How does autorotation work in a helicopter?

How does autorotation work in a helicopter?

Autorotation is a condition of helicopter flight during which the main rotor of a helicopter is driven only by aerodynamic forces with no power from the engine. It is a manoeuvre where the engine is disengaged from the main rotor system and the rotor blades are driven solely by the upward flow of air through the rotor.

What are the 3 different regions for autorotation in order?

During vertical autorotation, the rotor disc is divided into three regions—the driven region, the driving region, and the stall region.

How do you descend a helicopter?

To descend, you simply revert the climb procedure: drop the collective (again, slowly) and the nose will drop. Lift will decreas and you’ll start descending. Again, try to refrain yourself from pulling the nose up. You’ll need to let the helicopter settle on the descend.

How does autorotation produce lift?

The rotational speed of the rotor system is held constant, and lift is created by increasing each rotor blade’s angle of attack. This is accomplished by raising the collective pitch control in the cockpit. Basic aerodynamic theory tells us that an increase in lift will be accompanied by an increase in drag.

What are the several factors affect the rate of descent in autorotation?

Several factors affect the rate of descent in autorotation: bank angle, density altitude, gross weight, rotor rpm, trim condition, and airspeed. The primary ways to control the rate of descent are with airspeed and rotor rpm.

How do you land a helicopter if the engine fails?

Actually, helicopters have a built-in mechanical control called the collective pitch lever that allows them to descend slowly and land even if the engine dies. This maneuver is called autorotation.

How do you make a paper helicopter template?


  1. Step One Cut your paper and draw guide.
  2. Step Two Fold section D along long dotted line.
  3. Step Three Fold Section C along long dotted line.
  4. Step Four Fold Section A along dotted line towards you.
  5. Step Five Fold Section B along dotted line away from you.
  6. Step Six Fold bottom edge of section C/D towards you.

What are the main parts of a helicopter?

The major components of a helicopter are the airframe, fuselage, landing gear, powerplant, transmission, main rotor system, and tail rotor system.

How does a helicopter change direction?

The rotor blades are pitched lower in the front of the rotor assembly than behind it. This increases the angle of attack — and creates lift — at the back of the helicopter. The unbalanced lift causes the helicopter to tip forward and move in that direction.

What is the collective control in a helicopter?

The collective pitch control (or simply “collective” or “thrust lever”) is located on the left side of the pilot’s seat and is operated with the left hand. The collective is used to make changes to the pitch angle of the main rotor blades and does this simultaneously, or collectively, as the name implies.

What is autorotation entry in a helicopter?

Autorotation entry covers the transition from normal, powered flight to steady autorotation. When the helicopter reaches a steady descent rate, forward speed and rotor speed, the entry is finished. The helicopter is now in steady autorotation. At this point, the pilot must identify a landing zone (LZ) and maneuver the helicopter to it.

What is 360 autorotation in helicopters?

360° Autorotation: If a suitable landing field is directly in front of the helicopter, but the helicopter is still too high to reach the landing field with a straight-in autorotation (i.e. would overshoot), a 360° autorotation can be used. The pilot just flies a 360° curve during the established glide phase.

What is autorotative descent in a helicopter?

Autorotation In a helicopter, an autorotative descent is a power-off maneuver in which the engine is disengaged from the main rotor disk and the rotor blades are driven solely by the upward flow of air through the rotor. [Figure 11-1]In other words, the engine is no longer supplying power to the main rotor.

How do you autorotation a 1111 8 helicopter?

11-8 Helicopters that do not have the throttle control located on the collective are generally exceptions to basic technique and require some additional prudence. The autorotation should be initiated with the power levers left in the “flight,” or normal, position.