Transport: Future View

Since it really got down to work 21 years ago, the National Advisory Committee for Aeronautics (founded by Act of Congress in 1915) has turned out many a valuable contribution to aircraft and engine design. Its studious scientists, working in a grotesque collection of wind tunnels and other research machinery at Langley Field, Va., can point to NACA discoveries (cowlings, wing designs, etc.) on every airplane flying today.

Last week to Langley Field went some 400 aviation experts, manufacturers and operators to see what NACA has done since the doors of the laboratories were last opened to visitors two years ago. Because this year’s NACA discoveries will be flying in next year’s military airplanes, only U. S. citizens were invited, their cameras were parked at the GHQ Air Force headquarters on the field and they were warned to make no sketches of charts or equipment.

NACA’s research director, Dr. George William Lewis, was proudest of a new wing developed during the past year. Approximately one-half the drag, i.e., the speed-killing characteristic, of the modern airplane is caused by its wings. Most of the wing drag is caused by air friction along the surface which, as the plane speeds through the air, changes from a smooth or laminar flow near the leading edge to a tumbling, churning turbulence farther back on the wing.

NACA’s engineers have succeeded in designing a wing which has laminar flow over virtually its entire surface. The result: reduction of the wing drag by about 67%.

Unfortunately for the visitors, this aeronautical wonder was too wonderful to be shown. Suave Dr. Lewis refused to say how much it would add to the speed of airplanes but it appeared the addition would be 20% to 30% over present design.

Other developments by NACA:

> A new engine cowling which can be used in 500-mile-an-hour airplanes. Cowlings of present design work all right at speeds under 325 m.p.h., but wind-tunnel tests show they cause a “compressibility burble” (violent eddy) above that speed, set up so much resistance that doubling or tripling engine horsepower adds no speed.

> A hydrofoil, or water-wing, used to help a seaplane off the water, retracted later to cut down air resistance.

> A Venetian blind flap, built like a wooden window shade, which gives more lift for slow take-offs and landings than any flap now flying, means that speeds can be made higher without worrying about how fast a high-speed ship will land, how much run it will need to take off.

> An injection device which sprays fuel into engine cylinders to replace carburetors from which vaporized fuel is sucked by the engine. With injection, engine builders can use less volatile fuels, soon to be commercially available, cut down fire hazard.

Dedicated during the day by NACA’s scholarly Dr. Edward P. Warner were two new wind tunnels which are now in operation. In both, NACA engineers work under a pressure of several atmospheres, like sand hogs or divers have to be decompressed before going home at night. In one, studies can be made on fixed models of 19-ft. wingspread in winds of more than 250 m.p.h. In the other a model can be flown as in free air, operated by remote control from a tunnel cockpit. Control is achieved through fine wires to electromagnets in the ship.

Interested spectator at NACA’s spring open house: Colonel Charles A. Lindbergh, member of the Committee and currently on active duty with the Air Corps, who became his old smiling self when assured there were no news photographers around.