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ARMED FORCES: The F-111 Mystery

5 minute read

The F-111 is a plane you either love or hate. Admirers of the Air Force’s sleek, supersonic fighter-bomber claim that it is the ultimate weapon of modern, tactical aerial warfare. Its critics argue that considering the extraordinary cost of the F-111 ($15.1 million each) and the supposed sophistication of its defensive and safety devices, it has a strange propensity for disappearing during combat missions. The critics would seem to have a case. In 1968, the aardvark-nosed fighter-bombers were taken off combat missions and later shipped home from Viet Nam after three were lost in four weeks of combat flying. The F-111s are now back in action, but they have not proved to be the invulnerable war machines their designers promised. In the past eight weeks, four have disappeared without a trace in the wilds of Southeast Asia. Cost in lives: eight crewmen dead or missing. Cost in hardware: approximately $60 million.

In light of those losses, Wisconsin Senator William Proxmire, a member of the Joint Committee on Defense Production, asked last week that the planes be grounded once again pending further evaluations. “The F-111has often proved to be a death trap to its crews,” he said. “The mysterious disappearance of yet another F-111 makes it appear that the Air Force is unnecessarily risking the lives of American pilots in unsafe and defective planes.”

Proxmire’s harsh judgment may be premature, but there are clearly some highly disturbing and unanswered questions about the Air Force’s controversy-ridden plane. Although the F-111’s overall safety record compares quite favorably with those of other tactical aircraft (only 28 accidents in its first 200,000 flight hours, compared with 73 for Phantom jets), its combat record is discouraging. In five years of noncombat flights in the U.S. and Europe, 20 F-111s have been totally destroyed, but in only twelve weeks of combat missions over Indochina in 1968 and 1972, seven have been lost. Of the four reported missing in the past two months, the North Vietnamese claim to have shot down two and insist that they have the ID cards of two dead crew members. The Air Force has refused to comment on Hanoi’s claims.

Eager. Either way, the losses are equally disturbing. If the planes were lost because of malfunctions, what precisely went wrong? And if they were shot down, what happened to the planes’ sophisticated protective gadgetry? In theory, the F-111 flies so fast and so low that radar cannot lock onto it and antiaircraft crews can hardly see it, let alone track and hit it.

In spite of the recent losses, the Air Force says that it has no intention of grounding the F-111s. Before the fourth plane went down Air Force Secretary Robert Seamons insisted: “We have flown over 1,000 missions out there and three losses in a thousand in combat, while flying tougher missions than any other aircraft over there, is notable. We have no plans to stand down the aircraft.” U.S.A.F. Chief of Staff General John D. Ryan recently returned from Ta Khli Air Force Base in Thailand and told TIME, “The crews are still eager, and they’re still flying missions. I’ve had my own check ride in the F-111 and it’s a hell of an airplane.”

Pilots seem to agree. TIME Correspondent Barry Hillenbrand interviewed several F-111 pilots last week and garnered a bouquet of testimonials. “It’s like sex,” said one pilot. “You don’t know how great it is until you’ve actually tried it.” Another pilot insisted, “Coming out of a fog bank in one of those valleys at that speed is something you would not believe.” Comments a veteran with 17 years’ experience: “I can’t think of any time I’ve heard pilots complain about this plane. It’s a magnificent machine.”

The pilots also provided Hillenbrand with some plausible explanations for the mystery that surrounds every F-111 loss. The plane flies not only under enemy radar but too low to be tracked by American radar or by line-of-sight radio communications. That explains why no emergency messages have ever been received from an F-111 pilot before a combat crash. The planes also fly singly and at night, rather than in groups during daylight. Thus when they go down, there are no friendly witnesses. In fact, no one knows when an F-111 is missing until it fails to make radio contact or is overdue at its home base. By then it is almost impossible to determine where or when the plane was lost in order to recover either the crew or parts of the plane. Says one pilot: “The situation we find ourselves in when we lose a plane is exactly the situation we designed for ourselves.”

That still does not explain why the planes crash in the first place. Although the F-111 was designed as an all-weather craft, some flyers speculate that dense rain squalls in Viet Nam somehow foil the plane’s complex TFR (terrain-following radar), which permits it to skim treetops at 200 ft. above ground at speeds of more than 500 m.p.h. Others suggest that the dense tropical humidity in Southeast Asia somehow damages its complex electronic circuits governing flight and navigational controls. But no one really knows for sure. After returning from an F-111 mission over Laos, one Air Force colonel told Hillenbrand, “I wish we could find the aircraft, too, so that we could find out what’s happening to them. Until we do find them, we simply cannot say what brought them down. We don’t know, and it’s frustrating not to know.”

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