Plans to deploy a controversial military aircraft now in the final stages of testing were cast into doubt Sunday after 19 Marines were killed in a weekend crash that ranks among the most deadly peacetime accidents in years.
The tilt-rotor MV-22 Osprey, built to take off like a helicopter but then rotate its propellers 90 degrees to fly like a fixed-wing craft, crashed nose down Saturday night near a municipal airport in Marana, Ariz., 25 miles from Tucson.
The Marine Corps aircraft, which was landing when it crashed, was participating in an exercise simulating the evacuation of an embassy from a hostile environment.
Of the 19 dead, 14 were combat troops from Camp Pendleton, north of San Diego; one was from the Miramar Marine Corps Air Station in San Diego; and four were Osprey crew members from a helicopter squadron in Quantico, Va.
"This terrible loss of life is a reminder of how many men and women in the nation's military put their lives at risk, each and every day, so that we might be a free people and the cause of peace can be advanced throughout the world," President Clinton said in a statement issued after he called the commanding officers of the victims.
Military crash investigators probing the charred wreckage of the aircraft Sunday did not speculate in public about the cause of the accident, which occurred about 8 p.m. Saturday.
They will attempt to determine if the crash was the result of mechanical malfunction, pilot error or problems associated with night-vision goggles and the use of forward-looking infrared radar.
No Reports of Major Problems in Testing
Goggles allow crew members to see in the dark but can sometimes impair peripheral vision.
Some witnesses suggested the plane was on fire before the crash.
In response to the crash, a Pentagon spokeswoman said no Ospreys will be flown "until we can get our arms around what may have happened."
The Boeing Co., which is producing the Osprey jointly with Bell Helicopter Textron of Fort Worth, issued a statement calling the crash "a source of great concern and sorrow for all of us" and declining to speculate on the cause.
"Both companies [Boeing and Bell] are cooperating and supporting the Marine Corps to determine the cause of this accident," said the Boeing statement.
Until Saturday's crash, there had been no reports of major problems during the testing phase. The first Ospreys, including the one that crashed Saturday, had flown more than 800 hours without incident. It was the third accident in the history of the aircraft.
A Marine Corps spokesman Sunday declined to say whether the crash might jeopardize plans for the aircraft.
"I don't even want to speculate on that," Capt. Rob Winchester said. "It's going to be based on the investigation."
At the least, the crash was expected to renew concerns about the aircraft engines, which were blamed for a crash in 1992.
The military has experimented with the Osprey for more than a decade at a cost of several hundred million dollars.
Saturday's crash occurred during the final stages of a seven-month evaluation period to determine the aircraft's "operational suitability" for deployment.
The crash came as the Marines were training for a deployment to the Persian Gulf.
The first twin-turbine Ospreys are set to deploy within three years with Marines from a helicopter squadron at New River, N.C. The entire fleet of Ospreys is not scheduled to be ready until 2014.
"Evaluating new equipment and training for war, like war itself, puts life at risk," Navy Secretary Richard Danzig said in a prepared statement. "In peace and war, Marines accept that risk--it is a bond between us."
As investigators began the laborious job of determining the cause of the fiery crash, Marine Corps officers and senior enlisted personnel fanned out across the country to notify the families of the dead and stay with them during the grieving period.
"The entire Marine Corps family grieves for the Marines we've lost in this tragedy, and our thoughts and prayers go out to their families," Marine Corps Commandant Gen. James Jones said.
For Camp Pendleton, the Osprey crash marked the second tragedy in four months. In December, a CH-46 crashed in the ocean during a training mission off Point Loma, killing six Marines and a Navy corpsman.
At $44 million each, the Marine Corps has ordered 360 Ospreys, the Navy 48, and the Air Force 50.
The craft promises greater speed, range and lift capability than current helicopters, thus enhancing the Marine Corps' ability to strike suddenly and with sufficient manpower and equipment to overwhelm and dominate any possible adversary. The Osprey could also be used for rescue missions and drug interdiction.
The Osprey, named for a large, diving bird of prey, is intended to be the Marine Corps' replacement for the aging CH-46 Sea Knight helicopters.