The Air Force Special Operations Command has grounded all 52 of its CV-22 Ospreys because of an issue with the clutch that controls the distribution of power between the engines and rotors. The AFSOC says there have been two incidents in the last six weeks making a total of four in the last five years in which the clutches slipped and caused asymmetrical power distribution to the rotors. None of the aircraft involved crashed, but there have been some hairy moments and the Air Force credits the “skill and professionalism of our Air Commandos who operate the CV-22.”
When the clutches slip, they sometimes reengage, which throws power back the other way, and “if the aircrew were unable to control the aircraft when the incident occurs, it could result in loss of control and uncontrolled landing of the aircraft,” Lt. Col. Becky Heyse told Breaking Defense. “The safety of our Airmen is of the utmost importance, therefore no AFSOC CV-22s will fly until we will determine the cause of the hard clutch engagements and risk control measures are put in place.” It’s not clear how long the tiltrotors will be grounded. The Navy and Marines operate hundreds of the aircraft but there has been no similar announcement from those branches.
Uncontrolled landing of the aircraft? Is that followed by an unscheduled disassembly?
I would imagine; the thing cannot land in full “airplane mode”; the rotors are too big.
Sort-of. The rotor blades have a designed-in weak spot to break away where they will contact the ground if the machine ever needs to land in “airplane mode”. So it can be landed safely in airplane mode, but not without at least minor damage.
Have they got over the noise problems? Early reports I heard were that the troops on the ground could hear them when they were 20 km away which rather spoilt the quick insertion missions they were trying.
I don’t care how much redundancy you build into a design, Murphy always manages to find a place to pop up. In my helicopter, I’d pretty-much have to grossly exceed max rotor RPM and sling a blade off before I couldn’t auto-rotate down from a mechanical. Not so for all these new powered-lift designs, like the Opener that flew at Airventure.