# Can a passenger plane stay motionless in air?

I am argueing with my friends that the passenger aeroplanes cannot stay standstill in air, because if the speed reduces below some limit then the plane will start falling.

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The answer is yes although highly unlikely it can and airplane has four forces that it needs to fly. 1)lift-upward force 2) thrust-foward force 3) weight-gravities down force. 4) drag- rearward resistance of airplane surfaces.

If you can make all these forces equal the airplane will fly in place. Now of course for this to be possible on a commercial airliner you would need about a 400-500 mph wind and match it with thrust and you will get your lift.

Source(s): I'm an R/C pilot and I'm a pilot

Yes, if another large bodied object goes parralell to it with the same velocity, then it stops. Then the plane stalls and you all die. Try throwing a ball at 50 miles per hour at a truck going 50 miles towards you. It's pretty cool. Also, what Chris said, a plane NEVER stays motionless in air. The plane is moving respectively to the revolving and orbiting earth. It will always move no matter what even if air resistance makes it look like it.

Sean

Merry XMAS

Theoretically yes! If there is a strong enough wind (say 100knots) and the thrust from the engines balances the drag forces then the plane would stay motionless. Possible in a small plane (microlights have gone backwards) but not very realistic in anything large as you would never find yourself in that situation. For reference to stay airbourne at constant altitude the weight of the aircraft is balanced vertically by = 1/2 x rho x Velocity squared x wing area x co-efficient of lift.

• 5 years ago

As a general rule, no. The plane must always be moving with respect to the air around it, because this is required so that the wings can generate the lift that supports the airplane in the air. In general, this also means that the plane must be moving in relation to the ground. However, if the plane is flying at a speed that is exactly equal to the wind speed over the ground, and it is flying in exactly the opposite direction of the wind, it will remain stationary over the ground as it flies. It is still moving with respect to the air around the plane, but in comparison with the ground it is motionless. This situation is rare because airplanes usually don't fly exactly into the wind and the wind speed is rarely high enough to match the speed of the airplane through the air. For example, a typical small plane might be flying north at 120 knots. In order for it to stay motionless with respect to the ground, it would have to be flying in a wind that is blowing exactly south at 120 knots. Winds of 120 knots are rare at the altitudes that small planes usually fly. The same is true for a large airliner. A larger airliner flies through the air at perhaps 480 knots; in order to remain motionless over the ground, it would have to fly directly into a 480-knot wind, and winds of that speed are unknown even at the high altitudes that airliners fly.

True, a passenger plane cannot stay motionless in the air that is the reason why the plane takes off in such a speed so that it can go against the gravity. The gravity would make the plane crash if it stays motionless in the air.

It is the movement of air over the wings that causes a difference in air pressure above and below the wing which lifts the aeroplane. No movement and the plane would not standstill but move vertically downwards towards the ground.

Their are some military aircraft that can hover, the Harrier jump-jet and Osprey tilt-rotor aircraft, but these don't stay aloft using their wings. They use their engines to maintain hover.

You mustn't forget that air-speed is different to ground-speed. The speed of the plane relative to the air must be maintained so that lift can be achieved but, as has already been said, if the air was moving with the same speed in the opposite direction the plane could maintain zero ground-speed whilst still having the necessary air-speed.

• Anonymous

A plane MUST maintain a relative air speed of 60 feet/second... minimum or it will fall like a rock.

The way it works is, by the venturi principle, there is a VACUUM created above the wings, and the plane is sucked up into it.

Stop the vacuum and you stop the support, and you're left with 32 feet/sec^22 or 9.8 m/s/s

You're right. The plane needs wind flowing under it's wings continually, and the only way to get that is to keep moving. It's like riding a bicycle. You can only balance the bicylce if you pedal to move forward, and when you stop, unless you put your foot out, the bicycle will fall over.

There is a theoretic possibility, however, the head on wind speed

would have to reach the forward velocity of the aircraft.

in other words, if the aircraft is heading West at a speed of

600 miles an hour and it encounters a head wind of 600

miles per hour.it would be possible.

MERRY CHRISTMAS and have a nice day.

Thank you very much, while you're up