The Israeli Air Force cleared its fleet of heavy transport helicopters for flight on Sunday, over a month after one of the aircraft made a crash landing and caught fire due to a malfunction, the military said.
“Today, the air force’s fleet of Yasur helicopters gradually returned to flights, under a decision by air force commander Maj. Gen. Amikam Norkin,” the military said in a statement.
On November 26, the pilots of a Yasur heavy transport helicopter were forced to make an emergency landing in an open field in southern Israel following a technical failure in a gear connected to its left rotor, which caused a fire that destroyed the aircraft. The pilots’ quick actions — landing the helicopter in under a minute — were credited with allowing all 14 soldiers on board to escape unscathed.
Norkin ordered an investigation of the incident and grounded the aging fleet of helicopters, which have been in service in the Israeli Air Force since the 1960s.
The full probe into the malfunction has yet to be completed, the military said, but the initial findings provided sufficient information to allow the aircraft to return to service.
“The interim findings of the investigation provided a large amount of information on possible causes of the accident and the ways to safely return [the fleet] to flights, but has yet to definitively determine the cause of the malfunction in the Yasur helicopter,” the military said.
The Israel Defense Forces said it was in contact with the manufacturer of the Yasur, also known as the CH-53 Sea Stallion, and with the other air forces around the world that use the same model.
“[Norkin] stressed that these were only interim findings and ordered the completion of the investigation of the malfunction and instructed the fleet of Yasur helicopters to gradually return to training flights,” the IDF said.
According to the air force’s initial investigation, the fire that destroyed the helicopter originated in a gear that was part of a relay from the aircraft’s left motor, and not within the engine itself as originally suspected.
“Due to the high heat caused [by the gear], the relay caught fire, which led to the helicopter catching fire,” the military said in December.
The helicopter had been en route to a base in southern Israel for a training exercise. Eleven of the soldiers on board were members of the elite Shaldag commando unit, along with two pilots and a mechanic.
Three teams of firefighters were called to the scene to combat the blaze.
Israel’s fleet of Yasur heavy transport helicopters was purchased from the United States in the late 1960s. Though the aircraft have been upgraded and restored in the interim five decades, they are widely seen in the military as ready for retirement in favor of newer models.
In 2010, an Israel Defense Forces Yasur helicopter crashed during a joint exercise of the IAF and Romanian Air Force, killing the five people on board.
That crash was found to have apparently been caused by human error.
In 1997, two Yasur helicopters collided in the air while en route to locations in the country’s then-security zone in southern Lebanon. Seventy-three soldiers were killed in what was Israel’s most devastating air disaster.