How does a helicopter lose altitude?

Once the collective has been lowered and the engine set to flight idle, the helicopter will lose altitude.

What are the corrections for retreating blade stall?

Flight performance during a retreating blade stall Recovery involves lowering the collective pitch, relieving forward pressure on the cyclic or more commonly, both. Either of these control movements should restore the proper attached airflow over the retreating blade thus generating lift again.

How a helicopter gets lifted in air?

Wings create lift because of a relationship called the Bernoulli Principle. A helicopter’s rotor blades are wings and create lift. An airplane must fly fast to move enough air over its wings to provide lift. A helicopter moves air over its rotor by spinning its blades.

What are the forces acting on a helicopter hovering above the ground?

There are four forces acting on a helicopter in flight. They are lift, weight, thrust, and drag. See figure 2-1. Lift is the upward force created by the effect of airflow as it passes around an airfoil.

What happens to a helicopter when it loses lift?

If lift exceeds weight, the helicopter accelerates vertically until the forces are in balance; if thrust is less than drag, the helicopter slows until the forces are in balance. As the helicopter moves forward, it begins to lose altitude because lift is lost as thrust is diverted forward.

Why do helicopters rotate at high altitude?

When the helicopter gains altitude vertically, with no forward airspeed, induced airflow is no longer restricted, and the blade tip vortices increase with the decrease in outward airflow. As a result, drag increases which means a higher pitch angle, and more power is needed to move the air down through the rotor.

Why is weight important in helicopter performance?

Weight is one of the most important factors because the pilot can control it. Most performance charts include weight as one of the variables. By reducing the weight of the helicopter, a pilot may be able to take off or land safely at a location that otherwise would be impossible.

What is the minimum angle of descent for a helicopter?

In theory, a pilot has a choice in the angle of descent varying from a vertical descent to maximum range, which is the minimum angle of descent. Rate of descent is high at zero airspeed and decreases to a minimum at approximately 50–60 knots, depending upon the particular helicopter and the factors just mentioned.