Having been grounded for just over two weeks, US Air Force Special Operations Command (AFSOC) has cleared its 52-strong fleet of Bell Boeing CV-22B Ospreys to fly again, but one example remains trapped on an island in Norway after the tiltrotor was forced to make an emergency landing there on August 12, 2022.
The grounding order was formally lifted on September 2, two weeks after the AFSOC commander, Lt Gen Jim Slife, directed a safety stand down of the US Air Force’s (USAF’s) CV-22B fleet – which is used to support US Special Operations Forces (SOF) missions across the globe. Beginning on August 16, this grounding order was imposed as a safety measure after two incidents of hard clutch engagement were reported during CV-22B flight operations in the previous six weeks.
When the grounding order was imposed, Col Rebecca Heyse – AFSOC Public Affairs Director – told Key.Aero that there had only been two other such hard clutch engagement incidents since 2017. Hard clutch engagements occur when the clutch that connects the rotor gear box to the engine slips before catching hard and causing the aircraft in question to lurch. While no one was injured as a result of these incidents, the two CV-22Bs had to immediately make emergency landings.
One of the two CV-22Bs to suffer from this issue was forced to make an emergency landing while deployed on operations in Norway on August 12. The aircraft (serial 10-0053), assigned to the 7th Special Operations Squadron (SOS) ‘Aircommandos’ – a component of the USAF’s 352nd Special Operations Wing (SOW) at RAF Mildenhall in Suffolk, UK – was forced to land in the Stongodden nature reserve, which is located on the island of Senja in Troms, Norway.
As reported by Scramble on September 2, the Osprey remains stuck in the island’s nature reserve and on-site repairs are said to be impossible. Prospective recovery operations will also be rather challenging, given the vulnerable environment that the CV-22B currently resides in and the risk of damaging the terrain. However, the Norwegian Armed Forces are investigating several options for recovering the trapped Osprey in liaison with US authorities.
That being said, there are no easy solutions in its recovery. The Osprey cannot be dismantled on-site as it would become unbalanced and could tip over – causing more damage to both the aircraft and the surrounding terrain. The Norwegian Armed Forces have suggested laying down mats on the terrain to enable personnel and equipment to approach the CV-22B without damaging the nature reserve.
It is also considering the possibility of lifting the aircraft onto a transport barge using a crane, but due to the shallow coast in the area, getting the barge close enough would be problematic and a 70m-long crane arm would be required. Another challenge for recovery teams is Norway’s turbulent and sometimes hostile climate, which can change rapidly and risk delays in the Osprey’s recovery – especially as the Norwegian winter draws closer. On top of these environmental challenges, any such recovery operation is also expected to be very expensive.
While AFSOC has yet to identify the cause of the issue, it has developed new mitigation guidelines to deal with the hard clutch engagement issues in the short-term and continues working to identify and address the problem. As described by Air Force Magazine, these guidelines include modifying take-off techniques; including squadron leaders in risk mitigation discussions for operations at higher risk of such incidents; incorporating and modifying scenarios of hard clutch engagement in simulator training and increased training for marginal flight power and aborted take-offs.
In addition, AFSOC is considering a medium-term solution of replacing specific drivetrain components after they reach a certain number of flight hours. However, in the long-term, the command intends to identify the cause of the hard clutch engagement problem and develop a materiel solution for the issue.