Global Flight 33 is en route from London to New York with Captain Farver in command. The flight crew go about their business as they head for Idlewild on schedule. The head stewardess, Janie, stops in, and Farver suddenly notices a sudden sensation of speed. They wonder if it's a tailwind but they detect nothing. They run a ground speed check and discover they're flying at an impossible 830 knots. They continue to accelerate up to 3000 knots, even though their air speed is steady. They try to contact ground control but are unable to make contact with any tower.
Janie goes back to talk to her co-worker, Paula, and informs her they may be in trouble but to keep a brave face for the passengers. One passenger, a group captain with the British RAF, notices a similar sensation of acceleration. The flight crew are still trying to contact ground control when there's a flash of light and a sudden vibration. Farver wonders if they broke the sound barrier even though there was no warning. They're still unable to contact ground control and Farver orders them down to get a visual sighting, despite the risk of entering other planes' flight paths. Farver reassures the passengers over the intercom and then takes the airplane down through the clouds, while noting the speed sensation has disappeared. They come down over Manhattan Island, only to discover that the buildings have disappeared and there's nothing but jungle. They drop down lower and see... a dinosaur.
Farver sums it up: sopmehow they've traveled through time. With fuel running low, he says they're going to try to catch the mysterious "tailwind" again and hopefully ride it back to their own time. Their ground speed increases again and the same bright light and vibration hit the plane. They go back down through the clouds and spot... New York City. They finally make contact with La Guardia Tower, identifying themselves and requesting radar vector. La Guardia Tower doesn't recognize their call sign or know what a radar vector or a jet aircraft is. Farver tells them that they're running short on fuel, and La Guardia clears them to land. However, as they make their approach they spot an anomaly: the New York World's Fair. They realize that they didn't come back far enough, and they're in 1939. They can't land in 1939, and Farver has no choice but to order them up to try again. Farver gets on the intercom and informs the passengers what is going on, and all they can do is remain calm... and pray.