Move over Plane on a Treadmill there's a New Sheriff in Town

[Father Time]

Helicopters do not have "thrust" that contributes a major amount of motion from the engines. It is residual thrust, and incremental in pretty much all cases. The main purpose of the engines on a helicopter is to turn the rotors (main and tail, which are often connected via a driveshaft).

The main foward thrust for a helicopter comes from manipulating the angle of attack of the rotor blades.

Here is a less complicated version of what I was trying to explain:

http://www.centennialofflight.gov/es...pitch/DI39.htm

How they work overall:

http://travel.howstuffworks.com/helicopter.htm

Yeah, I kind of shot myself in the foot on this one. I researched it AFTER I had posted. I was in the mindset of the helicopter "staying" on the pad, then lifting off. I rushed into that answer.

I understand what you mean. (That is way when the helicopter moves forward the front tilts) Good links though.

[cp[mike]]

lol AWESOME

[accord2nr81]

it depends on if the table is spinning in the same direction as the blades on the choppa or in oppisite... i say it would take off going oppisite direction and would crash and burn if spinning in the same

[MikeW]

Let the Games Begin!!

Way to go npor...lets just hope it doesnt take as long for Mythbusters to get ahold of this one as it did for "plane on a treadmill"



What? My opinion? Shit...i had a hard time wrapping my brain around how the damn plane took off...now you want me to get into this?!?

Ill just shoot in the dark and say "Plausible" If the blades/table are moving in the SAME direction -- NO. If theyre moving in OPPOSITE directions, i say its possible, but controlling the "choppa" will be difficult, if not impossible.

[cp[mike]]

if it were spinning opposite directions, then both the propeller and the base of the turntable would be stationary, while the body of the chopper and the round part of the table would be spinning... of course it wouldnt take off that way, it would probably just wreck the chopper due to centrifugal force.

if they were spinning the same direction, they would only need to run the chopper's prop half as fast, as the rest of the work is being done by the turntable. that would be enough to get the prop spinning enough to get lift, but the moment the chopper separated from the turntable, it would be all over, as the chopper is now in the air while spinning very fast. until the tail stabilizer prop was able to hold the chopper straight, it would continually lose its lift, but then its back on the turntable spinning again. so no, it would just sit there, spinning, and spinning...

[deevergote]

It probably wouldn't come back down straight, if it were able to achieve lift. It probably WOULD take off, but it wouldn't stay airborne simply because of the lack of stability. Unless, of course, it falls apart first.

[foamypirate]

Let's put wheels on it...

[Father Time]

Let's put wheels on it...

[MikeW]

does it have to be an Apache style "choppa"? What if it were a sikorsky S-64 Skycrane??

[203Cree]

Please die. Please.

Assuming that the aircraft has either a tail rotor or a counter rotating rotor system, such as a Chinook or Sea Knight (and newsflash, all helio's do), as long as you can keep it from flying off the turntable, then yes it would take off no matter wich direction the turntable was spining. However, centrifugal force would be a great factor to try and over come, and in all reality this is probably one of the dumbest, most asinine things I've ever seen posted on the interwebs.

[F22HB]

Trick question. Don't turn the dj table or anything, and let the helicopter take off just like normal. I think everyone just likes to overthink this stuff,lol. Who cares what its on?

[owequitit]

Please die. Please.

Assuming that the aircraft has either a tail rotor or a counter rotating rotor system, such as a Chinook or Sea Knight (and newsflash, all helio's do), as long as you can keep it from flying off the turntable, then yes it would take off no matter wich direction the turntable was spining. However, centrifugal force would be a great factor to try and over come, and in all reality this is probably one of the dumbest, most asinine things I've ever seen posted on the interwebs.

Nah ah.

[deevergote]

Is this hypothetical situation assuming that the center of the turntable is aligned with the center of the main rotor?

[blizzard335]

does it have to be an Apache style "choppa"? What if it were a sikorsky S-64 Skycrane??

that will lift the turntable along with it

[owequitit]

Hypothetically, the helicopter still has the independent ability to fly, but beyond a certain speed, it would be impossible to control and the airframe would exceed its structural limits, which I have no idea what the G limits are on a helicopter.

But assuming you had a pilot that could handle it, and the helicopter actually lifted off, then the rotation would slow as soon as it got off the ground, and the helicopter would resume normal flight.

The question is, how fast is that turntable spinning?

I am guess this was created by someone who was butthurt about the airplane on a treadmill thing.