Why is it that helicopters maintain there height when they fly over the edge of a cliff and don't plummet?

Answer 1

It's because they are flying. Helicopters do not fly by pushing air down against something. Each blade of the rotor is a wing which generates lift, just like the wings of an ordinary, fixed-wing aircraft. Fixed wing craft generate the lift by forward motion which increases the airspeed over the surface of the wing, helicopters do it by rotating the wing quickly through the air. They get THEIR forward motion by altering the angle of the rotors.

Answer 2

The helicopters rotors are pushing against the air in which it is travelling, not the terrain below, so it doesnt make any difference to the helicopter what is underneath the air in which the helicopter is travelling.

Sometimes turbulence in the air will cause the helicopter to rise or fall in the air at eg a cliff edge where rising or falling currents of air could push the helicopter up or down.

Hope this is a simple enough answer to quite a complex question

Answer 3

because the helicopter unlike the hovercraft does not glide over land , the same values of gravity applies on the top of the cliff as it does over the side of the cliff. so there is no reason the helicopter would plummet , unless there is a downward gust of wind at the end of the cliff, this would cause pressure above the helicopter. the pilot would have to compensate for the down draft.

Answer 4

The helicopter blades are pushing against the air not the ground. The fact that the helicopter has just flown onver the edge of a cliff just means that there is a greater depth of air to push down on.

Answer 5

A few interesting answers on here!

A little lesson to begin. The air on earth has resistance based on it's height above sea level. As you move higher in the atmosphere the air becomes thinner.

The answer, a helicopters blades revolve at higher speeds the higher they are. Therefore, the ground below does not generate the resistance used for lift, the actual air does. Helicopters don't push themselves up, they pull themselves up.

Answer 6

Because they are rotary wing aircraft, not ground effect hovercraft. Remember: helicopters don't FLY-- they BEAT the air into SUBMISSION!

Seriously. Aircraft wings don't cause a vacuum that sucks the aircraft UP into it. They push the air DOWN and the aircraft goes up by reaction. You can see what happens with the prop wash-- the blast of air forced down, and dirt and litter get forced out in all directions. The same thing happens with a fixed wing aircraft, only it goes over and you don't notice it as much. If a small fixed wing plane was to do tight circles, you would see something analogous to the prop wash.

A helicopter can fly up to its service ceiling, where it can't get enough air for its engines or where it can't force down enough air to hold itself up; whichever comes first.

For most of the history of aviation, there was a belief in a mythical force called 'lift', which lifted the plane. This has now been shown to be false; it is like the ether for propagation of light, or centrifugal force. There is no centrifugal force; there is only centripetal acceleration. We now know that aircraft wings work by action and reaction; they force air down and the aircraft is forced up.

Answer 7

The rotors on a helicopter are actually wings. Instead of moving forward like the wing on a plane would to to generate lift, the wing on a helicopter just moves around in a circle. The motion of the wing "cuts" through the air causing the air beneath the wing to have a greater pressure thus, lifting the wing, and anything attached to it.

Answer 8

It is not the wind pushing the ground that maintains it in air. It is the Pulling on the atmosphere above it.
During "lift off" the combination of the wind pushing down on the earth and the helicopter pulling the air from above helps it defy gravital hold. once in the air it mainly uses the pulling down of the air to defy gravity. not pushing the air to the ground. and within its design is a series gyrospheres to maintain stabiliy once in the air.

Hovercrafts push air to the ground to defy gravity and friction. they will plummet,

look at the similaries between hovercrafts and helicopters.
Both have propellers or fans both have stabilizers strong engines or motors and use air to force movement.. now look at the area the propellers covers in contrast to the proportion or size of the machine it is designed to move. helicopters are significantly smaller the the area the propellor will rotate. because the pulling of the air is greater than the mass of the helicopeter it lifts or is pulled off the ground. while the area of rotation of the Propellor in the hovercraft is smaller than the mass of the hovercraft itself than it is heavier than the pull so it is the pushing that is the stongest force and uses a curtain to hold the air underneath to defy gravity. it too uses gyropheres to maintain stability.
MAX

Answer 9

Because a helicopter's motor works against the force of gravity. It doesn't push it up from the ground. So once it attains sufficient speed to lift itself from the force of gravity, then it doesn't matter how far it is off the ground.

Answer 10

Same reason they don't plummet over land