# Helicopter Questions - Get Answers Now!

• sphynx_000
In summary: The ground actually falls faster than the elevator so in theory the helicopter would need more power to overcome the force of the ground.
sphynx_000
I know this is not as serious of a topic as you are all used to, but hopefully someone could help me out anyways?

- Imagine a helicopter hovering inside a cargo jet, (the jet is flying at cruising speed). What would happen to the helicopter if it was pushed outside the jet, with no changes being made to the controls. So if the main rotor keeps spinning at a constant speed... when the helicopter leaves the plane does it keep or lose altitude?

- Imagine a helicopter hovering in a elevator. If the controls in the helicopter are not touched, what happens when the elevator moves?

- If a helicopter is flying just feet off the ground, and the ground suddenly drops off (like a cliff), does the helicopter require more thrust to keep the same altitude?

any input would be appreciated!

sphynx_000 said:
Imagine a helicopter hovering inside a cargo jet, (the jet is flying at cruising speed). What would happen to the helicopter if it was pushed outside the jet, with no changes being made to the controls. So if the main rotor keeps spinning at a constant speed... when the helicopter leaves the plane does it keep or lose altitude?
If we're assuming that no damage was done to the aircraft, I'd say it would gain altitude due to the fact that there would be a large inrush of air. It would effectively be going from a standstill to whatever speed the jet was going very quickly which would cause it to gain altitude. Then again, if something breaks, it will lose altitude.

sphynx_000 said:
- Imagine a helicopter hovering in a elevator. If the controls in the helicopter are not touched, what happens when the elevator moves?
Think of it this way, the helicopter is hovering relative to the air in the elevator. If the elevator moves, so does the air in the elevator. I would think that the initial transient would cause the helicopter to drop a bit, but as soon as the acceleration dropped off, the helicopter would recover.

sphynx_000 said:
- If a helicopter is flying just feet off the ground, and the ground suddenly drops off (like a cliff), does the helicopter require more thrust to keep the same altitude?
It requires more power to maintain it's current altitude. It's called "flying in ground effect". It is a result of the increased circulation through the rotor disk due to the interaction with the ground. Usually ground effect is noticeable to about one rotor disk diameter above the ground.

This is the best discription of http://home.comcast.net/%7Eclipper-108/lift.htm" I have found so far. Helicopter blades use the same lift principle as an airplanes wing does, the volume of downwashed air is displacing the aircrafts load.

After a large cargo plane has moved through a volume of air there is a large downwash area left behind which will cause problems for any other aircraft in its wake, so to say. And there is also a condition called ground effect that would effect the helicopter after leaving the cargo bay. So I would think the helicopter would fall after being pushed out and this would increase its load and cause it to crash. The increased velocity from falling would need to be overcome by more thrust since the helicopter would experience more 'g' force or an increased load.

In a moving elevator I would guess the helicopter would experience inertia and react to the change in motion of the elevator. And as for the ground falling consider ground effect and atmospheric pressure changes.

Last edited by a moderator:

## 1. What is a helicopter?

A helicopter is a type of aircraft that is capable of vertical takeoff and landing, as well as hover and fly in any direction. It is powered by one or more engines that rotate the blades on top to create lift.

## 2. How does a helicopter stay in the air?

A helicopter stays in the air by using the lift generated by the rotation of its blades. The blades are designed with an airfoil shape, similar to the wings of an airplane, which creates a difference in air pressure, causing the helicopter to rise and stay in the air.

## 3. What are the main components of a helicopter?

The main components of a helicopter include the main rotor, tail rotor, engine, cockpit, and landing gear. The main rotor and tail rotor are responsible for lift and control, while the engine provides power. The cockpit is where the pilot sits and controls the helicopter, and the landing gear supports the helicopter during takeoff and landing.

## 4. How do helicopters differ from airplanes?

Helicopters differ from airplanes in several ways. The most significant difference is that helicopters can take off and land vertically, while airplanes require a runway. Helicopters also have the ability to hover and fly in any direction, while airplanes can only fly forward. Additionally, helicopters have a different design and use different flight controls compared to airplanes.

## 5. What are some common uses for helicopters?

Helicopters have a wide range of uses, including transportation, rescue and emergency services, military operations, and aerial photography. They are also used for firefighting, news reporting, and tourism. Helicopters are a versatile aircraft and can access areas that are difficult for other types of aircraft to reach.

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