for the Swiss Federal Office of Civil Aviation said that since the flight was never meant to fly over Switzerland, Swiss controllers never expected it.

Taken by surprise and with the flight just minutes away, the Zurich controllers called the Swiss Air Force and then, based on the scarce information and considering the French decision, decided to do likewise.

It transpired that the flight plan submitted by Air Malta had been given the special handling code ‘State’ instead of ‘Head’, the spokesman said. “This converted the regular commercial flight to an official State flight, which required special authorizations and prior diplomatic clearances.”   

The Zurich controllers also asked their Geneva counterparts to check with France about their refusal and temporarily guided the aircraft during this period “on a western route outside Switzerland”.

With the issue finally sorted, France accepted the flight and it was able to resume its planned route.