Swiss aviator Riccardo Mortara and his crew have claimed the record for the fastest flight around the world in a 9,000 to 12,000kg aircraft. They had to add a 12th leg to their trip after plans to land in Keflavik, Iceland, were aborted due to a volcanic eruption.

Their aircraft, a 1980 Sabreliner 65, took off from Geneva at 06:12 UTC on Friday morning, flew east, and returned Sunday at 16:06 UTC, completing the 36,770km minimum distance in 57 hours 54 minutes. The average speed around the world was 647km/h.

Mortara says: "This is the first time a record has been set in this weight class with refuelling stops and beats pioneering pilot Steve Fossett's time of 67 hours and one minute which was achieved without stops in the state-of-the-art VirginFlyer in 2006."

A secondary target was to beat golfer Arnold Palmer's 1978 record of 57 hours 26 minutes, which he set in a Learjet 36 - a plane in a lighter weight category to Mortara's elderly Sabreliner.

Riccardo Mortara (62), co-captain Gabriel Mortara (28) and co-pilot Flavien Guderzo (26) flew from Geneva to Bahrain, then Colombo, Macau, Osaka, Petropavlovsk, Anchorage, Las Vegas and Montreal, before having to urgently change plans. Mortara says: "Our next intended destination had been Keflavik but the volcanic eruption resulted in all of Iceland's airports being shut down. Halfway there we were forced to return to Canada, refuelling in Goose Bay, Labrador, before re-calculating the Sabreliner's route. The eruption was the area's first in 176 years and added a huge element of suspense to the final day of the mission, and effectively cost it four hours."

With the aborted leg not counting towards the Federation Aeronautique Internationale (FAI) minimum distance, the previous Keflavik-Casablanca-Geneva plan was ditched in favour of Shannon, then Marrakech, and finally home to Geneva. The total distance travelled was 36,900km.

A key part of the 12-leg journey were the 'pitstops' with Jetex Flight Support one of the sponsors. Each time the crew landed, they urgently refuelled and took off again. Planned stops ranged between 28 minutes in Colombo and 55 minutes in Petropavlovsk. The unplanned stop in Goose Bay took 64 minutes.

Mortara says: "To complete this circumnavigation and establish a new record is a tremendous honour and the proudest moment of my career. Steve Fossett's time in this category of plane was a challenge to beat, but I was confident we could do so.

"In fact, we set our target a little higher, and aimed to beat Arnold Palmer's record in a lighter weight class. We came so close to achieving this, and would have done so by four hours were it not for the volcano in Iceland. Everything was going to plan until Keflavik. In the 35 years I have been flying across the Atlantic I have never heard of this airport closing. We did calculations on weather and risks like this for the last 40 years and the risk of a volcanic eruption that would disrupt our trip was not something we were expecting.

"We learned of this halfway to Keflavik from our previous refuelling stop in Montreal. We had two options: return to Canada, or divert to Shannon."

Marcel Meyer, FAI executive officer records, says the procedure is for the FAI to study a complete dossier of evidence submitted after a review by the national member before formally granting a world record.