GREAT INTEREST IN F111 AIRCRAFT

Press, Volume CVI, Issue 31080, 8 June 1966, Page 17

GREAT INTEREST IN F111 AIRCRAFT

(N.Z. Press Assn.—Copyright) NEW YORK, June 7. In the Western capitals a revolutionary plane with movable wings and a new type of jet engine has become the subject of military and political debate and economic concern, writes Hanson Baldwin, the military editor of the “New York Times.” Baldwin writes: The plane on which the projected defence plans of several nations are centred is the Famous TFX—now designated the Fill—an aircraft born in controversy and developed, as one engineer put it, “in a goldfish bowl." Today, about four years after the plane’s inception, 15 research and development models of the Fill are flying and the first production models of the Air Force fighter-bomber version are scheduled to come off the

assembly lines of General Dynamics Convair plant next January.

So far, the plane has exceeded expectations in some respects—the moveable wing has proved remar ably trouble-free and all pilots who have flown it agree that the aircraft handles beautifully.

But in other respects—weight, excess drag that affects the plane's performance, and costs that have skyrocketed far beyond the original estimates—the Fill has had, and sail has, troubles. Air Force fighter-bomber, reconnaissance and strategic bomber versions, a Navy interceptor for fleet air defence, an Australian strike plane and a special British strike aircraft are nlanned. New Zealand has expressed interest, and the United States Air Force air defence command has considered the Fill for an interceptor role. Though production contracts are still being -egotiated, Convair expects to build 1200 planes of all models, SOO less than content-

plated before the contract was let in 1962. if this quantity is produced, the Fill contract will be one of the fattest t. aviation history, with total costs, including research and development, spares, ground support equipment and other items, approximating between 9000 million and 12,000 million dollars.

Thus the technological hopes, political fortunes, economic well-being and military plans of many governments, services, manufacturing companies and individuals rest upon the Fill. So too do the personal reputations for judgment and technological foresight of many individuals, including particularly that of Secretary of Defence, Robert S. McNamara, the plane’s foremost proponent

The Fill—then designated the TFX or tactical fighter experimental—grew out of requirements for new fighters for the Air Force and the Navy that were outlined in general terms before McNamara took office. Each service had formulated its own

requirements for planes that were to carry out two entirely different missions. The Air Force wanted a high-performance, supersonic aircraft, with fighter superiority and fighter-bomber capabilities, which could be flightferried overseas without refuelling. It was to have supersonic speeds at high altitude and a heavy structural air frame that would withstand the buffeting stresses of speeds above Mach 1 at tree-top height The Navy, on the other band, wanted an aircraft to provide fleet air defence at considerable distance* from the fleet So-called “loiter time”—the capability of the aircraft to remain on air defence station for long periods of time—was one of the Navy’s most important requirements.

Its plane was to have the capability of picking up incoming enemy aircraft by radar—locking on to its targets at great distances—and

was to carry long-range missiles to shoot them down.

In the Navy’s view the mis-

sile was to be the high-per-formance weapon, the plane a long-range radar and launching platform. McNamara and his advisees decided that engineering developments in the variable sweep wing and in jet engines would make it possible to merge both service concepts in one plane. The variable sweep, or variable geometry wing—now called the swing-wing—is simply a wing that can be moved in flight, varying its angle of incidence to the fuse-

lage. The principle is not new and has been tested on other experimental planes, but the TFX is the first operational combat aircraft to utilise a workable swing-wing design. The variable wing, in effect, enables the aircraft to alter its aerodynamic shape In flight It becomes, as the wings change position, several types of aircraft. At take-offs and landings—to reduce landing speed and improve lift—the wings are virtually straight out; at supersonic speeds they are tucked back in a delta-wing pattern.