v-22 osprey
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list of v-22 osprey growing pain (deaths)
hydralic virus
gearbox flaw
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v-22 osprey Tilt-Rotor aircraft the window maker (tombstone effect, tombstone technology development method (TTDM))
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List of Osprey v-22 manufacturing issues:
- manufacturing issues, like the persistent issue with the Osprey’s gearbox that can cause its clutch to dangerously slip.
- The rotors generate so much wind, they kick up dust and debris both into the engines and into the air, obscuring the pilot’s visibility.
- The rotors often damage carrier bases and tarmacs during takeoffs and landings because of the high temperatures they produce.
- Problems like these make the Osprey expensive to operate and maintain.
- These issues may be traced back to 1999, when the program waived a number of operational tests because the Osprey was unable to meet certain requirements — an unacceptable workaround.
- “You shouldn’t be able to fudge program requirements when the prototype isn’t up to snuff,”
- “The military tends to know about design flaws long before they actually fix them," Julia explained. “I think the services would like to say instead, ‘Look, the Osprey is a complicated aircraft, and you have to get in a lot of flight hours to know how to mitigate these issues.’”
- “But it’s more of a reflection of the program itself than the pilots that these issues are resurfacing over the course of decades.”
Crash Course: V-22 Osprey
The V-22 Osprey has been touted as the aircraft of the future. But its troubling track record of crashes should give us all pause.
Sep 28, 2023 |
Spurthi Kontham
Crash Course: V-22 Osprey
Last month, a V-22 Osprey crashed during a routine training exercise in Australia with 23 people onboard. Three U.S. Marines died in the crash, and five others were rushed to the hospital in critical condition. Lamentably, the tragedy sounds all too familiar to those who know of the Osprey’s history. Just last year, five Marines died in an Osprey crash in California, also during a training exercise. Over the years, there have been over a dozen Osprey crashes that have left over 50 people dead. But these crashes are just the beginning of the Osprey’s issues: The aircraft’s new-age design has ushered in a host of unprecedented challenges.
The Osprey’s touted as the aircraft of the future — and not just the military’s future. But given its track record, that could be a bad thing. Where did things go wrong with the Osprey, and how can we make sure the safety of our troops isn’t jeopardized when flying them?
In this edition:
A helicopter-plane hybrid
Unprecedented design, unprecedented problems
Who’s at fault?
Looking above and ahead
To better understand the V-22 Osprey’s history, I talked to POGO Center for Defense Information Analyst Julia Gledhill, who recently wrote an analysis on the matter for Responsible Statecraft.
Read Now: Why they call the Osprey the ‘widow maker’
But first, some context.
Understanding the Osprey’s design is fundamental to understanding the issues that plague the program.
The Osprey is a cross between a helicopter and a plane, combining the former’s vertical takeoff and landing capabilities with the latter’s ability to cover long distances and carry more people (up to 24) faster. It does this with the help of rotating blades (rotors) on each of its wings. This type of aircraft is called a tiltrotor, and the Osprey is the first of its kind in the U.S. military’s arsenal.
It’s believed that the need for the Osprey was born out of the failed Operation Eagle Claw. “The Iran hostage crisis revealed that there was a need for high-capacity, long-range aircraft that could still move with the agility of a helicopter,” Julia explained.
Full-scale development of the aircraft began in 1986. The Osprey is now most used by the United States Marine Corps (USMC), who, among other uses, employ the aircraft to transport troops and equipment long distances from sea bases. The agility and maneuverability of the Osprey has become representative of “a whole new way of war,” according to the USMC force design plans.
Long-term problems
But the Osprey’s shown concerning signs from the very start. The craft spent an unusually long time in development. In that period, the cost of the tiltrotor skyrocketed way past what was projected, ballooning by over 200%.
By the very nature of being the first of its kind, the aircraft ran into some previously unencountered problems. The rotors generate so much wind, they kick up dust and debris both into the engines and into the air, obscuring the pilot’s visibility. The rotors often damage carrier bases and tarmacs during takeoffs and landings because of the high temperatures they produce. Problems like these make the Osprey expensive to operate and maintain. They also keep the aircraft from performing: For 10 years straight, the Osprey fleet wasn’t deemed capable of carrying out its designated missions.
- The rotors generate so much wind, they kick up dust and debris both into the engines and into the air, obscuring the pilot’s visibility.
- The rotors often damage carrier bases and tarmacs during takeoffs and landings because of the high temperatures they produce.
- Problems like these make the Osprey expensive to operate and maintain.
These issues may be traced back, frustratingly, to 1999, when the program waived a number of operational tests because the Osprey was unable to meet certain requirements — an unacceptable workaround. “You shouldn’t be able to fudge program requirements when the prototype isn’t up to snuff,” Julia said.
- These issues may be traced back to 1999, when the program waived a number of operational tests because the Osprey was unable to meet certain requirements — an unacceptable workaround.
- “You shouldn’t be able to fudge program requirements when the prototype isn’t up to snuff,”
The blame game
Because it is a new design, operating the Osprey has proved to be a learning process for everyone: pilots, maintenance crew, and manufacturers alike. The Osprey has been called challenging and “unforgiving” to fly.
In her new analysis, Julia pointed out the striking fact that many of the documented Osprey crashes occurred during pilot training. In their training, pilots are taught not just how to fly the craft but to be aware of and avoid existing manufacturing issues, like the persistent issue with the Osprey’s gearbox that can cause its clutch to dangerously slip. The crash that occurred in California last year, which claimed five Marines’ lives, occurred because of this very issue. An investigation into the matter found that there was nothing pilots could’ve done to prevent the mechanical failure.
List of Osprey v-22 manufacturing issues:
manufacturing issues, like the persistent issue with the Osprey’s gearbox that can cause its clutch to dangerously slip.
“The military tends to know about design flaws long before they actually fix them," Julia explained. “I think the services would like to say instead, ‘Look, the Osprey is a complicated aircraft, and you have to get in a lot of flight hours to know how to mitigate these issues.’”
She continued, “But it’s more of a reflection of the program itself than the pilots that these issues are resurfacing over the course of decades.”
Protecting the future
The V-22 Osprey has been touted as the aircraft that can usher not just military aircraft but civilian airliners into the future. It’s the first of its kind, but it is unlikely to be the last.
The Army is currently preparing to launch the V-280 Valor program: A new class of tiltrotor aircraft that will replace the more reliable and iconic fleet of Black Hawk helicopters, which have served a variety of functions in the military for over 40 years.
But with questions about tiltrotors’ effectiveness and safety still up in the air, it’s important as ever that the Osprey’s issues are investigated now, for the sake of our troops’ safety and the future of flight as a whole.
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- CH-53E helicopter (more dangerous than osprey v-22, why?)
- Osprey generates excessive wind on the ground.
- rotor downwash proved problematic in Iraq, during the Osprey’s first deployment in 2007.
- the pilots couldn’t see anything!
- The Marine Corps ended up tasking CH-53E pilots with scouting out landing zones for the Ospreys — largely defeating the purpose of a helicopter/airplane hybrid.
- The issue of the Osprey’s rotor blast persists.
- impair pilot visibility
- it literally kicks soil into the aircraft’s engines.
- redesign may not even “correct long-standing problems with the V-22.”
- Mark Thompson
- mechanical challenges
- UH-1 huey
- AH-1 cobra
- rotor issues
- rotor separated from the aircraft
- “killed hundreds of troops between 1967 and 1983.”
- unreliability and expensive maintenance needs.
Why they call the Osprey the 'widow maker'
After the hybrid craft has been linked to a series deaths, one wonders why it's taken so long to face the facts.
ANALYSIS | MILITARY INDUSTRIAL COMPLEX
Military Industrial Complex Pentagon Budget
JULIA GLEDHILL
SEP 21, 2023
The V-22 Osprey flies like a bird and hovers like a bee.
Furnished with rotors at the end of each wing, the aircraft takes off and lands like a helicopter but relies on its fixed wings to go the distance during flight. For this reason, some consider the Osprey the best of both worlds in aviation — others call it “the widow maker.”
Just a few weeks ago, three Marines died in an Osprey crash during a training exercise in Australia, bringing total fatalities involving the Osprey to over 50. And while there are certainly more dangerous aircraft out there (take the CH-53E helicopter, for example), what’s striking about the Osprey is that since the aircraft became operational in 2007, most of the fatalities involving the aircraft have happened during training exercises, not active operations.
- CH-53E helicopter (more dangerous than osprey v-22, why?)
Still, the Osprey isn’t historically reliable when it comes to combat readiness. In fact, the program missed the boat on meeting its reliability rate goals in every year from 2011 to 2021 — despite taking its first flight in 1989. The aircraft didn’t make its combat debut until 2007, having missed deployment to “Bosnia in 1995, Afghanistan in 2001, and Iraq in 2003.” And for good reason — during the testing phase, the aircraft experienced four crashes resulting in 30 fatalities.
Since then, the program has grappled with persistent design flaws, significantly increasing the program’s costs. From 1986 to 2007 alone, the program’s research, development, testing, and evaluation costs ballooned by over 200 percent.
With rotors situated atop wings like tree branches, the Osprey requires serious horsepower to get moving. There are two engines to propel the rotors, lifting the aircraft for vertical takeoff and then thrusting the Osprey forward during flight. So as you can imagine with not one, but two rotors, the Osprey generates excessive wind on the ground.
- Osprey generates excessive wind on the ground.
- rotor downwash proved problematic in Iraq, during the Osprey’s first deployment in 2007.
- the pilots couldn’t see anything!
- The Marine Corps ended up tasking CH-53E pilots with scouting out landing zones for the Ospreys — largely defeating the purpose of a helicopter/airplane hybrid.
- The issue of the Osprey’s rotor blast persists.
- impair pilot visibility
- it literally kicks soil into the aircraft’s engines.
- redesign may not even “correct long-standing problems with the V-22.”
Its rotor downwash proved problematic in Iraq, during the Osprey’s first deployment in 2007. In a desert environment, the pilots couldn’t see anything! The Marine Corps ended up tasking CH-53E pilots with scouting out landing zones for the Ospreys — largely defeating the purpose of a helicopter/airplane hybrid.
The issue of the Osprey’s rotor blast persists. Not only does it impair pilot visibility, but it literally kicks soil into the aircraft’s engines. In 2019, the Department of Defense Inspector General (IG) reported that the Osprey remains at risk of engine failure. Over nine years of attempts to redesign the Navy version of the aircraft and to prevent engine ingestion of natural materials have failed. The IG went so far as to state that redesign may not even “correct long-standing problems with the V-22.”
- Department of Defense Inspector General (IG) reported
on osprey v-22
Besides the risks associated with the Osprey’s rotor blast, the aircraft struggles with a troublesome gearbox. The faulty device can cause the engine clutch to slip, which unintentionally disengages one of the aircraft’s proprotors — dually functioning as a rotor and propellor. A malfunctioning proprotor (even if only disengaged for a matter of moments) sends a lurch through the aircraft, throwing it off balance and causing it to nosedive.
- gearbox : cause the engine clutch to slip
- A malfunctioning proprotor (even if only disengaged for a matter of moments) sends a lurch through the aircraft, throwing it off balance and causing it to nosedive.
That’s what happened last summer when five Marines died in an Osprey crash in California. An investigation into the crash recently revealed that there was nothing pilots could have done to prevent or respond to the issue. And while investigations into other recent Osprey crashes have not yet been released, it appears the gearbox issue played a role in several recent Osprey “mishaps.” The Air Force grounded its V-22 fleet last summer because of the issue, and the Marine Corps and Navy have since followed suit, grounding an undisclosed number of Ospreys.
The military has known about the gearbox and clutch problem since 2010, when an Air Force Osprey crash killed four people and injured many others. But as my colleague Mark Thompson has pointed out, this particular mechanical challenge greatly resembles those of older helicopters — the 67 UH-1 Huey and AH-1 Cobra in particular — which faced rotor issues that “killed hundreds of troops between 1967 and 1983.”
- Mark Thompson
- mechanical challenges
- UH-1 huey
- AH-1 cobra
- rotor issues
- rotor separated from the aircraft
- “killed hundreds of troops between 1967 and 1983.”
In the case of those aircraft, the rotors didn’t just disengage, but in some cases separated from the aircraft entirely. With that terrifying imagery in mind, imagine watching the military blame a crash on pilots no longer around to defend themselves.
Another through line between the Osprey, the Huey, the Cobra, and even the CH-53E is the tendency for the services to attribute mishaps to pilot error. Thompson notes that, in the 1980s, the Army produced a film to train and educate aviators on how to avoid the Cobra and Huey’s rotor issues before eventually grounding the Huey and replacing parts in both aircraft to fix the issue. The tradition continues with the Marine Corps repeatedly blaming pilots for CH-53E and Osprey crashes, the latter of which prompted the late Walter Jones — who represented North Carolina’s 3rd congressional district — to lead a 14-year-long crusade to clear the names of two pilots who died in a 2000 crash.
Jones was ultimately successful in spite of the squadron commanders’ mischaracterization of the V-22’s true performance through incomplete and/or inaccurate readiness reports.
Time will tell the true causes of the most recent Osprey crashes, but if history is any indication, there will be several contributing factors. The question now is how investigators will weigh them.
Regardless, the effectiveness of the Osprey is more critical to investigate now than ever as the Army prepares to launch the V-280 Valor program, which is set to eventually replace the Army’s fleet of Black Hawk helicopters.
This new program, which could cost up to $70 billion in its lifetime, will supposedly help the Army prepare for a potential future war in the Pacific. There, issues of range could be a serious factor, so the V-280 Valor will employ a similar design as the V-22. But that means it will likely face the same sort of challenges and tradeoffs as the Osprey, like unreliability and expensive maintenance needs.
- unreliability and expensive maintenance needs.
Julia Gledhill
Julia Gledhill is an analyst in the Center for Defense Information at the Project on Government Oversight. Before joining POGO, she was a foreign policy associate at the Friends Committee on National Legislation.
The views expressed by authors on Responsible Statecraft do not necessarily reflect those of the Quincy Institute or its associates.
SEP 21, 2023
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gearbox flaw (osprey v-22)
Known V-22 Gearbox Problem Caused Fatal June 2022 Crash
Brian Everstine July 21, 2023
The U.S. Marine Corps has since 2010 known of a critical safety issue on its V-22 Osprey fleet—a gearbox flaw that can cause the tiltrotor’s clutch to slip, severely impacting the safety of flight.
For years, the Corps says it has trained its crews to be aware of and work around the issue. While the Air Force grounded its V-22 fleet last year because of the issue, the USMC kept flying, saying it is confident in the safety of its aircraft.
On June 8, 2022, a hard clutch engagement (HCE) hit a V-22 as it flew over the deserts of Southern California, causing the Osprey to violently crash and killing all five on board. Despite USMC claims that its crews could work around the issue, an investigation released July 21 states there was nothing the expert pilots could do. They could not have known that the problem was going to happen, and they did not have time to react.
Aviation Week reporting shows the newly released investigation was one of at least four such gearbox problems that occurred in serious crashes of both Marine Corps and U.S. Air Force V-22s last year. While the new accident investigation board report into the June 2022 incident states the HCE was the primarily cause of that crash, an investigation into another 2022 fatal MV-22 crash in Norway states a gearbox problem did occur but blamed that mishap on pilot error.
For the U.S. Air Force, at least two proprotor gearbox problems forced down V-22s, according to information on the Class A mishaps by Aviation Week---incidents defined as causing at least $2.5 million in damage or severe injuries or deaths. One high-profile incident in August 2022 in Norway prompted the Air Force to stand down its operations. This came after another incident on May 17, 2022. Investigations into these incidents have not been released, and there were multiple other similar incidents, including another USAF CV-22 forced to land on July 8, 2022, and an MV-22B experienced an engine fire while landing in October 2022.
- two proprotor gearbox problems
While the Air Force stood down operations and was the first to commit to retrofitting the input quill assemblies of its fleet, the Marine Corps and Navy kept flying after the June 2022 crash in California.
- input quill assemblies
The mishap crew was from the “Purple Foxes” of Marine Medium Tiltrotor Squadron 364 (VMM-364)---Capt. Nicholas P. Losapio, Capt. John J. Sax, Cpl. Nathan E. Carlson, Cpl. Seth D. Rasmuson and Lance Cpl. Evan A. Strickland.
According to the accident investigation board (AIB) report, the Osprey was one of two flying near Glamis, California, for a live-fire tail gun training mission from Camp Pendleton. After the third pass, the V-22 crew reported via radio it had “hot boxes,” meaning the aircraft’s gearboxes were running at a high temperature. The crew then climbed to a higher altitude to cool the gearboxes. After coming down for another weapons pass, the Osprey’s wingman lost visual of the V-22 during a turn because of the angle of bank. Seven seconds after the last radar contact, the V-22 crashed.
- “hot boxes,” meaning the aircraft’s gearboxes were running at a high temperature.
- hard clutch engagement (HCE)
The AIB states the cause of the crash was a dual HCE, creating a single engine and interconnect drive system failure. This caused a “catastrophic loss of thrust” on the right proprotor, creating an unrecoverable departure from controlled flight.
“It is clear from the investigation that there was no error on the part of the pilots and aircrew and nothing they could have done to anticipate or prevent this mishap,” Headquarters Marine Corps says in a statement. “They were conducting routine flight operations in accordance with applicable regulations when this catastrophic and unanticipated mechanical failure occurred.”
In the statement the Marine Corps states it has since 2010 made “numerous actions associated with defining, mitigating or eliminating HCEs.”
In February, the V-22 Joint Program Office (PMA-275) announced the whole fleet would undergo input quill assembly (IQA) replacement even though the full root cause of the HCE has not been determined. The AIB report states IQAs are being replaced every 800 hours. Since then, there have been 22,258 flight hours with no reported HCE events.
a hard clutch engagement (HCE)
“The completion of this investigation does not close the HCE effort within PMA-275,” says Col. Brian Taylor, PMA-275 program manager, in a statement. “The implemented IQA life limit, which reduced overall V-22 HCE risk by greater than 99 percent, was not a result of this investigation but is certainly reinforced by its findings.”
The HCE issue is one of 13 Category 1 deficiencies on the V-22 fleet, issues that are defined as possibly affecting safety of flight. The program office has declined to identify the other deficiencies.
After the grounding was first announced, Air Force Special Operations Command was the first command to look back at past V-22 mishaps to see if what is now understood about the HCE phenomena would have changed the findings. The Navy and Marine Corps followed suit. AFSOC said at the close of that investigation that what is known would not “materially” change---while HCEs could not completely be ruled out of some, it did not merit re-opening the investigations.
hard clutch engagement (HCE)
One of the most notable incidents was the April 2010 crash of an Air Force V-22 in Afghanistan that killed four and injured 16. The official account of the crash did not identify a main cause since key pieces of evidence, such as the flight data recorder and an entire engine, were missing. However, then-AIB president Brig. Gen. Donald Harvel wrote there was an “abnormal engine response” and the proprotor’s speed was low when it attempted a rolling landing. AFSOC at the time disagreed with the findings, and issued a statement blaming the pilots.
Harvel, who retired shortly after and died in 2020, wrote his account of the investigation in a book titled Rotors in the Sand. In a chapter called “My Unofficial Opinion of What Really Happened,” Harvel wrote that gearbox problems were likely a cause.
Rotors In The Sand: Harvel, Don: 9781098303327: Amazon.com: Books
Rotors in the Sand
by Donald Harvel
“My Unofficial Opinion of What Really Happened,”
gearbox problems were likely a cause.
Brian Everstine
Brian Everstine is the Pentagon Editor for Aviation Week, based in Washington, D.C. Before joining Aviation Week in August 2021, he covered the Pentagon for Air Force Magazine. Brian began covering defense aviation in 2011 as a reporter for Military Times.
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- ongoing gearbox transmission problems.
- Lt. Gen. Jim Slife, AFSOC commander
- services explores installing new gearbox assemblies
- marine corps, navy and japan are not yet following u.s. air force's lead
- sprag clutch component of the proprotor gearbox,
- although the Marine Corps, for example, says it has been a known issue since at least 2010.
- November 16, 2022
- hard clutch engagement
- The problem centers on the sprag clutch component of the proprotor gearbox, a part that connects the tilting Rolls-Royce AE 1107C engines to the proprotors.
- installing rebuilt input quill assemblies on all CV-22s—a remanufacture of a key component of the proprotor gearbox that is sheared during a hard clutch engagement—with new inner and outer races and sprag clutches.
Donald Harvel
Rotors in the Sand
“My Unofficial Opinion of What Really Happened,” which asserts that gearbox problems were a cause.
- “The crew had no idea of what caused the power loss situation,” Harvel writes. “There were no procedures, and no information in their flight manuals about clutch failure. However, they would get other ‘cautions’ posted on their engine instruments relating to driveshaft and gearbox components attached to the right engine.”
- “The engine was running, but the proprotor gearbox clutch was broken. In fact, I think both engines were running. They were operating at an abnormally low power.”
- compressor stall => dumped fuel to reduce weight
- compressor stall => dumped fuel to reduce weight => increased thrust to full power to try to reverse the rapid descent
- compressor stall => a surge in torque to the right engine, breaking the proprotor gearbox clutch => destroying the engine => crash
- clutch failure
- ‘cautions’ light driveshaft components
- ‘cautions’ light gearbox components
- proprotor gearbox clutch was broken.
- sprag clutch slippage => hard clutch engagement
- the clutch is slipping
- replace components with enough time on them ... slip
- Lt. Gen. Jim Slife, AFSOC commander
- November 16, 2022
- “When we did our stand-down in August, at the time I highlighted that we did not know of any catastrophic mishaps that had been caused by the hard clutch engagement,” Slife tells Aviation Week. “But it is a serious phenomenon, and AFSOC has had a number of these events that were kept from being catastrophic by pretty impressive feats of airmanship by the crews flying the airplanes.”
- “Essentially the question that I asked and impaneled our team to go answer was: Would what we now know about the hard clutch engagement phenomenon—when it happens, how it manifests itself and so forth—would that knowledge materially change any of the findings or conclusions of any prior board, where perhaps we just didn’t understand the phenomenon of these sprag clutch slippage events and the subsequent hard clutch engagement? That was the scope of what we did,” Slife says.
- “We know we have to identify the root cause of why the clutch is slipping in the first place and fix whatever the root cause is,” Slife says. “So I don’t know that the clutch is the root cause. But we do know that the clutch is slipping, and so we’ve got to work back and figure out what the root cause is.”
- can you stressed test the clutch, forcing it to slip?
- stressed test the gearbox?
- “In the meantime, can we replace the components that are subject to slipping? [These are] some of the details inside the clutch and the sprags themselves, the inner and outer races of the clutch,” Slife says. “Can we replace components on a time-change schedule to make sure that we’re avoiding clutches with enough time on them that they might be subject to slipping?”
- “Early in my career, the battle of Mogadishu, [Somalia,] in 1993 was the first time that people I personally knew were killed in combat,” he recalls. “It left a mark on me. I never, as a leader, want to be in a position where I would look back at something that I asked somebody to do and wish that I would have changed something when I had the opportunity to. So this is kind of the Mogadishu test for me.”
- “I’ve had to bury my friends, and I don’t want to do any more of that than I have to,” he says. “That was kind of what led us down this path in the first place. I think we’re in a better place, even if we don’t fully understand what’s going on inside the input quills themselves.”
- November 16, 2022
Gearbox Issue’s Root Cause Elusive As USAF Investigates V-22 Crashes
Brian Everstine November 16, 2022
An Air Force CV-22 was forced to land in Norway, prompting a grounding of the service’s Ospreys to investigate ongoing transmission problems.
ongoing gearbox transmission problems.
For most of the Bell-Boeing V-22 Osprey’s service life, operators have tried to work around a phenomenon inside the tiltrotor’s gearbox: The sprag clutch slips, causing a subsequent hard engagement that can damage the engine and affect flight safety.
In mid-August, U.S. Air Force Special Operations Command (AFSOC) grounded its CV-22s after an Osprey was forced to land in a remote area of Norway. The incident prompted AFSOC Commander Lt. Gen. Jim Slife to ask: If the sprag clutch phenomenon forced this Osprey into a hard landing, could it be responsible for other mishaps? And as the problem becomes better understood, are there interim steps that can be taken to improve safety, even if the root cause of the slippage remains elusive?
- Lt. Gen. Jim Slife, AFSOC commander
- services explores installing new gearbox assemblies
- marine corps, navy and japan are not yet following u.s. air force's lead
“When we did our stand-down in August, at the time I highlighted that we did not know of any catastrophic mishaps that had been caused by the hard clutch engagement,” Slife tells Aviation Week. “But it is a serious phenomenon, and AFSOC has had a number of these events that were kept from being catastrophic by pretty impressive feats of airmanship by the crews flying the airplanes.”
- ongoing gearbox transmission problems.
- sprag clutch component of the proprotor gearbox,
- hard clutch engagement
The problem centers on the sprag clutch component of the proprotor gearbox, a part that connects the tilting Rolls-Royce AE 1107C engines to the proprotors. AFSOC recently conducted a review of 62 severe mishaps over the entirety of the CV-22’s service life, looking at both classified investigations and publicly released reports. A group of subject matter experts and legal advisors combed through the available data to discern whether what is known about the hard clutch engagement could have been a contributing factor to the incidents. The V-22 Program Office, along with the Navy and Marine Corps, followed suit, looking at their own history of mishaps to see if the issue could answer questions about the crashes.
The results, Slife and the other services say, is that none of the findings would be “materially” changed based on what is now known. That does not mean a hard clutch engagement was not involved in some way in the mishaps. It just means that the existing investigations would not be substantially changed by what could be gleaned from new reviews, so there is no merit in the extremely rare step of reconvening an investigation, Slife says.
AFSOC, the only command to ground its V-22 fleet because of the hard clutch engagement, is also the only one looking to go forward with a potential change to its aircraft to mitigate the issue. The command said in a statement that it is exploring with Bell-Boeing potentially installing rebuilt input quill assemblies on all CV-22s—a remanufacture of a key component of the proprotor gearbox that is sheared during a hard clutch engagement—with new inner and outer races and sprag clutches. Slife says the command is finalizing its decision, determining overall impacts to the fleet if the replacements go forward. The V-22 Program Office said in a statement that it supports AFSOC’s plan. The Marine Corps and Navy are still determining whether to follow suit.
- ongoing gearbox transmission problems.
- sprag clutch component of the proprotor gearbox,
- hard clutch engagement
- installing rebuilt input quill assemblies on all CV-22s—a remanufacture of a key component of the proprotor gearbox that is sheared during a hard clutch engagement—with new inner and outer races and sprag clutches.
Controversial Crash
One of the worst mishaps in AFSOC’s recent history was a driving factor in the decision to conduct the review—an April 2010 crash in Afghanistan that killed four and injured 16 on board. The crash became well known because of some controversy surrounding the investigation, with the command at the time publicly rebuking the top investigator.
The Air Force’s official account of the crash, the publicly released Accident Investigation Board (AIB) report, did not identify a main cause because key pieces of evidence, including one entire engine and the flight data recorder, were missing or destroyed. The report stated that engine power loss was a potential contributing factor, with ground markings and video from a nearby A-10 showing engine degradation and an “abnormal engine response.” An analysis showed that proprotor speed was low when the aircraft attempted a rolling landing on a rough surface, then-AIB President and Brig. Gen. Donald Harvel wrote.
However, AFSOC at the time disagreed with Harvel’s findings, issuing a statement that engine power loss could not have been a major factor in the crash. It instead blamed the pilots.
Donald Harvel
Rotors in the Sand
“My Unofficial Opinion of What Really Happened,” which asserts that gearbox problems were a cause.
- ongoing gearbox transmission problems.
- sprag clutch component of the proprotor gearbox,
- hard clutch engagement
- installing rebuilt input quill assemblies on all CV-22s—a remanufacture of a key component of the proprotor gearbox that is sheared during a hard clutch engagement—with new inner and outer races and sprag clutches.
Harvel retired shortly after the report was released, but he later wrote a book about the crash, the AIB process and the command’s response. The book, Rotors in the Sand, includes a chapter titled “My Unofficial Opinion of What Really Happened,” which asserts that gearbox problems were a cause. He writes that when the Osprey was descending, the left engine experienced a compressor stall, and the flight engineer dumped fuel to reduce weight. Crewmembers were overwhelmed by a sudden loss of engine power, and the pilot increased thrust to full power to try to reverse the rapid descent. The stall led to a surge in torque to the right engine, breaking the proprotor gearbox clutch and destroying the engine.
“The crew had no idea of what caused the power loss situation,” Harvel writes. “There were no procedures, and no information in their flight manuals about clutch failure. However, they would get other ‘cautions’ posted on their engine instruments relating to driveshaft and gearbox components attached to the right engine.”
A Rolls-Royce analysis of an engine recovered after the Osprey was destroyed found that it was running, not shut down, at the time of the crash. Harvel agreed: “The engine was running, but the proprotor gearbox clutch was broken. In fact, I think both engines were running. They were operating at an abnormally low power.” The incident was referenced in later reports about Osprey crashes, but the investigation was not revisited. Harvel died in 2020.
Slife says this crash and another two years later—at Hurlburt Field, Florida, that resulted in the aircraft being destroyed but no fatalities—remain mysteries to him. He was personally close to both incidents. A longtime friend, Senior Master Sgt. James Lackey, died in the Afghanistan crash, and Slife attended his funeral and gave the eulogy. At Hurlburt, he was the wing commander at the time of the crash.
“Essentially the question that I asked and impaneled our team to go answer was: Would what we now know about the hard clutch engagement phenomenon—when it happens, how it manifests itself and so forth—would that knowledge materially change any of the findings or conclusions of any prior board, where perhaps we just didn’t understand the phenomenon of these sprag clutch slippage events and the subsequent hard clutch engagement? That was the scope of what we did,” Slife says.
- compressor stall => dumped fuel to reduce weight
- compressor stall => dumped fuel to reduce weight => increased thrust to full power to try to reverse the rapid descent
- compressor stall => a surge in torque to the right engine, breaking the proprotor gearbox clutch => destroying the engine => crash
- clutch failure
- ‘cautions’ light driveshaft components
- ‘cautions’ light gearbox components
- proprotor gearbox clutch was broken.
- sprag clutch slippage => hard clutch engagement
“And the answer that came back [was] that there are no findings or conclusions from any of the prior investigations that would have been changed by what we now know about hard clutch engagements,” he continues. “That doesn’t mean that hard clutch engagements were not present in any of those previous mishaps that we looked at; it just means that the findings and the conclusions of the investigations themselves would not have been materially changed by our current understanding of that phenomenon.”
For the Afghanistan crash, the ability to reinvestigate the incident was limited. There was very little evidence. The aircraft was destroyed and the crash site ransacked after the responding ground force did not retrieve the data recorder. The AFSOC team looked at testimony given at the time, though the co-pilot said during the original investigation that he could not recall the crash. Slife says Harvel’s formal report at the time concluded that an unexplained mechanical malfunction was the cause. What is now known about the hard clutch engagement “neither supports nor undermines that conclusion,” Slife says.
“Could that have been part of the sequence of events that led to that crash?” he asks. “It could have, we just don’t have any evidence that would suggest that’s the case. And so . . . it didn’t warrant a reopening of the investigation because it didn’t tell us anything about that specific mishap that we didn’t already know.”
Looking for the Root Cause
None of the V-22 operators know the root cause of the hard clutch engagement issue, although the Marine Corps, for example, says it has been a known issue since at least 2010. When the Air Force grounded its fleet in August, the Marines and Navy kept flying and said their aircrews know how to work around it. It is one of 13 Category 1 deficiencies that could affect flight safety of the V-22 fleet. The program office declined to identify the other deficiencies.
Slife says AFSOC crews have changed how they fly, including procedural changes to adjust how power is applied for tactical takeoff-and-departure operations as part of risk controls in place.
A data collection effort is underway to continue investigating the issue. When an Osprey experiences a hard clutch engagement, the clutch is sent to Bell-Boeing to examine the material and help determine a long-term fix.
“We know we have to identify the root cause of why the clutch is slipping in the first place and fix whatever the root cause is,” Slife says. “So I don’t know that the clutch is the root cause. But we do know that the clutch is slipping, and so we’ve got to work back and figure out what the root cause is.”
- the clutch is slipping
- replace components with enough time on them that they might slip
In the short term, AFSOC is looking at replacing the input quill assemblies to get ahead of a potential hard clutch engagement incident. “In the meantime, can we replace the components that are subject to slipping? [These are] some of the details inside the clutch and the sprags themselves, the inner and outer races of the clutch,” Slife says. “Can we replace components on a time-change schedule to make sure that we’re avoiding clutches with enough time on them that they might be subject to slipping?”
AFSOC is working with Bell-Boeing on the effort. It would not be a quick fix, as AFSOC and the program office are trying to understand industry’s timeline for building the new components and plan for installations across the Osprey fleet. The command estimates installations would take about six months to incorporate across the fleet, once new components are delivered. Bell-Boeing has not outlined any potential manufacturing timeline, referring questions to the program office.
As AFSOC progresses, the Marine Corps, Navy and the Japan Ground Self-Defense Force are determining whether to follow suit, the Marine Corps and the program office said in statements.
Slife says his connections to the 2010 and 2012 incidents, along with experiences early in his career, shaped his decision to ground the CV-22 fleet in August and how he is proceeding with AFSOC’s Osprey plans.
“Early in my career, the battle of Mogadishu, [Somalia,] in 1993 was the first time that people I personally knew were killed in combat,” he recalls. “It left a mark on me. I never, as a leader, want to be in a position where I would look back at something that I asked somebody to do and wish that I would have changed something when I had the opportunity to. So this is kind of the Mogadishu test for me.”
If the fleet kept flying after the incident in Norway, and then another incident happened during which airmen were killed and a subsequent investigation found a hard clutch engagement had contributed to it, Slife says, he would look back at his decisions and wonder if he had done everything he could have to get to the root cause of the problem.
“I’ve had to bury my friends, and I don’t want to do any more of that than I have to,” he says. “That was kind of what led us down this path in the first place. I think we’re in a better place, even if we don’t fully understand what’s going on inside the input quills themselves.”
Brian Everstine
Brian Everstine is the Pentagon Editor for Aviation Week, based in Washington, D.C. Before joining Aviation Week in August 2021, he covered the Pentagon for Air Force Magazine. Brian began covering defense aviation in 2011 as a reporter for Military Times.
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https://www.nytimes.com/2001/04/06/us/marine-corps-report-links-fatal-osprey-crash-to-software-malfunction.html
Marine Corps Report Links Fatal Osprey Crash to Software Malfunction
By James Dao
April 6, 2001
Problems began in the night training mission when a hydraulic line in one of the Osprey's two engine casings burst as the aircraft was approaching the New River Air Station in North Carolina.
The ruptured line caused warning lights to go off in the cockpit, including one on a computer reset button. The pilot, Lt. Col. Keith Sweaney, pushed that button, a standard procedure that should have resulted in no perceptible change in the aircraft.
But instead of resetting the controls, the software changed the pitch of the Osprey's rotors, causing the aircraft to accelerate unevenly.
Not realizing that the reset button was causing the problem, Colonel Sweaney punched it as many as 10 times trying to regain control. Instead, the aircraft pitched and rolled like ''a bucking bronco,'' as one analyst put it. Thirty seconds after the hydraulic line broke, the Osprey's rotors stalled, and it crashed.
The Ospreys have long had problems with their hydraulics lines, which are made of light titanium, which cracks easily. The Osprey uses an unusually high-pressure hydraulic system, which can generate more power in a more compact unit.
An array of recent reports cited problems with Osprey hydraulic leaks that caused engine failures and fires. Last month, an inspection found that all eight of the corps' Ospreys had hydraulic line problems, the report said.
The report concluded that the aircraft's manufacturers, Boeing and Bell Helicopter Textron, should redesign the hydraulic system and the engine casing to prevent hydraulic lines from being so easily frayed.
But the report also asserted that without the software malfunction, the Osprey probably could have limped to a safe landing. The report said that the software had been tested in December 1996 but that those tests did not adequately check the reset system. If they had, the report concluded, the deficiency ''may have been discovered.''
The software code was written by BAE Systems and was integrated with the Osprey's hardware by Boeing, Pentagon officials said.
https://www.nytimes.com/2001/04/06/us/marine-corps-report-links-fatal-osprey-crash-to-software-malfunction.html
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Hydraulic Problems Vex V-22
Apr. 04, 2007
(Source: Project On Government Oversight; issued April 3, 2007)
The MV-22 Osprey continues to experience technical glitches, including recurring hydraulic problems. (US DoD photo)
The Fort Worth Star-Telegram reported this weekend that a Marine V-22 Osprey experienced a hydraulic leak that led to an engine fire last Thursday:
“The Marine MV-22, assigned to the squadron that is expected to be the first to be deployed overseas this year, was preparing to take off from the Marine base at New River, N.C., when the crew got warnings of a fire and hydraulic leak in the right-hand engine nacelle.
An official statement released by the Marines public affairs office at New River called the incident "a minor nacelle fire."
But a former Marine V-22 maintenance supervisor, Josh Brannon, said "it's silly to suggest any fire is minor." Had the fire occurred a few minutes later during flight "they could have been having a funeral," said Brannon, who now supervises maintenance of medical-evacuation helicopters in South Carolina.
According to an early report of the incident sent out by the Naval Aviation Maintenance Discrepancy Reporting Program, this is not as minor as a problem as the Marine Corps public affairs office at New River indicates. The report states:
THIS IS A PROBLEM WE HAVE SEEN IN OTHER SQUADRONS. IT IS APPARENT THAT THIS IS A SIGNIFICANT PROBLEM IN THE MV-22 COMMUNITY. THIS IS THE 10TH REPORTED INSIDENT [sic] OF AN EAPS QD [Engine Air Particle Seperator Quick Disconnect] BACKING OFF. [emphasis is POGO's]
In February, the Naval Air Systems Command issued a notice that it is going to award Bell-Boeing, the V-22's contractor, a sole source contract "for the non-recurring development and recurring implementation of design solution in both production and retrofit for the V-22 Engine Air Particle Separator (EAPS)." This contract is intended to fix the problem.
The V-22's hydraulic problems are not new. According to the Defense Department Inspector General in 2002:
“The V-22 was produced with a less-than-optimal hydraulic system because the V-22 Program Manager (PMA-275) did not exercise sufficient oversight of the hydraulic system's design: PMA-275 did not specifically monitor the reliability rates of the hydraulic system's performance.”
- reliability rates of the hydraulic system's performance.
The Star-Telegram's Bob Cox also reported:
A more serious nacelle fire occurred on a Marine MV-22 at New River in December. The Marines said that fire, which erupted moments after the plane landed, caused at least $1 million in damage to the aircraft.
That fire was caused when the titanium fitting on the hydraulic line failed and spurted fluid.
The aircraft has suffered other engine nacelle fires caused by leaking hydraulic fluid, including some that the Marines have not publicly acknowledged, according to internal Marine correspondence provided to the Star-Telegram.
POGO will continue monitoring the V-22 program. The GAO noted in a report last week that the "Design stability of Block B--the deployed configuration [of the V-22]--will be better known after its limited operational assessment in late 2007...A bearing defect has been found in some critical assemblies of production aircraft and is being addressed."
- A bearing defect has been found in some critical assemblies of production aircraft and is being addressed.
-ends-
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https://en.wikipedia.org/wiki/Accidents_and_incidents_involving_the_V-22_Osprey#bodyContent
https://en.wikipedia.org/wiki/Accidents_and_incidents_involving_the_V-22_Osprey
https://en.wikipedia.org/wiki/
July 1992
On 20 July 1992, pre-production V-22 #4's right engine failed and caused the aircraft to drop into the Potomac River by Marine Corps Base Quantico with an audience of Department of Defense and industry officials.[8][9][10] Flammable liquids collected in the right nacelle and led to an engine fire and subsequent failure. All seven on board were killed and the V-22 fleet was grounded for 11 months following the accident.[1][11][12] A titanium firewall now protects the composite propshaft.[13]
April 2000
https://en.wikipedia.org/wiki/2000_Marana_V-22_crash
It descended faster than normal (over 2,000 ft/min or 10 m/s) from an
unusually high altitude with a forward speed of under 45 miles per hour (39 kn; 72 km/h) when it suddenly stalled its right rotor at 245 feet (75 m), rolled over, crashed, and exploded, killing all 19 on board.[14][15]
vortex ring state (VRS),
December 2000
On 11 December 2000, a V-22 had a flight control error and crashed near Jacksonville, North Carolina, killing all four aboard.
A vibration-induced chafing from an adjacent wiring bundle caused a leak in the hydraulic line, which fed the primary side of the swashplate actuators to the right side rotor blade controls.
The leak caused a Primary Flight Control System (PFCS) alert.
A previously-undiscovered error in the aircraft's control software caused it to decelerate in response to each of the pilot's eight attempts to reset the software as a result of the PFCS alert.
The uncontrollable aircraft fell 1,600 feet (490 m) and crashed in a forest. The wiring harnesses and hydraulic line routing in the nacelles were subsequently modified. This caused the Marine Corps to ground its fleet of eight V-22s, the second grounding in 2000.[1][17][18]
March 2006
A MV-22B experienced an uncommanded engine acceleration
Since the aircraft regulates power turbine speed with blade pitch, the reaction caused the aircraft to go airborne with the Torque Control Lever (TCL, or throttle) at idle.
It was later found that a miswired cannon plug to one of the engine's two Full Authority Digital Engine Controls (FADEC) was the cause. The FADEC software was also modified to decrease the time needed for switching
between the redundant FADECs to eliminate the possibility of a similar mishap occurring in the future.[21]
The aircraft was found to be damaged beyond repair and stricken from Navy's list in July 2009.[22][23]
April 2010
The investigation found several factors that significantly contributed to the crash: these include low visibility, a poorly-executed approach, loss of situational awareness, and a high descent rate.[28]
Brig. Gen. Donald Harvel, board president of the first investigation into the crash, fingered the "unidentified contrails" during the last 17 seconds of flight as indications of engine troubles.[29] Harvel has become a critic
of the aircraft since his retirement and states that his retirement was placed on hold for two years to silence him from speaking publicly about his concerns about the aircraft's safety.[30] The actual causes of the crash may never be known because US military aircraft destroyed the wreckage and black box recorder.[31]
April 2012
An MV-22B belonging to 2nd Marine Aircraft Wing, VMM-261 was participating in Exercise African Lion when it crashed near Tan-Tan and Agadir, Morocco, on 11 April 2012, killing two Marines. Two others were seriously injured, and the aircraft was lost.[33][34][35]
June 2012
On 13 June 2012, a USAF CV-22B crashed at Eglin Air Force Base in Florida during training. All five aboard were injured;[38] two were released from the hospital shortly after.[39] The aircraft came to rest upside-down and received major damage.[40] The cause of the crash was determined to be pilot error [??], with the CV-22 flying through the proprotor wash of another aircraft.[41]
May 2015
An MV-22B Osprey participating in a training exercise at Bellows Air Force Station, Oahu, Hawaii, sustained a hard landing which killed two Marines and injured 20.[43] The aircraft sustained fuselage damage and a fire onboard.[44][45] The aircraft was determined to have suffered dust intake to the right engine, leading the Marine Corps to recommend improved air filters, and reduced allowed hover time in dust from 60 to 30 seconds.[46][47]
December 2016
August 2017
September 2017
March 2022
An MV-22B Osprey participating in NATO exercise Cold Response crashed in Gråtådalen, a valley in Beiarn, Norway on 18 March 2022, killing all four Marines onboard.[64][65][66] The crew were confirmed dead shortly after Norwegian authorities discovered the crash site.[67] Investigators concluded that the causal factor of the crash was pilot error due to low altitude steep bank angle maneuvers exceeding the aircraft's normal operating envelope.[68] Investigators noted that an unauthorized personal GoPro video camera was found at the crash site and was in use at the time of the crash. "Such devices are prohibited on grounds that they can incentivize risktaking and serve as a distraction; that may have been the case with Ghost 31," the report reads.[69]
June 2022
An MV-22B Osprey belonging to 3rd Marine Aircraft Wing crashed near Glamis, California, on 8 June 2022, killing all five Marines onboard. Among the fatalities was Captain John J. Sax, son of the former Major League Baseball player and LA Dodger Steve Sax.[70] The accident investigation determined that the crash was caused by a dual hard clutch engagement causing catastrophic malfunction of the aircraft's gearbox that lead to drive system failures.[71] From 2010 to the time of the crash, there had been 16 similar clutch issues on Marine Ospreys.[72] Initial reports erroneously claimed that nuclear material were onboard the aircraft at the time of the crash.[73][74][75]
From 2010 to the time of the crash, there had been 16 similar clutch issues on Marine Ospreys.[72]
August 2023
A CV-22B Osprey assigned to the US Air Force's 353rd Special Operations Wing crashed into the East China Sea about one kilometer (0.6 mile) off Yakushima Island, Japan, on 29 November 2023, killing all eight airmen aboard. The Osprey, based at Yokota Air Base in Western Tokyo, was flying from Marine Corps Air Station Iwakuni in Yamaguchi Prefecture to Kadena Air Base on Okinawa in clear weather and light winds. Witnesses reported seeing the aircraft flying inverted with flames engulfing the aircraft's left nacelle before an explosion occurred and the aircraft subsequently crashed in waters east of the island near Yakushima Airport. An Air Force investigation into the cause of the crash is ongoing.[78][79][80][81] Japan grounded its fleet of 14 Ospreys after the crash. The US Air Force grounded all of its CV-22 Ospreys one week later.[82] The US Navy and Marines grounded their fleets of V-22 Ospreys pending the outcome of the CV-22 investigation.[83]
Other accidents and notable incidents
July 2006
A V-22 experienced compressor stalls in its right engine in the middle of its first transatlantic flight
A week later it was announced that other V-22s had been having
compressor surges and stalls, and the Navy launched an investigation into it.[86]
December 2006
It was reported that a serious nacelle fire occurred on a Marine MV-22 at New River in December 2006.[87][88]
March 2007
A V-22 experienced a hydraulic leak that led to an engine-compartment fire before takeoff on 29 March 2007.[87]
November 2007
An MV-22 Osprey of VMMT-204 caught on fire during a training mission and was forced to make an emergency landing at Camp Lejeune on 6 November 2007. The fire, which started in one of the engine nacelles, caused significant aircraft damage, but no injuries.[89]
After an investigation, it was determined that a design flaw with the engine air particle separator (EAPS) caused it to jam in flight, causing a shock wave in the hydraulics system and subsequent leaks. Hydraulic
fluid leaked into the IR suppressors and was the cause of the nacelle fires. As a result, all Block A V-22 aircraft were placed under flight restrictions until modification kits could be installed.
2009
An Air Force CV-22 suffered a Class A mishap with more than $1 million in damage during FY 2009. No details were released.[91]
July 2011
On 7 July 2011, an MV-22 crew chief from VMM-264 squadron fell nearly 200 feet (61 m) to his death in southwestern Afghanistan.[92]
October 2014
In early October 2014, an MV-22 Osprey lost power shortly after takeoff from the USS Makin Island. The aircraft splashed down in the Arabian Sea and was briefly partially submerged four feet (one metre) before the pilots regained control and landed on the carrier deck. One marine drowned after his life preserver failed to inflate when he bailed out of the aircraft. The accident was attributed to the aircraft being accidentally started in maintenance mode, which reduces engine power by a fifth.[93]
January 2017
On 29 January 2017, an MV-22 experienced a hard landing during the Yakla raid in Al Bayda, Yemen against Al-Qaeda in the Arabian Peninsula militants, causing two injuries to U.S. troops. The aircraft could not fly afterward and was destroyed by U.S. airstrikes.[94][95][3]
^ "V22 Osprey's 3.2 second accident Flight". i
http://www.iasa.com.au/folders/Safety_Issues/others/Osprey-Leap.html
^ "Osprey Down: Marines Shift Story on Controversial Warplane's Safety Record".
https://www.wired.com/dangerroom/2011/10/osprey-down/
https://www.wired.com/dangerroom/2010/04/controversial-spec-ops-tiltrotor-crashes-in-afghanistan/#more-23620
http://www.dodbuzz.com/2010/05/18/cv-22-lost-due-to-pilot-error/
http://www.afsoc.af.mil/accidentinvestigationboard/index.asp
http://www.airforcetimes.com/news/2011/01/air-force-generals-clash-on-osprey-crash-012211w/
^ Axe, David. "General: 'My Career Was Done' When I Criticized Flawed Warplane"
https://www.wired.com/dangerroom/2012/10/air-force-silenced-general/all/
https://web.archive.org/web/20130726175057/http://www.wired.com/dangerroom/2012/10/air-force-silenced-general/all/
https://www.wired.com/dangerroom/2012/10/osprey-fresh-look/
http://aviation-safety.net/wikibase/wiki.php?id=144945
^ "MV-22 Osprey that crashed in Morocco was mechanically perfect" Yomiuri Shimbun, 9 June 2012. Retrieved: 15 June 2012.
http://www.yomiuri.co.jp/dy/national/T120608005175.htm
^ "AFSOC Crash Report Faults Understanding Of Osprey Rotor Wake".
^ McGarry, Brendan. "Billows of Dust, a Sudden 'Pop' and an Osprey Falls from the Sky". Retrieved 7 August 2017.
http://www.military.com/daily-news/2016/01/29/billows-of-dust-a-sudden-pop-and-an-osprey-falls-from-the-sky.html
^ Katz, Justin (21 July 2023). "'Unpreventable': Deadly 2022 Osprey caused by malfunction, not crew". Breaking Defense. Retrieved 30 August 2023.
https://breakingdefense.sites.breakingmedia.com/2023/07/unpreventable-deadly-2022-osprey-caused-by-malfunction-not-crew/
72. ^ Baldor, Lolita (21 July 2023). "Deadly crash of Marine Osprey last year was caused by mechanical failure, report says". AP News. Retrieved 30 November 2023.
https://apnews.com/article/marine-v22-aircraft-crash-investigation-6a449feb2f590f6d35909a2b40e6839a
^ "Deadly Osprey crash spurred safety changes". The San Diego Union-Tribune. 30 June 2015
http://www.sandiegouniontribune.com/news/2015/jun/30/osprey-crash-at-sea-command-investigation/
Whittle, Richard. The Dream Machine: The Untold History of the Notorious V-22 Osprey. New York: Simon & Schuster, 2010. ISBN 1-4165-6295-8.
https://en.wikipedia.org/wiki/Bell_Boeing_V-22_Osprey
https://en.wikipedia.org/wiki/Accidents_and_incidents_involving_the_V-22_Osprey
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If you're interested in some truth and have the appropriate classified access you should be able to find my vulnerability report via DTIC in the SURVIAC database with search terms of CV-22, vulnerability, OT&E, AFOTEC, 2008.
source:
Top reviews from the United States
JG
5.0 out of 5 stars Truth!
Reviewed in the United States on April 19, 2022
Verified Purchase
I take my hat off to BGen Harvel for his moral stance in the face of unimaginable political pressure. Thank God for senior officers like him! Unfortunately there are very few in my experience. I wish I could've met him before he passed. Reading his book made me frustrated and angry because I have seen from the sidelines over a 20 year AF career a lot of what he experienced first hand. God bless him and his family!
I think most of his conclusions are correct. The only thing I question is his final assumption about the right proprotor clutch failure- certainly possible, but he didn't provide any evidence for that in his book, nor was that malfunction necessary for the ultimate mishap. He's spot on about the crew's instinct to dump fuel- dumping fuel in a low-power emergency was beaten into me from the beginning as an HH-3E copilot and I've done it on more than one occasion during emergencies since then. I'm a 20-year CSAR helicopter pilot and also a defense contractor senior engineer with extensive experience in turboshaft engine degradation due to salt ingestion as well as sand ingestion that can lead to compressor stalls. I have also served as the pilot member on a Class A mishap investigation team so I have some insight into what he went through. I've personally experienced compressor stalls and I think he was spot on in attributing a compressor stall as causal in this mishap. There's no getting around the fact that the pilots screwed up by attempting a landing with a significant tailwind, especially in a CV-22, but the mission pressure was undoubtedly intense and helmet fires were the norm- I'm sure the AC intended a goaround that in the last seconds proved impossible due to compressor stall(s) from degraded engines. I can feel it in my bones from the crew testimonies and from my own experience flying in that kind of horrible environment.
In 2007-2008, as a professional engineer, I was contracted to do a detailed engineering vulnerability analysis of the CV-22 in support of AFOTEC's upcoming IOT&E. My primary task was to research all the previous Bell Boeing vulnerability analyses and determine if they were valid (originally) and if they were suitable to the USAF-intended combat employment environment. My unclassified assessment was that the CV-22 was woefully inadequate for employment into combat. I was in the room the day that the IOT&E was briefed to the AFOTEC commander in late 2008 or early 2009 (can't remember exactly). I was the survivability SME sitting in the cheap seats while watching the AFSOC OT&E pilot desperately try to convince the AFOTEC/CC that the CV-22 was ready for prime time even though his powerpoint slides showed the truth of all the deficiencies in the weapon system. The air was so thick with tension you could cut it with a knife and everyone was sitting at the edge of their seats- it was a hostile briefing. It was obvious that the AFOTEC boss was sick and tired of dealing with this thing over the previous decades and just wanted it out of AFOTEC once and for all. The AFSOC OT&E pilot briefer, in my opinion, is the one most guilty of all for advancing this combat-unsuitable aircraft into operational deployment. There were, and still are, a stunningly massive number of guilty parties supporting the combat employment of this aircraft, but I think he was the worst- He had the opportunity to grow a spine and say the CV-22 was not combat capable yet he didn't; instead he defended it. During the briefing, he at least paused to suggest to the boss that I stand and elaborate on the newly-apparent vulnerability problems, but the boss slammed him for having even spent OT&E money to re-evaluate what Bell-Boeing had done years prior- He didn't want to hear it and I never had the chance to talk. But, the boss also mocked him for recommending fielding the CV-22 when his slides had so much red on them proving it was deficient. Shame on both of them- they both took the political party line and fielded something that although I know is a brilliant piece of technology that may have great civilian application, is entirely unsuitable to the combat mission. I have three sons joining the military and I hope and pray they will never have to fly in it, in either of its forms, the CV-22 or MV-22. If you're interested in some truth and have the appropriate classified access you should be able to find my vulnerability report via DTIC in the SURVIAC database with search terms of CV-22, vulnerability, OT&E, AFOTEC, 2008.
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