- The Norwegian military is trying to rescue a US CV-22 that's been stuck in a nature preserve since August.
- The US Air Force special operations aircraft suffered a clutch malfunction that is affecting the V-22 fleet.
Norwegian soldiers are working to recover a US Air Force CV-22 Osprey, the special operations variant of the tilt-rotor aircraft, that has been stuck in a remote Arctic nature preserve for more than a month, Norway's military said on Tuesday.
The military said in a statement that engineers are building an "improvised" road so they can bring the Osprey closer to shore, where it can be retrieved by a crane boat.
The aircraft has been sitting in the Stongodden nature preserve on the island of Senja in northern Norway since August 12, when it made a "controlled emergency landing" after a clutch malfunction, one of a series of such failures that led US Air Force Special Operations Command to ground its Ospreys from August 16 to September 2.
"We had one of these hard clutch engagement events. The aircrew put it down, and so we're in the midst of kind of a recovery process to get the airplane to a place where we can swap out the engines and gearboxes and all the things that need to be replaced," Lt. Gen. Jim Slife, head of Air Force Special Operations Command, said at an Air & Space Forces Association event on September 7.
"These things never seem to happen at airfields. They always seem to happen in Norwegian nature preserves above the Arctic Circle at the onset of winter," Slife added.
The recovery operation began on Monday at the port of Sørreisa, with materials and equipment — including a crane, bobcat, excavator, and wooden mats — being loaded on a barge for a five-hour journey to the nature preserve.
Norway's military said that, depending on weather and wind conditions, it hopes to move the Osprey from where it landed and lift it onto the crane boat — which is now waiting off the coast of the nature preserve — early next week.
A Norwegian military official confirmed to Insider last week that the Osprey made the emergency landing and the military was planning for its recovery. Photos provided to Insider at the time showed the location of the CV-22 and Norwegian soldiers preparing for its recovery.
Slife said on September 7 that hard clutch engagements are caused by "a slipping sprag clutch" in the input wheels on the Osprey's engines. Ospreys are designed to allow either engine to drive both propellers, and the slipping of the clutch triggers one engine to take over for the other.
"It just slips momentarily," Slife added. "When it engages again, it brings that load back to the original motor, and those large transient torque spikes exceed the limitations of the engines and the gearboxes."
The Osprey fleet has had 15 such incidents over the past 12 years or so — 11 affecting US Marine Corps Ospreys and four, including two in recent months, on Air Force Special Operations Command aircraft, Slife said.
"Each one of them results in kind a Christmas tree of caution lights in the cockpit and some pretty squirrelly flight-control input," Slife said, adding he was "really, really proud of our crews and the way they've been able to safely land."
The problem is known to be mechanical, but its root cause "has eluded us," Slife said, adding that his command's stand-down was meant to bring attention to the issue. The command has implemented operating restrictions to address the problem, including advising crews to use horizontal takeoffs rather than vertical takeoffs when possible.
Norway's military said the recovery project involved consultations with local environmental officials and with the US Air Force and would need to take into account the environmental impact in order to succeed.
Slife noted that troops involved might benefit from the experience. "It's provided a really great tactical problem for that unit, to figure out what to do with that airplane out in the middle of nature preserve with protected ferns and salamanders and things like that."