How can an plane with no engine fly?

Answer 1

AnswerAn airplane that has no power can fly by pointing the nose down and keeping enough speed such that the air flowing over the wings will provide lift. Most aircraft will can only glide such they constantly lose altitude.

Gliders are designed with high-lift wing designs. They will continue to fly as long as there is airflow over the wings that produce lift that equals the weight of their aircraft. Glider pilots will find a wind or a thermal that allows them to maintain altitude while flying into the wind.

Glider pilots look for thermals. This is rising air that is heated by lakes or junk yards or other objects on the ground that produce heat in the sun. The air rises and the glider will find one of these and circle inside this rising air to gain altitude. This is the same thing that Buzzards do when they circle in the air. Many glider pilots will fly in formation with buzzards and eagles, sharing the same free ride.

Once a glider gains altitude and airspeed they have enough energy to fly long distances or even perform loops.

Ridge Soaring - A glider can fly long distances and maintain altitude by flying along the edge of a mountain ridge. They fly by using winds that come up off of the ridge, thus providing a constant wind that provided lift. The glider flys along the ridge in order to stay in the wave of wind coming up. An perfect analogy is a surfer. The surfer catches a wave that is a moving swell in the ocean surface. The surfer propels himself by sliding down the front of the wave. If he gets too far ahead, then he will lose his speed; if he goes to slow, the wave will pass by him. The glide pilot must maintain a similar "balance" or he will begin to descend and loose his lift.