in long distance flights can an aeroplane fly through space to overcome gravity and hence save fuel?

Answer 1

Absence of air does not mean absence of gravity. Being in orbit has nothing to do with vacuum, the astronauts in orbit are not feeling weightless because they are out of the atmosphere, but because they are going around the earth very fast (7.4 km a second). If they were not orbiting, if they could stay just above, like on a tower 400 km tall (the altitude of the space station), they would still feel 88% of the gravity we feel down here.

Airplane overcome gravity by using the air pressure differential on their wings. Out of the atmosphere, no more lift, the only way to stay aloft then is to go at 7.4 km/s, and that is a tall order. Extra atmospheric crafts are being looked at now, not as a way to save fuel, but as a way to move faster, and that is a very delicate and costly proposition. Subsonic flight is still a lot more economical than the rocket propulsion that would be needed for the final phase of extra-atmospheric flight, if only because a rocket has to bring oxygen along, which airplane find around them in the air.

Answer 2

A conventional aifcraft would have a ceiling of no where near outer or inner space, if it did have enough power to break out of the atmosphere you would surely burn and die on re-entry.

I think a Lockheed Blackbird is the highest flying aircraft in the world, and it leaks fuel and has gaps everywhere at ground level because the metal expands so much at that altitude

Answer 3

Negative. Traveling to space needs a LOT of fuel, even if you overcome gravity.

Answer 4

Air does more than slow a plane down. It holds it up too. To travel through space you'd have to go almost orbital speed to maintain altitude, so it wouldn't save fuel. Suborbital planes have been considered, but to save time. Not money.

Answer 5

Yes, Nasa has done a model of the plane that could escape gravity and travel a much faster than todays.