I know this isn’t modeling related but, I figured this would be the best place for all my fellow “Helo-nuts” to read it.
This is suppose to be a true story. Enjoy.
A Huey Cobra practicing autorotations during a military night training exercise had a problem and landed on the tail rotor, separating the tail boom. Fortunately, it wound up on its skids, sliding down the runway doing 360s in a brilliant shower of sparks. As the Cobra passed the tower, the following exchange was overheard:
Tower: “Sir, do you need any assistance?”
Cobra: “I don’t know, tower. We ain’t done crashin’ yet!”
this is the most retarded question anyone could ask in the helo forum but what is autorotation? is it when the engin is shut off but the helo’s rotors are still spinning because of the air pushing up when falling? and by the time you reach the ground, you have enough lift for a safe landing?
I read that in a canadian paper airplane book[:D]
I meant no offense what soever to the people with an actual mental retardation
You basically have it. The idea is to allow the blades to spin with no power from an engine failure etc. The spinning blades will allow for limited control and also (in theory) soften your landing/crash since they are still providing limited lift. Usually though, it is still a very hard landing that breaks the aircraft and crew. However, most crew do survive autoration landings.
Yep, that’s about it. The idea is, when you lose power, you bottom out your collective (the control on your left hand that controls the pitch of the rotor blades). This flattens the pitch on the blades and allows them to keep spinning using their own inertia. When you’re a short distance above the ground, you pull full-up on the collective, making the blades bite into the air, effectively slowing you down and lessening the impact. It is basically a controlled crash, but it does save the crew!
The Autorotation it self is explained good enough, but the end of it?
What we do when we practice engine failures, we lower the collective all the way, and use it to maintain the rotor RPM at a proper rate. A little up on the collective will slow it down some, all the way down and doing brisk turns will bring the rotor RPM up a little.
At the bottom (50 to 100 feet above your selected landing area) you start a flare by gently pulling back on the cyclic stick (in your right hand). This will slow down you speed and your rate of descent, and increase the rotor RPM to the maximum recommended (red line). When the aircraft is slowed down sufficiently, you again push the cyclic forward and let the aircraft settle towards the ground, just before it touches, you will pull up on the collective sufficiently to slow down to a smooth landing.
In flight schools we do this to the ground almost every day, and it does not have any detrimental effect on the aircraft. Actually, sometimes an autorotational landing can be smoother than a regular landing!
In real life, the outcome of the landing is usually dependent on the reaction time of the pilot, and the landing area he chooses, but in general, if chance favours our “hapless pilot”, he or she should be perfectly able to set the machine down, without damaging the aircraft or hurting the passengers or crew.
Hope that helps!
(Oh, I’m a helicopter pilot/Instructor pilot)[:D][;)]
Sure Shark,
But if you are flying at night, in a storm, over unfamilair terrain and the motors give up the ghost, you have nanoseconds to react, and choose your landing area, not some nice field of concrete or grass.
And wouldn’t it make you mad if your nice, dark flat landing area, suddenly turned on some lights and you found out you were going to land on a house?
Full autos to the water are fun, or used to be until they got rid of the boat hulls, now it’s a crash into the water.
As one of my good friends used to say, “the first few seconds are devoted to panic, then either God takes over or he doesn’t. . .”
Actually, if you are in a turbine machine, it is critical to do the right thing immediately, but once you do, it should be no problem getting the machine down safely, unless of course you are over terrain that does not allow a safe landing. But, and it is a BIG but, any pilot worth his pay should be able to Autorotate the machine down to the ground from any altitude he’s flying from, if not, the flight was not planned well!
I hate to nitpick the original joke, but does anyone else find that scenario unlikely? lol.
With the Cobra’s narrow profile and landing gear, you’d think it would either flip over or collapse the skids before it started doing 360’s down a tarmac. I dunno, just thought it sounded a little weird. I know it’s just a joke, and I’m probably looking too much into it, lol.
A helicopter is a complex assemblage of advanced mechanisms working in oppostion to one another and carefully arranged around a hydraulic leak. They don’t fly … they beat the air into submission.
Yea, but they’re fun to fly in and I agree a good pilot can auto-rotate safely almost anytime. I should add that I only flew once with a bad pilot(if I had a choice)
Shark, the big BUT is terrain, followed very quickly by whatcha doin’.
Mean old Mr. Gravity likes to take over at precisely the wrong time.
Leaving the deck of a ship, coming back to the deck of the ship. . .in the Bering Sea, pulling pitch with a sling load at 25’, Fat dumb and happy over a forest at 100’ looking for a lost hunter, or looking for ice fishermen on a floe too thin to support the weight and you have, no matter how quick you catch it, a mess on your hands.
And you always have to remember that some helos behave better in an auto than others. Helicopters are really no different that a fixed wing in that some “glide” better than others. I love the Blackhawk but I have to admit that it has a great affinity for the ground when you lose power. Our glideslope is somewhat like a brick with a pinwheel on top.
… and the schweizer 300C is like a Greased ANVIL!!![:D][:D][:D]
But they are agile and good to fly, and Auto’s to the ground are a hoot.
I do agree that when the fertilizer hit’s the propeller, it’s nice to be over a flat, level area, but even if the donk quits at the most inoportune time, you still have a chance to live (As they say, fly it till the last bit stops!)
Oh and by the way, a helicopter does not fly, it vibrates so much that the ground repells them![:D]