An unidentified defense official told Military.com that the pentagon will be grounding an unspecified number of V22-Osprey helicopters due to a faulty “input quill assembly” that connects the V-22’s engines to its gearbox. The part can cause a “hard clutch engagement” when it fails which can cause pilots to lose full control of the engines which prompts an emergency landing. The unidentified official wouldn’t disclose how many of the nearly 400 V22-Ospreys will be grounded, but they did say that there’s a certain number of flight hours that qualifies the aircraft for grounding. The exact number of flight hours was also undisclosed. Two V22s crashed last year, one in Norway and the other in California. Five Marines were killed in each of those crashes. The Pentagon has not said whether or not the crashes were linked to this hard clutch engagement, but the issue has been linked to at least four incidents since 2017.