LONDON (AP) _ A Royal Air Force pilot who made history by returning to flying after a heart-lung transplant was one of two men killed Thursday in a collision between his jet and a light plane over a Welsh village, police said.

Dyfed-Powys police said the two-seat Jaguar jet and a Cessna 152 plane collided over farmland near Carno, 160 miles northwest of London.

Blazing wreckage fell on the fields, burning many sheep who had to be destroyed.

The jet was on a training mission from Colitshall base in Norfolk, England. One man died and the second was hospitalized after ejecting from the aircraft. The survivor's name was not released.

The dead airman was identified as Wing Cmdr. John Stirling Mardon, 40, the father of two. Last April, he became the first military pilot to return to duty after a heart-lung transplant.

The Cessna crashed near a soccer ground, killing the pilot, the only one aboard.

George White, 21, who was swimming in a stream near the crash, said, ''I heard a tremendous roar and immediately saw the jet slice into the other plane. The little plane seemed to disintegrate.

''The jet came down about half a mile away and I rushed to the scene. I found two RAF men there. One was dead, still in his ejector seat which was more than a foot into the ground.

''It was horrible. ... .

''The other one was lying on the ground, apparently injured. He kept asking, 'What's happened?'''