AVIATION: For Distinguished Flying

On a routine flight from Des Moines to Lincoln, Neb. three weeks ago, United Air Lines flight 329 ran into the kind of trouble that usually means death. Climbing west over Iowa, the twin-engined Convair went out of control and nosed down.

Somehow, while the stewardess reassured the 36 passengers, flight 329's pilot and co-pilot got the nose up. The plane made a belly landing, skidded to a stop in a cornfield. The Convair was wrecked, but no one was seriously injured.

From the crew's description and the wreckage, United learned that a tiny nut in the tail-elevator-trim mechanism had come loose, jamming the controls in dive position. The airline grounded its 54 Convairs as a safety precaution and the Civil Aeronautics Administration sent out orders to all other airlines to check for defective elevator controls on their Convairs.

Last week, the checks completed, United Air Lines' Convair fleet was back in the air, and President W. A. Patterson found a fitting reward for the superb airmanship of flight 329's crew. To Captain E. W. Andreasen, 34, and Co-Pilot T. D. Boyle, 28, he handed bonus checks of $10,000 each; to Stewardess Pat Johnson, 28, he gave $2,500. He also added a postscript: United will pay the income taxes on the bonuses.