Without the main engine on, the X-15's instruments and control surfaces remained functional, but the plane could not maintain altitude.

A particular problem with the twin-engine aircraft was that it could not maintain altitude on one engine.

When provided a high launching site the males can maintain altitude and fly some distance.

-has done a good job maintaining altitude, but you're over the Atlantic now.

But the leader came on, until it hung, beating wings now and then to maintain altitude, directly before the entrance of the ship.

As long as the shuttle maintained altitude, it could ride out the storm.

His course change was minor-8 degrees to 92 on the compass, maintaining air speed and altitude.

The weight had been miscalculated and, during the flight, the aircraft could barely maintain altitude.

"Cross the threshold at eight five thousand and maintain altitude."

The aircraft's engine continued to run at the high power level necessary for maintaining high altitude.