Zurich: Two pilots died when a Swiss military helicopter crashed in the Alps on Wednesday, prompting the air force to ground its fleet of Super Pumas while it investigates what caused the accident.
Another crew member was injured when the Airbus helicopter went down at the Gotthard Pass after dropping off French and Swiss personnel taking part in an international inspection mission, Air Force Commander Aldo Schellenberg said.
"As we don't have any indications of the cause of the accident I have ordered as a precautionary measure the suspension of all Super Puma... flights until further notice," Schellenberg told a news conference in Bern.
Defence ministry officials did not confirm media reports citing eyewitness accounts that the helicopter had touched a power pylon before it went down. They said any role the weather might have played was still under investigation.
Swiss media showed pictures of smoke billowing from flaming wreckage under blue skies.
The European Aviation Safety Authority grounded all Super Puma helicopters for commercial use in June following the discovery of metal fatigue in the gearbox of an H225 model that crashed in Norway in late April, killing 13.
Following a series of incidents in the North Sea, analysts and industry executives say questions have been growing over the future of at least the civil version of the Super Puma helicopter, a workhorse of the offshore oil industry.
Airbus Helicopters has said it has no plans to scrap the model.
Wednesday's incident was the latest in a series of Swiss military crashes. A Swiss Air Force F/A 18 fighter jet slammed into a mountainside this month, killing the pilot.
That crash was the third by an F/A 18 in the past three years. A Swiss F-5E air demonstration fighter jet collided with another plane and crashed into a pond in the northern Netherlands ahead of an air show in June.
"I am infinitely sad that we again have victims to mourn," Schellenberg told reporters, expressing regrets to French authorities about the crash, which four of its officers narrowly avoided.