The Holy Grail of aviation engineering has always been a device that carries a reasonable load, can take off vertically, and flies safely and fast. The V-22 Osprey was supposed to fill those criteria. That it has entered service with the Marines after a tortured and crashed-filled history is perhaps remarkable.
The history of tilt-rotor and VTOL aircraft has been plagued by "dynamic instability." That's the unfortunate tendency of propellers to become very unstable unless the structure to which they are attached is of a certain configuration. Any kind of tilting mechanism changes that configuration as the propeller nacelle moves through the arc.
The tilt rotor resulted from a confluence of interests. The Marines needed a new vehicle to move troops around quickly, their vehicle of choice during WW II the amphibious landing craft having been made obsolete by the atomic bomb. Bell obviously wanted a new helicopter they could sell to the armed services. So when Spivey, Bell's tilt rotor advocate came along, their needs suited perfectly. The Marines existence was in jeopardy for a while, especially as Truman wanted to merge all the forces under one joint command. The Marines being the smallest and the need for boarding from ship to ship having disappeared, they were terrified they were being superseded. (Their lobbying effort was so powerful Truman was quoted as saying they had a propaganda machine as good as Stalin's. It was so good he was forced to apologize for making the statement.)
The catastrophe in the deserts of Iran in the failed attempt to rescue hostages, brought home the frailty of helicopters and the need for an alternative, adding additional fuel for tilt-rotors. (Note that if you have seen the promotional videos for the Osprey you can see how they cleverly suggest it would be immune to the sand problems. The propellers they say are used to clear sand away from the front so visibility is not impaired. I don’t know how much consideration they gave to the unit behind them. Personally, they seem awfully susceptible to the same kinds of issues. See 1:54 of this video for example: http://www.youtube.com/watch?v=NWUThcRihx0 That just can't be good for the machinery.)
Ironically, it had been Iran, under the Shah, that had saved Bell Helicopters with huge contracts, so many that Bell at one time had 8,000 employees living in a town constructed for them by the Iranians. That all came quickly to an end following the Shah's overthrow. (For an excellent book of our the Shah came to power, I can recommend All the Shah's Men: An American Coup and the Roots of Middle East Terror by Stephen Kinzer.)
I suppose if any one person can claim credit for bring the Osprey to fruition it has to be Secretary of the Navy John Lehman who saw the XV-15 at the Paris Air Show and was so taken with it (or perhaps the full court press of Bell Helicopters) that he ordered the Navy, which controls the Marines' budget, to release funds for its development and to squash development of the 130 a new That coupled with Reagan's huge increases in defense spending made the program a virtual certainty.
The book takes us through 2009 but will need to be updated since the future of the thing remains unclear. According to Wired Magazine's article, there have been three accidents involving Air Force V-22s costing four lives. You can watch hagiographic videos on YouTube put out by the Marines. The question I would ask is whether the added speed of "airplane mode", about 316 mph is really needed when existing helicopters it's intended to replace like the Sea Stallion can make about 200 mph. The one advantage would be air refueling and being able to travel longer distances but the payload is much less than conventional aircraft and while in helicopter mode they suffer from the same disadvantages. The way it folds up for transport is really amazing and quite an engineering feat. The V-22 is under consideration to replace the presidential helicopters. If I were president, I don’t think I'd get on one.
Maybe they should number their aircraft differently since the F-22 has a similar problematic accident record. All the services tend to blame people, the pilots, commanders, etc. when the flaw may well be the aircraft itself. In the meantime soldiers die and we hemorrhage money. It's also really ugly.
Note that Bell is now offering the V-280, a third generation tilt-rotor.
"An early version of the V-22, which takes off and lands like a helicopter but cruises like an airplane, crashed four times during testing between 1991 and 2000, killing 30 people. Since entering frontline service in 2009, three of the Air Force’s roughly 20 V-22s have been destroyed or badly damaged in accidents, at the cost of four lives. Likewise, in the last 10 years the Marines’ fleet of some 200 Ospreys has suffered around a dozen major accidents resulting in several destroyed aircraft and no fewer than three deaths."