Home » Air » Hydraulic Rupture Sparked Osprey Fire

Hydraulic Rupture Sparked Osprey Fire

By Colin Clark Tuesday, September 30th, 2008 8:58 am
Posted in Air

My colleague Christian Lowe at DefenseTech has gotten his hands on an investigation report into a fire that nearly destroyed an MV-22 in November during a training flight near New River, N.C. Here’s his story:

[NOTE: Picture is a scan from one provided in the investigation report]

Turns out, the fire sparked after the #3 hydraulic system ruptured due to pressure spikes from the engine air particle separator which filters inlet air before it is ingested by the engine. The hydraulic fluid spilled all over the IR suppression system, igniting the left nacelle into a ball of flame. The pilots and crew landed safely but the nacelle was a melted, twisted hulk. It caused $16 million in damages.

The crazy part is that this is a known problem. Our friend Bob Cox of the Ft. Worth Star Telegram has reported this same rupture before and his sources in the maintenance community indicate to him the problem is much worse than the Corps admits. In fact, the report shows a Airframe Change notice (#88) that calls for the installation of thicker hydraulic tubing in the EAPS system because of known pressure spikes that can cause a “catastrophic failure.” That notice came out in August, three months before the November incident.

The Corps (an Navy) told us not to worry, this was a problem on the Block A aircraft and the retrofits would go on those. ~~Problem is, the November fire happened on a Block B Osprey.~~ [Turns out this was a Block A.]

Christian is giving the Corps a chance to respond, so you won’t see the final version of the story yet. If you know something, feel free to email me directly. My address is colin.clark@military-inc.com. Let us know how serious you think this issue really is.

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	Al West October 2nd, 2008 at 7:12 am Seems like they need to retrofit all flying units wouldn’t you think?
	timr October 2nd, 2008 at 7:16 am 20 years in development and it still has problems, known problems at that. The Osprey is way to complicated. Maybe the military will continue to use it, but I do not see any civilian usage. To complex, to complicated
	klesb October 2nd, 2008 at 7:29 am Too complex, too complicated. Too expensive.
	hlstill October 2nd, 2008 at 7:50 am This aircraft should be grounded. It has been nothing but a killing machine — 19 die in Tucson. Test air craft falling out of the sky. Too expensive and dangeroues. Why do they still throw money at this thing? With all the other areas needing funds for better ground and troop equipment why waste funds other then to keep some political distric happy and sucking up tax payers money.
	sarguy October 2nd, 2008 at 7:55 am CSAR and Spec ops only. Not a lifter or transport!!
	JDS October 2nd, 2008 at 7:58 am Actually, the concept has been around in prototype form since the early 1960’s…and there are Marine Corps Gazette’s from that era with adverts to prove it.
	Caleb October 2nd, 2008 at 7:58 am And people say that Helo’s and 130’s don’t work well enough.….
	BungeeBob October 2nd, 2008 at 8:05 am What do you expect from a program where the program office is aware of and has proof that the contractor has lied and submitted false and misleading cost information? Only hitch is that the Navy (NAVAIR) program office gets rid of anyone who can find out the truth about corrupt contractors. BTW: there was documented proof in the program office files. I wonder if they purged the evidence. Vibration has been a problem for years. Don’t we warn our kids not to shake items too much?
	david sands October 2nd, 2008 at 8:11 am I WORK ON THE V-22 PROGRAM AT NAS PAX RIVER. I HAVE WORKED ON AIRCRAFT FOR OVER 10YRS AND HAVE TO SAY THE V-22 IS ‘ONE OF THE EASIEST’ AIRCRAFT TO WORK ON. IN MY TIME WITH THE V-22 FROM LRIP — BLOCK B WE HAVE NEVER HAD THIS ISSUE. I HAVE NEVER SEEN AN AIRCRAFT GO FROM THE DRAWING BOARD TO DEP WITH NO PROBLEMS. THIS AIRCRAFT HAS INCREDIBLE POTENTIAL. ASK VMM 263 WHAT THEY THINK OF IT. THERE IS A SMALLER COMMERCIAL BA609 ‘is a civil twin-engined tiltrotor VTOL aircraft’.
	Retrop October 2nd, 2008 at 8:17 am While a man can build anything that the mind can conceive, that does not necesarilly mean that everything conceived should be built. The Osprey fixed wing/rotary wing aircraft is one of the most vivid examples of this. There are way too many laws of physics which are trying to be bent here.
	Carlos V. October 2nd, 2008 at 8:41 am Scrap it! Use the DoD monies for better ground equipment and just supply our forces with what they ask for! Enough is enough! Nothing but a waste of tax dollars and pork barrel money lining someones pockets.
	Steve October 2nd, 2008 at 8:42 am It’s a problem that can be fixed. The V-22 completed 2,500 successful combat mission in Iraq (raids, air assaults, medevac)and flies further, higher and faster than conventional helos…which are more vulnerable to ground fire because of that. It is and will save lives of troops in combat.
	Don Zweifel October 2nd, 2008 at 9:51 am Most rotary wing AC’s have variable pitch rotors which as a consequence allows a change in the angle of attack or pitch. And most fixed wing prop-driven AC’s have variable pitch propellors which provide an opportunity to increase ‘bite,’ i.e., on take-off one increases the angle of attack… once airborne one decreases the A of A for better fuel economy equalling better aerodynamic efficiency. The Osprey should be retrofitted with this feature to enable it to make a much faster transition from VTOL thereby reducing its vulnerability to interdiction. Controllability is subsequently improved with an increased angle of attack. The Osprey would be a much improved platform with this retrofit.
	phrgflyer October 2nd, 2008 at 10:02 am I just see a bunch of naysayers posting about the MV-22. The XV-15 first flew in the 1970’s after everyone said that the aircraft was unsafe. It seems that, yes, there are some problems with the MV-22, but, like with the CH-46A model that broke apart in flight and while landing and caused even more casualties that this aircraft has, was given a chance to prove what it was capable of doing.
	R. Richardson October 2nd, 2008 at 10:10 am Aside from the fact that this is an unsafe aircraft, is the military still using hydralic fluid such as 5606 that will burn? The airlines have been using a fire resistant fluid for as long as I can remember, and I worked on these airliners since 1965.
	Dave Hassett October 2nd, 2008 at 10:34 am I believe, the Osprey’s hydralic system operational psi spec is the highest that has ever been installed in a military aircraft. There were some concerns voiced about this earlier in the aircraft’s development and perphaps it is a real concern. If I remember they needed to push the system to such a high psi in order to allow the cycling of the powerplants to/from vertical
	JCitizen October 2nd, 2008 at 11:41 am If I were a marine, I’d rather use the fantastic performance of this aircraft, despite its misgivings, anyday than trade my life to the certainty of becoming a victim of groundfire. I pity the enemy that will face this system in combat! The capability to swoop in fast and deploy like lightning is just too overwhelming to ignore.
	D0D Conny October 2nd, 2008 at 12:31 pm The PSI Spec has to be high to overcome centrifugal force created by the 38ft rotors as it transitions from vertical to horizontal flight mode.The stress factors on this aircraft is greater than any produced on other aircraft.Failures will occur until this factor can be reduced.
	Maj Eric Dent October 2nd, 2008 at 12:35 pm Like many uninformed bloggers, this fellow is confused about the difference between Block A and Block B Ospreys. The “B” in “MV-22B” does NOT denote Block B. All MV-22 Ospreys currently in operation are designated MV-22B, regardless of whether they are Block A or Block B. This incident occurred in a Block A aircraft flown by our training squadron (which ONLY operates Block A’s). It is unfortunate to sustain damages to any of our aircraft, but we were ahead of the curve on this particular engineering problem and already in the process of making the necessary mods when this incident occurred. Soon after, ALL Block A and Block B MV-22B Ospreys received the modifications described below. a) Larger, thicker-walled titanium hydraulic lines leading to the EAPS have been installed that are capable of sustaining the hydraulic pressure spikes that an EAPS malfunction could cause. b) Hydraulic lines have been re-routed to eliminate bends that potentially place the lines under increased stress and could reduce their ability to withstand excessive spikes in pressure. c) In-line shutoff valves that detect leaks in the system and immediately shut off the flow of hydraulic fluid, minimizing fluid loss have been incorporated. d) The capacity of the annulus, the area in the lower nacelle designed to catch and contain any fluid leaks, has been increased. e) New drain lines out of the nacelle have been installed to more rapidly drain any leaked fluids and carry them out of the nacelle, past the IR suppressor and away from any potential ignition source. ALL Ospreys now have the modifications and they have also been fully incorporated into the V-22 production line so that new aircraft do not require further modification after leaving the factory. This is a success story typically painted with a black brush by the armchair critics. Just by coincidence, this is also the one year anniversary of our incredibly successful Osprey combat deployments to Iraq. The proof is in the performance.
	Zarni October 2nd, 2008 at 12:41 pm Scrap it? Typical attitude these days. If we scrapped every A/C that had problems when it was the first of a kind we would have no planes at all. Everyone wants everything to work right the first time and everytime. The crash that caused alot of deaths was due to pilot error. He was a C-130 pilot not a helo pilot and got into trouble in the helo mode and did what his fixed wing training said to do. He should have done what his helo training said to do.
	Colin Clark October 2nd, 2008 at 2:22 pm This comment from a reader who requested anonymity: “I worked on the Osprey program for over eight years and this is minor compared to the other “known” problems with this aircraft. For instance, the heating elements in the proprotors all short out shortly after every installation on every aircraft, therefore, they cannot de-ice the blades in cold weather. The fix is that they don’t fly when it’s freezing.It takes 42 seconds to transform from airplane mode to helicopter mode, during this time, you are a sitting duck for enemy fire. 33 onboard computers fly this thing, if one goes offline you crash, as this ship cannot be flown manually. I could go on and on, but you get the point. This ship already has killed many, and will kill many more.”
	DensityDuck October 2nd, 2008 at 2:45 pm sigh And we had solved the problem of high-speed-plus-VTOL back in the 1960s, with the AH-56. Take a helicopter and put a prop on it. Indeed, this is still being done today, with the Speedhawk, and Sikorsky’s X2. Hell, I’ll bet ten bucks that an X-45 derivative will fly and be in service before V-22 reaches full deployment…
	David Valento October 2nd, 2008 at 3:21 pm Usually when there’s a 16 million dollar accident that’s happened before, & NO ONE got injured nor hurt, it happened for more then just “accidental’s sake.” “If ‘it’s too good to be true,’ then it prolly is..” <–statement in corilation w/the first/above statement. Basically, I think it was just an insurance scam, and that SOMEONE’S pocket-book(s) got a little fat because of..
	lb3983 October 2nd, 2008 at 7:55 pm I say we just go into the the future with our currently fine jet powered VTOL aircraft not much for transport but give them some time.V-22 sounds like a death trap to me.
	dog October 2nd, 2008 at 10:03 pm i think its a great aircraft once they they get the bugs out of it. i wish we had a craft like that when i was out of the country.
	big mac October 3rd, 2008 at 6:27 am personally i would have to say that it is a good air craft, and people is just going to have to deal with the kinks in the systems untill they can work then out and untill then there will allways be people bitching about it and when it is all said and done and it is in full service people are going to change there attitudes about it
	Jayhawk 9er October 3rd, 2008 at 8:49 am When the military Legal system learns how to write a sound contract, with teeth in it for looking out for the military (USMC, AF, Army, Navy, CG, MM, etc.) thrn this chapter and verse of the continuously ineptitude of that inability. The ones in uniform pay the price and the US Taxpayer takes it in the shorts. When a contract is well written the contractor pays a penalty for not delivering what is requested and to the standards prescribed, not the service or serviceman paying the ultimate price for ineptitude.
	DensityDuck October 3rd, 2008 at 11:24 am I’ve read that the M60A2 was a great tank, we just needed to work the bugs out of it and train people in how to use it properly…
	Paul Aguilar October 4th, 2008 at 12:15 pm Known problem in military aviation, know fix, fix has a kit — all forgotten or ignored. Then, loss of life and/or property is dismissed. This is SNAFU for mil aviation. Now, who do you suppose is picking up the bill for repairs? The Taxpayer.….….hmmm, could be! Who’s going to hang for the oversight.…… no one above the paygrade of O5, GUARANTEED!
	testpilot October 5th, 2008 at 11:00 am It is not an option to not develop the Osprey. The US has to pay the price to keep weapons developers working on the technology for the US. It is far too embarassing and possibly dangerous to face new weapons in the theater. LM, NG, EADS, and Boeing are weapons builders to the highest bidder. They only create patriotic US propaganda when seeking US dollars. They can build it for the US or build it for someone else.
	OspreyTweek October 6th, 2008 at 10:26 am I see many complaints about how this aircraft has so many known issues and therefore should be scrapped. I challenge anyone out there to find any aircraft in any branch of service that does not have any known issues. I also issue the challenge to find me any aircraft that has not caused fatalities or injuries or even as many as the Osprey has caused. This is a very good aircraft, our troops need the specialized support that this aircraft can provide. I think this very incident highlights how well this aircraft is built; even with a catastrophic failure of a hydraulic system and nacelle fire, the aircraft was still able to make it to the ground safely, saving all of the lives on board.
	RotaryWingPilot October 8th, 2008 at 8:39 pm The degree of ignorance on display in parts of the comments section here is second only to the amount of willful stupidity. A couple of pointers for the peanut gallery. The Osprey transitions from VTOL to airplane in just over 10 seconds. The proprotors do adjust pitch, just like any modern helo or fixed wing aircraft. What, do you really think that when it goes faster, the props are just turning at a greater rpm? To the one questioning the “full-deployment” of the Osprey–the Corps is almost done transitioning its 46 squadrons on the East Coast, and an Osprey squadron is beginning the aircraft’s third combat deployment. What else do you want? Mistakes have been made in the past in the Osprey program. They’ve been corrected, and now the Marine Corps has a capability no other armed force possesses. Some other noteworthy aircraft had problems initially–the B-29, F4U, and even the CH-46 come to mind. They were solved, and all of those went on to make huge contributions to our nation’s security.