Can Helicopter Pilots Perform Dead-Stick Landings Through Autorotation?

  • Thread starter Ivan Seeking
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In summary, dead-stick landings are practiced by helicopter pilots as part of their training and certification process. These landings, also known as autorotations, involve shutting off the engine and using the kinetic and potential energy of the rotor blades to safely land the aircraft. The blades must be maintained at a specific RPM to avoid stalling or departing from the rotor hub. This type of landing is not a violent event and requires quick reaction time from the pilot. It is a necessary skill for helicopter pilots to have in case of engine failure.
  • #1
Ivan Seeking
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Are dead-stick landings ever practiced, or are they only used during a legitimate power-plant failure?

Someone once told me that some breed of helicopter pilots have to perform a dead-stick landing before getting certified. Is that true?
 
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  • #2
Yes. Absolutely.

We used to do autorotations for every maintaiance test flight as well as other things. The Army did institute a policy at one time that autorotations were not take to the ground but started at around 10,000 MSL down to some altitude which was treated as the ground. I don't know if they still do that or not.

Despite the connotation, the act of an autorotation is not a violent or drastic event. Granted, the sound of engines going off-line is very un nerving the first few times you hear it. If you were to watch an autorotation being practiced, and it were done properly, an untrained eye might not even be able to tell it was happening.
 
  • #3
I saw on discovery(or mega structures on NGC), that in case of engine failures, pilots are trained to get the heli down by letting the blades wind mill(& hence create drag & slow the thing down)
 
  • #4
ank_gl said:
I saw on discovery(or mega structures on NGC), that in case of engine failures, pilots are trained to get the heli down by letting the blades wind mill(& hence create drag & slow the thing down)

Hint: That's called autorotation, what this thread is about...
 
  • #5
Mech_Engineer said:
Hint: That's called autorotation, what this thread is about...

:shy:really??

How come I didnt notice that while posting:grumpy:

:tongue:
 
  • #6
Also, the blades don't "create drag" on autorotation. That would inevitably slow the blades down, cause them to stall, and crash the helicopter.

In autorotation, the blades simply balance kinetic energy and potential energy. Too much kinetic energy and the blades depart the rotor hub. To little kinetic energy and the blades stall and stop spinning (unrecoverable situation). The right balance is a range of RPM which the rotor blades must be maintained (usually the fixed RPM the blades spin in regular flight). The reaction time of an engine failure for a pilot is on the order of 1-2 seconds that he/she has to lower the collective before blade stall occurs. Its a very unforgiving situation.
 
  • #7
One of the fellows that I know is a pro chopper pilot (and I'm going to take an indroductory flight lesson just so I can have that experience under my belt). He definitely had to practice engine-failure landings before being licensed. That's here in Canukville, though—I don't know the laws elsewhere.
 
  • #8
Another way to understand it is that during autorotation the blades have negative pitch near the hub and causing windmill effect as the a/c drops, transfering aerodynamic loads into rotational momentum in the rotor head. To land, the pilot pulls collective putting positive pitch on the blade tips, transfering rotational momentum to thrust.
 

What is autorotation in helicopters?

Autorotation is a technique used by helicopter pilots to land safely in the event of an engine failure. It involves using the upward flow of air through the rotor blades to maintain lift and control the descent of the helicopter.

How does autorotation work?

During an autorotation, the pilot will reduce the pitch of the rotor blades to decrease drag and increase the rotation speed. This allows the rotor blades to continue generating lift even without engine power. The pilot can then use the cyclic and collective controls to control the direction and rate of descent.

Is autorotation dangerous?

Autorotation is a standard procedure taught to all helicopter pilots and is considered a safe technique for emergency landings. However, it does require skill and training to execute correctly, and the outcome of an autorotation landing may vary depending on factors such as altitude and wind conditions.

Why is autorotation important for helicopter safety?

In the event of an engine failure, autorotation allows the helicopter to continue flying and provides the pilot with a controlled descent to perform a safe landing. Without this technique, an engine failure could result in a catastrophic crash.

Are there any limitations to autorotation?

Autorotation is not possible in all types of helicopters, such as those with coaxial rotors or rigid rotors. Additionally, the success of an autorotation landing depends on factors such as altitude, airspeed, and wind conditions. Therefore, it is important for pilots to continually train and practice this technique to ensure they can perform it effectively in an emergency situation.

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