The Mohawk averaged nearly 10 serious accidents per 100,000 flying hours between 1972 and 1985, twice the average accident rate for Navy and Marine aircraft, nearly three times the overall Air Force and Army averages for roughly similar periods, according to service records.
Last Sunday, the Georgia Guard was practicing methods to interdict drug smugglers when one of the airplane's two turboprop engines exploded. Within seconds, the plane flipped and crashed in the blue waters south of Miami, the Coast Guard said.
The victims of the crash - Warrant Officer Mark T. Beggs, 26, of Stone Mountain, Ga., and Pfc. Joseph W. Price, 23, of Warner Robins, Ga. - brought to 32 the death toll of Mohawk crashes since 1972. Twenty other people have suffered disabling injuries.
One of the 32 was Phillip Parrish of Macon, Ga., who died in 1975 when another Georgia Guard Mohawk lost an engine and flipped over.
"We had 24 successful flights of the space shuttle and the 25th flight
went up and killed seven people, and they shut down the program. Well, this airplane has killed 32 people and nobody is interested," said Parrish's father and namesake.
The dead include experienced airline pilots serving in the National Guard,
Vietnam combat veterans and instructor pilots such as Parrish's son, whom the Army called "one of the most, if not the most, respected aviators in his unit" - then blamed for causing the crash.
Crashes in 1974 and 1982 killed pilots who were testing the Mohawk's flight characteristics with only one engine operating - a condition that has become a tragic refrain in at least 15 crashes and test reports dating back to 1962.
Typically, the crashes happen so fast that the crew members still are trying to eject when the plane hits the ground. If they do get out, the plane sometimes already has flipped, and the rocket-powered ejection seat blasts them into the ground.
"Consideration ought to be given to grounding the system until this latest crash is evaulated with more detail," said Rep. George W. Darden (D., Ga.). The state Guard Mohawk unit is based in his Marietta district.
The Pentagon last week told Darden that the Mohawk's problems were mostly human error, but Darden said he was more alarmed than reassured by the report. ''It raised some very serious concerns about the safety of the aircraft," he said.
The Mohawk, a short-takeoff airplane, was developed in the late 1950s by the Navy but never used by that service. Instead, the Mohawk became the odd duck of Army aviation.
It is the only high-performance plane and the only plane with ejection seats in the Army, which tends to use helicopters. At first, the Mohawks were armed, but now they carry a variety of ungainly radar and camera pods to spot enemy troop movements.
Only 193 of all versions of the Mohawk remain, including 50 in storage, but the Pentagon wants to overhaul the old airframes for service through the close of the century. The Army and the planm's maker, Grumman Corp., maintain that the Mohawk still is useful and safe.
Grumman will not discuss specifics, but the Army, pilots and other defenders of the aircraft say the Mohawk has no consistent pattern of failure.
The Mohawk's high accident rate, they say, is a statistical glitch caused by the aircraft's limited use and because it often is flown close to the ground and from rough airstrips. The Army generally has attributed crashes to pilot error and assorted mechanical failures.
Last year, though, a Navy admiral who reviewed the investigation of a fatal crash at Norfolk, Va., said the aircraft and the Army, not the pilot, were at fault. He said the Mohawk could not complete a short takeoff with one engine out, as pilots had been led to believe.
"My discussion with several highly qualified OV-1B instructors has revealed that given the same circumstances . . . they also would have expected the aircraft to fly away safely," wrote Rear Adm. J. K. Ready, then commander of the prestigious test-pilot school at Patuxent River, Md.
"In reality, that capability does not exist," Ready wrote, later adding, ''As we now know, the record of successful OV-1B flyaways in the (short- takeoff, one-engine) configuration is dismal."
The Navy investigation tends to confirm other investigation reports obtained under the Freedom of Information Act that suggest the Mohawk has only marginal airworthiness in critical situations.
"An engine failure immediately after takeoff could result in the loss of an aircraft on a hot day," warned an April 1972 report. "The airplane will not climb in the takeoff configuration with one engine feathered (inoperative)," said a March 1970 report.
As early as 1962, a report says that performance requirements for an early Mohawk were changed because the plane could not pass the original one-engine takeoff test.
"Since the test airplane was unable to attain a positive rate of climb with one engine in the takeoff configuration, the takeoff distances could not be demonstrated to meet this guarantee requirement," the report said.
The Army let another life-threatening problem with the Mohawk go uncorrected for years.
The Army Aviation Systems Command in St. Louis said in a written response to questions last year that it had known since 1960 that the Mohawk had a tendency to stall with insufficient warning.
By 1978, the command said, the problem was considered a serious ''deficiency" requiring correction, and investigators warned that unexpected stalls had been a factor in one-fourth of Mohawk accidents, several
of them fatal.
But there was "no resolve" to correct the problem until 1984, the Army command conceded, because of technical problems and a lack of concern by the Mohawk's "user community."
Now, though, it said, stall-warning devices for Mohawks "should be given the highest priority" and "there is no question that safety is the first priority of the leadership of the Army."