The Bell Boeing V-22 Osprey: wonder weapon or fatally flawed?

The unorthodox twin-rotor, vertical-takeoff V-22 Osprey has been deployed to Iraq and is expected to fly its first combat missions soon. That means we may learn the answers to questions that have dogged the aircraft -- a joint project of Bell Helicopter Textron and Boeing Helicopters, which is based in Pennsylvania -- throughout its long development.

The U.S. Navy's Osprey home page calls it "The most flexible, capable & revolutionary combat troop transport aircraft in the world."

A recent Time magazine piece, written by a Pulitzer Prize-winning reporter who exposed problems with previous Bell helicopters, calls it "A Flying Shame."

The pilots of the Marine Medium Tiltrotor Squadron 263, or VMM-263, who dub themselves "The Thunder Chickens," will find out which is closer to the truth. As will the up to 24 Marines each Osprey is capable of ferrying into battle.

The Thunder Chickens deployed to Iraq with their 10 aircraft in October, dragging a long train of baggage from the aircraft's lengthy, expensive and troubled development.

At first, the members of VMM-263 were familiarizing themselves with Iraq rather than jumping right into hot spots. Now that is likely to change, the Christian Science Monitor reported on Dec. 7: "Commanders have limited the plane's operations to simpler logistical roles. But now it is set to fly combat missions in Anbar Province, where marines are deployed, that will test the plane's ability to maneuver in more sophisticated and dangerous combat missions."

Last April, The New York Times reported, "The Pentagon has placed so many restrictions on how it can be used in combat that the plane ... could have difficulty fulfilling the Marines' longstanding mission for it."

The Osprey is visible landing near an Iraqi village in this YouTube clip.

The aircraft had a controversial gestation period. Conceived in 1981, the Osprey first flew in 1989 but did not enter service until 2005 — still too soon, according to some critics.

Along the way, it cost $20 billion and killed 30 pilots and passengers. The most disastrous incident occurred April 8, 2000, when a V-22 simulating a rescue crashed in Arizona and exploded, killing all 19 aboard. One of the more disconcerting occurred last year when a running, but unattended Osprey took off on its own and rose about 25 feet before abruptly falling back to the tarmac. The investigation concluded no inherent defect was involved and that in reality two wires had mistakenly been cross-connected during maintenance.

Even Dick Cheney, then Defense secretary and a supporter of most military weapons programs, tried unsuccessfully to kill the Osprey on four occasions, according to Time.

The Osprey's radical configuration — two rotating jet engines attached to stubby little wings and spinning very large rotors — account for some of the cost and a lot of the controversy.

The craft's big advantage is its ability to take off like a helicopter, then rotate its engines for horizontal flight at more than twice the speed of a chopper. It also has a longer range and can fly higher than helicopters.

"The Osprey can deliver Marines to battle more safely, bring them reinforcements over greater distances in greater numbers, and evacuate wounded more quickly," Secretary of the Navy Donald C. Winter said last year. "That all equates to lives saved, as we continue to prosecute the global war on terrorism."

The Marines criticized Mark Thompson's Time story as being "a one-sided, sensationalistic view of the program, full of inaccuracies, and misleading to Time's readers."

Skeptics focus on what they consider the Osprey's serious unresolved problems:

— No autorotation capability. When the engine on a conventional helicopter quits, its rotor will keep spinning, providing enough lift for a hard, but survivable landing. The Osprey's rotors, which are more like propellers, lack that capability. However, either of the Osprey's two engines is capable of driving both rotors, so the loss of one engine would not necessarily be disastrous. If both engines did fail, the military says the craft's stubby wings, which have a thick cross section, provide enough lift to offer hope of it being able to glide to a survivable crash landing.

— Susceptibility to a potentially lethal flight condition known as "vortex ring state," in which, during certain maneuvers, one or both rotors in effect lose their grip on the air. The official investigation of the crash in Arizona that killed 19 found "human factor errors," including a rate of descent far faster than recommended, caused the Osprey to experience VRS, from which the pilot was unable to recover. A technical study after the crash, conducted by Bell and Boeing, concluded that changing the angle of the tilt rotors is a reliable means of recovering from VRS.

— Inadequate defensive firepower. Boeing initially said the Osprey would be fitted with three-barrel forward-firing GAU-19 Gatling gun to suppress enemy forces in landing zones. This weapon fires .50 caliber ammunition at either 1,000 or 2,000 rounds per minute and is capable of destroying light armored vehicles. Instead, the current model's only weapon is a 7.62 mm (.30 caliber) machine gun fired by a gunner out the rear landing bay, which offers a restricted field of fire. The 7.62 mm gun cycles at about 950 rounds per minute and is not powerful enough to penetrate most armor.

In a followup to his "Flying shame" piece, Mark Thompson reported that BAE Systems is working on a gun system that could be attached to the Osprey's belly to provide 360-degree coverage of a landing area. It should be ready in a year or so.

— The aircraft's high cost, more than $100 million each, and high maintenance requirements.

It certainly must have caught the squadron's attention when one of the aircraft suffered an engine fire last month.

No weapon system is perfect, and the Thunder Chickens' experience in Iraq should tell us before long what the strengths and weaknesses of the Osprey really are.

The information in this article, originally published December 11, 2007, was corrected on December 12, 2007. The story initially said that "vortex ring state" (VRS) contributed to two crashes of Osprey aircraft that killed 23 people. In fact, one of the crashes, which killed four, was caused by a combination of a hydraulic line break and problems with flight-control software.