Instead, we saw him calling out ill-considered answers to shouted questions over the noise of helicopter engines.

Off in the distance the roar of a helicopter engine could be heard.

There was a noise-the sound of a helicopter engine high up.

Gipsy Major 200 - Designed as a light helicopter engine.

The helicopter engine failed so the crew stayed for Christmas.

I got out to see what the matter was, and heard the racket of a helicopter engine, right close.

After a long, hot, sweaty time Johnny couldn't hear any more voices or helicopter engines.

He looked up, though, at the sound of an unusual helicopter engine approaching.

If there's anything else to do, I don't know what it is,' the chief machinist's mate shouted over the sound of the helicopter engines.

Finally the sound of helicopter engines once more routed the four men from their chairs.