Clutch problem in Osprey led to death of 5 Marines in 2022, Corps says

The investigation conducted by the Marine Corps concluded that a malfunctioning clutch in an MV-22 Osprey aircraft was responsible for the fatal crash in June 2022, claiming the lives of five Marines.

The office stated in a Friday statement that it has eliminated the risk of hard engagement clutch by 99% and the problem with the Ospreys prompted the joint V-22 program to ground an undisclosed number of tiltrotor aircraft in February.

The investigation conducted by the Marine Corps, which was released on Friday, unveiled that the clutch briefly disengages from its location linking the engine to the rotor gearbox of one propeller, and subsequently reconnects during forceful clutch engagements. This frequently results in significant harm to crucial parts of the aircraft with two engines, leading to sudden movements.

The Marine Corps had previously not specified the cause of the mishap that killed Lance Cpl. Evan A. Strickland, 19; Cpl. Seth D. Rasmuson, 21; Cpl. Nathan E. Carlson, 21; Capt. John J. Sax, 33; and Capt. Nicholas P. Losapio, 31, on June 8, 2022, in an Osprey accident.

In the eastern region of Southern California, close to El Centro, the aircraft crash prevention could have been carried out by the Marine maintenance team or these Marines. It was discovered by the command investigation conducted by the 3rd Marine Aircraft Wing that there was nothing present.

“A disastrous, unavoidable, and unexpected mechanical breakdown happened,” stated the joint program office on Friday.

However, the investigators relied on information from other sources, including statements from Marines who witnessed the aftermath and conducted a survey of the crash site. The analysis of the flight also included input from experienced Osprey pilots. Unfortunately, there was no recoverable data from the “crash-survivable” recorder due to the severe post-crash fire, and no one directly witnessed the crash itself.

The investigation discovered that the five crew members were proficient in their roles, and they did not have any significant physical health issues or major life pressures.

The crash took place at 12:14 p.M., However, the investigation reveals that the details of the moments leading up to and during the crash have been censored in the publicly disclosed version of the investigation. As per the inquiry, the plane took off at 8:40 a.M.

According to the investigation, the airplane was unable to maintain controlled flight, resulting in an imbalance in thrust that caused the right-hand proprotor to lose all power. The investigation found that the single engine and interconnect drive system, which is responsible for synchronizing the proprotors and transferring power to a rotor in the event of an engine failure, failed due to a problematic clutch engagement on both sides of the Osprey.

The Osprey crashed, resulting in the death of the five Marines on board.

According to the investigation, the conclusion was reached that there were no survivors when they flew past the crash site minutes later. Marines flying another Osprey as part of the same training flight soon observed smoke.

The sergeant in the other Osprey that investigators told couldn’t land near the crash site because their engine, which is supposed to protect from particles like sand, failed to separate air particles during landings.

The sergeant mentioned in the statement to investigators, which was enclosed in the investigation, “There was a significant risk of losing the engine during an attempted landing.”

When asked about the prevalence of the air engine’s separator particle, the joint office program did not provide any specific details, only stating that it continually evaluates and works on improvements.

Based on the inquiry, emergency personnel arrived at 1:45 p.M., Hindered by the secluded position of the crash site and the absence of accessible routes.

The Marine Corps stated that the mishap was caused by pilot error. In March 2022, four Marines lost their lives in a crash involving an Osprey in Norway. Following the five fatalities, another well-known incident involving the MV-22 Osprey occurred.

A month after the California tragedy, the Marine Corps’ safety division prepared a slide deck expressing confidence in the aircraft’s safety.

The presentation emphasized that the F-35B Lighting II, the F/A-18 Hornet, and the AV-8 Harrier have mishap rates below average compared to the Osprey.

“The slide deck states that our Ospreys have operated securely for numerous hours in various locations around the world. The significance of these two accidents is emphasized by the extensive number of hours our Ospreys have operated without incidents. However, it is important to note that no mishap is ever deemed acceptable.”

Prior to the June 2022 mishap in California, no one had died from a hard engagement clutch incident in an American V-22 investigation command.

In August 2022, the initial public indications of issues with the Osprey’s clutch arose when Air Force Special Operations Command temporarily halted the operations of its 52 Ospreys due to two intense clutch involvements within a span of six weeks.

In February, as per the office, the joint program office carried out a similar action for “a portion” of Ospreys throughout the services, which had experienced a rise in challenging clutch interactions.

According to Maj. Jim Stenger, a spokesperson for the Marine Corps, the office needed to replace the input quill assembly on Ospreys that had accumulated over 800 hours of flight time. This assembly includes the clutch and facilitates the engine’s connection to the gearboxes and rotors.

According to a statement on Friday by the Marine Corps, those substitutions decreased the chances of a difficult clutch connection by 99%.

Based on the command inquiry, the investigation observed that in the Osprey that had a crash in June 2022, the input quill assemblies on both sides had individually accumulated over 2,000 flight hours. This issue has occurred in Ospreys where the input quill assemblies have been in use for over 800 hours, although the underlying reason for abrupt clutch engagements remains unknown.

As per the statement provided by the service, the Marine Corps collaborated with Bell-Boeing, the manufacturer, to install a flight data recorder in all MV-22 Ospreys that is capable of enduring fire and heat. Additionally, they enhanced the drivetrain and developed a new input quill assembly.

According to Stenger, the joint V-22 office program has taken other steps to reduce hard clutch engagements, including extensive updates to simulators and software and risk assessments.

The Marine Corps’ statement has been included, and presentations regarding challenging clutch engagements will be conducted for pilots and aircrew, aiming to increase awareness among all Marine commands operating the Osprey aircraft.

“As we continue our quest to provide the safest lethal platforms to the women and men who fly them, we will never forget our loved ones, Lance Cpl. Evan A. Strickland, Cpl. Seth D. Rasmuson, Cpl. Nathan E. Carlson, Cpl. John J. Sax, Capt. Nicholas P. Losapio.”