Answer :
The Earth, the air, and the airplane all move as one. To fly east to west with a ground speed of zero, you need to fly into a wind that is strong enough to allow the airplane to fly, because the airplane must always be moving with respect to the air around it.
If you are outside the atmosphere, the rules change. For example, geosynchronous satellites orbit at a speed that keeps them over the same spot on Earth at all times. That's possible because they don't have to deal with an atmosphere that is moving at the same speed as the Earth's surface. For an airplane to do that, however, it would have to actually fly through the atmosphere at high speed.
Depending on the aircraft and latitude, it's possible to fly west at a speed that keeps the aircraft motionless with respect to outer space, while the Earth and atmosphere move past it. But the opposite cannot be done—you can't fly east at a speed that keeps you at the same spot above the Earth, because the atmosphere is moving east with you, and you need to be moving forward with respect to the atmosphere. If you had enough of a headwind, you could do it, but headwinds strong enough for that don't exist (there isn't any place on Earth with a 1000-mph headwind that you could use for this purpose along the Equator, for example).
Answer :
If you are outside the atmosphere, the rules change. For example, geosynchronous satellites orbit at a speed that keeps them over the same spot on Earth at all times. That's possible because they don't have to deal with an atmosphere that is moving at the same speed as the Earth's surface. For an airplane to do that, however, it would have to actually fly through the atmosphere at high speed.
Depending on the aircraft and latitude, it's possible to fly west at a speed that keeps the aircraft motionless with respect to outer space, while the Earth and atmosphere move past it. But the opposite cannot be done—you can't fly east at a speed that keeps you at the same spot above the Earth, because the atmosphere is moving east with you, and you need to be moving forward with respect to the atmosphere. If you had enough of a headwind, you could do it, but headwinds strong enough for that don't exist (there isn't any place on Earth with a 1000-mph headwind that you could use for this purpose along the Equator, for example).
Answer :
With given conditions of gravity and the movement of the earth about it's axis and the concept of the atmosphere moving with it, makes your theory possible... a plane can fly at 0kph with respect to the speed of earth's rotation (relative velocity)...
Answer :
What you are really asking is 'is it possible for an aircraft to maintain a geostationary orbit?' The answer is yes. Typically at low altitudes this is done using a helicopter.
It is virtually impossible to achieve this using a fixed wing aircraft as the lift in an aerofoil is created by the wind moving over the surface and creating high pressure below it and low pressure above it. The further away you move from the earth's surface, the lower the gravitational pull and the greater the forward speed required in order to maintain a geostationary orbit, however, the density of the air is also reduced so the amount of lift available to an aerofoil is also reduced. The catch is that the air is neither stationary nor moving at a constant velocity. Moreover, the direction changes. Thus it is not reliable as a means of providing constant even lift.
Satellites manage to keep a geostationary orbit by flying at an altitude where the forward motion compensates for the downward motion due to gravity. Eventually, friction from the extremely thin atmosphere will eventually slow them down and unless corrected by booster rockets, they would eventually fall to earth, or burn up in the atmosphere.
Answer :
Answer :
What you are really asking is 'is it possible for an aircraft to maintain a geostationary orbit?' The answer is yes. Typically at low altitudes this is done using a helicopter.
It is virtually impossible to achieve this using a fixed wing aircraft as the lift in an aerofoil is created by the wind moving over the surface and creating high pressure below it and low pressure above it. The further away you move from the earth's surface, the lower the gravitational pull and the greater the forward speed required in order to maintain a geostationary orbit, however, the density of the air is also reduced so the amount of lift available to an aerofoil is also reduced. The catch is that the air is neither stationary nor moving at a constant velocity. Moreover, the direction changes. Thus it is not reliable as a means of providing constant even lift.
Satellites manage to keep a geostationary orbit by flying at an altitude where the forward motion compensates for the downward motion due to gravity. Eventually, friction from the extremely thin atmosphere will eventually slow them down and unless corrected by booster rockets, they would eventually fall to earth, or burn up in the atmosphere.
Answer :
In theory. . . .
If you were flying into a headwind that was at a sustained and steady speed that was sufficient to move enough air across the wings to provide the needed lift, then you would not need to change position relative to the ground - 0 ground speed.
The problem is that the wind is not usually steady at a single, high enough speed, and, if going fast enough, is unlikely to be smooth.
That scenario would be much more likely with a small private plane that does not need a very high wind speed for the necessary lift.
Answer :
If you were flying into a headwind that was at a sustained and steady speed that was sufficient to move enough air across the wings to provide the needed lift, then you would not need to change position relative to the ground - 0 ground speed.
The problem is that the wind is not usually steady at a single, high enough speed, and, if going fast enough, is unlikely to be smooth.
That scenario would be much more likely with a small private plane that does not need a very high wind speed for the necessary lift.
Answer :
Yes. The aircraft must fly into a headwind equal to the speed of the aircraft and sufficient for the aircraft to remain aloft. By this I mean that if the stall speed of the plane is 100 miles/hour, the plane needs to fly into a headwind of at least 100 miles/hour but less than the maximum speed of the plane. In this way, the speed of the plane relative to the Earth will be zero.
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