What technical issues are you talking about?  You left it hanging out there as if it should be assumed that everyone knows what the issues are.  There are the common ones that the know-nothing defense critics throw out, such as the entirely exaggerated vortex-ring state.  As someone who flies the aircraft, citing VRS as a critique of the Osprey pretty much marks that person as someone who knows nothing about the aircraft and who only reads the first sentence in any paragraph.  I'm curious as to what specifically you were getting at.

 

The Osprey is not invulerable, but it will be far more survivable than anything else in theater.  It can fly fast, either at LAT altitudes (<500AGL) or much higher than conventional helos, it has a lower IR and aural signature, and it can out-manuever any helo.  It may have growing pains, but it will do great things on the battlefield.

 

Saying the Osprey's been in development for 18 years, or 25 years, or whatever is like me say I've been cleaning my garage for the past three months.  Some time periods have had a lot more work than others.  The Osprey will be the first in a series of aircraft that will be the next big change in manuever warfare.

They are driven by a transmission, an interconnecting driveshaft between the two nacelles.

 

Having the engines separate and away from the fuselage is a good thing.  It's better to have an IR missile strike away from the cabin.  Also, one engine having a catastrophic failure and shedding turbine blades will not destroy the other.

 

As for the next generation, who knows.  Now that we're finally cracking the code on tiltrotor, it may become the standand.  Sikorsky is working on a high-speed coaxial-rotor helo.  They believe they may have solved retreating blade stall, which has previously prevented high-speed rotorcraft.  It may be a player for the next heavy-lift helo, but right now they're still only on a small-model stage.

The Osprey looks hideously complex to me, especially as it transitions from vertical to horizontal flight. Without compromising anything, do you believe that the next tilt rotor designed that comes out of the Osprey experience will be mechanically simplified? Or will we see variations on the Osprey theme?

I'm specifically asking if the engines might be buried  in the fuselage or in the center wingbox mass, and the rotors/propellers might be driven by a transmission drive instead of putting the engines out there on the ends of the wings.

I know its a dumb question.

Herald

   And they're actually planning a quad-prop heavier lift version of the V-22 (V-44?).  I however have a hard time envisioning it being a naval version that folds up. The folding mechanisms add incredible complexity to the V-22. One has to wonder how much more reliable a non-folding version of the V-22 would be - I'd bet a lot more.  You'd just have to make them quick-disassemble for shipping.

For the future,  perhaps an F-35B (STOVL) engine and fan strapped on either side of an craft might work? Though its still complex, its not nearly as complex as the V-22, and would have massive power.  Just avoid landing sites with grass...

 

Or perhaps just attaching a couple of the F-35B's ducted fans on either side of the craft (perhaps a C-27 with larger engines), still maintaining forward propellers through a clutch mechanism might be the best aircraft. Don't bother to rotate the fans. This solution gets rid of the vertical redirection of hot exhaust gasses as on the F-35B.  I believe I've actually seen talk of using these fans for a VTOL cargo aircraft by Lockheed or the military.

 

Yet another option is that proposed by Groen Brothers Aviation for even heavier lift - A C-27 or even C-130 with its wings clipped outboard of the engines, and a very large rotor blade set on top. The rotor blades would have tip-rockets powered either by jet fuel or hydrogen peroxide and be used only for vertical takeoff or controlled descent vertical landings if auto-gyro landings were not desired.  During forward flight the blades would act in auto-gyro adding lift. Combine some of the Carter-Copter rotor technology, and it could go even faster. I keep thinking they could test this mounting the tip-rocket rotor system from the now defuncted Rotary Rocket on top of a C-27. Imagine a C-130 VTOL. Groen Bros already tried this by modifying a Cessna Skymaster. They removed the rear engine, and mounted a gyro-copter rotor on a mast over the wing root. They feel the C-27 and C-130 are perfect for such a conversion because the wing-root box is already strengthened in the high-wing planes - providing an ideal mast mounting site. Got a spare C-27 you'd like converted? They'd love to talk to you.

 

Pity the X-50 Hummingbird VTOL was abandoned after a couple of accidents in the UAV prototype. One must believe they could have resolved the cross-linkage problems (the problem IIRC). It held great promise for the future of VTOL and it appeared it could easily scaled up. 

 

Its also a pity that research wasn't continued on the Boeing, Sikorsky, Lockheed X-Wing VTOL from the 70's. Today's technologies might have made it a reality. I guess you could however consider the X-50 to be its predecessor.

 

Lots of options for the future - if the military ever gets out of Iraq so it can again invest  in something other than just armored personnel carriers.

 

 

You're correct, I should not have assumed the problems with the V-22 were common knowledge.

 

"In the spring of 2006, a V-22 experienced an uncommanded engine acceleration while ground turning at MCAS New River. 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. After the aircraft was airborne for approx 2 seconds, and 30 feet in the air, the second FADEC recognized the fault, took over, and made the engine speed match the TCL position?idle. The aircraft came back to the ground and one wing broke off, as it is designed to do, to absorb the impact. There were no serious injuries. Pilots now guard the controls during this point in the startup checklist in case of inadvertent flight, so that if the aircraft goes flying, they can keep it flying (push the TCL forward) until the FADEC switch over, then land it safely. The FADEC software was also modified to decrease the amount of time needed for the switch between the redundant FADECs. This correction eliminates the possibility of a similar mishap occurring in the future.^[12]

On 29 March 2007 a V-22 experienced a hydraulic leak that led to an engine-compartment fire before takeoff. Former Marine V-22 maintenance supervisor, Josh Brannon, said that had the fire occurred a few minutes later during flight "they could have been having a funeral." It was also reported at that time that a more serious nacelle fire occurred on a Marine MV-22 at New River in December of 2006. The Marines said that fire, which erupted moments after the plane landed, caused at least $1 million in damage to the aircraft. After the first fatal crash in July of 1992 the engine nacelle was redesigned to provide a drain for spilled fluids, but an engineering investigation after the December of 2006 fire warned that hydraulic fluid leaking in that location of the nacelle would not drain and could easily ignite.^[15]"

They would weaken the structure of the fuselage for what gain? Especially as there is no need to use parachutes for a mass tactical drop from V22s. Land the bleeding things. That's that point of a tilt-rotor.

Why would you want paratroop doors in an aircraft that cannot carry more than two dozen troops?

On 11 July 2006 a V-22 experienced compressor stalls in its right engine in the middle of its first transatlantic flight to the United Kingdom for the Royal International Air Tattoo and Farnborough Air Show.link target=_blank titlelink href="http://www.air-attack.com/news/news_article/1864/V-22-Osprey-Makes-Precautionary-Landing-En-Route-To-UK.html" rel=nofollow>[1] It had to be diverted to Iceland for maintenance. A week later it was announced that other V-22s had been having compressor surges and stalls and the Navy had launched an investigation into it.^[13]

On 10 February 2007 the Air Force and Marine Corps temporarily grounded their entire fleet after discovering a glitch in a computer chip that could cause the aircraft to lose control.^[14]

First, Ppt. Ranger mentions the CH-47 as being a medium-lift platform.  It's a heavy lift platform, and not even germaine to the discussion, as the Osprey is replacing the CH-46E, which is medium lift, and which is the primary helo platform in the Marines, vice the Army, which uses the 47.

 

Second, it's easy to poke at a few PELs and such and make a big deal out of them.  I have over 1000 CH-46 hours, over 1000 TH-57 hours, and over 250 V-22 hours.  I've made a butt-ton of emergency landings in both the CH-46 and TH-57.  How many have I made in the V-22?  Zero.  For an example, FORTY+ years after introduction of the CH-46 and a couple of attempted fixes later, the CH-46 still has utility pump problems.  The thing cavitates, seizes, and actually starts glowing red, then white.  A couple of CH-46Es have burnt to the ground because of this.  How many of these incidents have made national news?  Zero.

 

I'm convinced that I'm safer in the V-22 than in a CH-46, and that's just in terms of flight safety, not in terms of combat survivability, in which it blows the doors off the 46.  I won't speak directly to the malfunctions you listed so thoughfully above, because I don't want to inadvertantly mix in priveleged information, but suffice it to say, most of those were not in the same configuration the fleet birds will be in.  How many F-14s crashed early on?  How many Harriers?  Actually, the more valid comparison is with the transition from props to jets in the late 40's and early '50s.  The mishap rate was huge because we were making a huge leap in capability.  The Osprey and its future bretheren will change the very nature of the battlefield.  It's by no means been perfect, but the Corps will be judged to have done a good job sticking with the V-22 in the final analysis.

"Development of the medium lift Boeing Vertol (models 114 and 414) CH-47 Series Chinook began in late 1956, when the Department of the Army announced plans to replace the H-37 helicopter, which was powered by piston-driven engines, with a new, turbine-powered aircraft."

 

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