The rotors provide lift to keep them up.
They can stay air-born indefinitely - provided there are enough thermal air-currents to keep them aloft.
Helicopter flight schools offer a great training program to get you in the air. Wings Aloft is said to be a great place to learn the basics of flying.
A plane with no engine is a glider. They use the air currents to stay aloft.
A helicopter can stay in the air until it runs out of fule,oil etc. Or until the engine has some sort of failure ex. like it over heats.
Nope. they use a tow plane to get airborne and then ride the air currents to stay aloft.
no NO PLANE CAN STAY IN AIR EXPECT HELICOPTER JUST BECAUSE OF HIS WINGS
The question is not well-formed. Similar questions may include: How many minutes does a helium balloon stay aloft? How long does a hot air balloon stay aloft? How long does a particular rocket motor burn?
The spinning rotor lifts it. The rear rotor stabilises it.
Hot air balloons stay aloft due to the principle of buoyancy. The air inside the balloon is heated, making it less dense than the surrounding cooler air. This causes the balloon to float upward because of the difference in air pressures.
Because the air gets thinner with more altitude, and at some point the thin air can no longer give enough lift for airplanes to stay aloft.
Trial and error. There are many different ways to make a paper aeroplane - some may be better than others.
Air friction slows its forward momentum, and when it goes slower, it doesn't push enough air downwards to stay aloft, and gravity pulls it down.