what if a person made a copter that was four large blades with a small cockpit in the middle. the blades would have pressurized tanks with exhausts to move them in a circle. the entire copter wound be placed on a giant pole with circular groves, like a screw. the copter would spin off the pole and fly. direction could be controlled by a rotating fan underneath. please comment on this.
-- weaselfan, Dec 15 2007

Fairey Rotodyne http://www.airliner...pen.file/1167871/L/
rotor-tip jets means no reaction torque, thus no tail rotor. [lurch, Dec 15 2007]

The Twenty-One Balloons http://en.wikipedia...Twenty-One_Balloons
a novel by William Pène du Bois, published in 1947 and awarded the Newbery Medal [baconbrain, Dec 16 2007]

(?) The Nazis did it. http://discaircraft...alcon.us/FOCKE1.htm
It's pretty much this exact idea, but it remains half-baked. [DIYMatt, Jun 09 2011]

Are the tanks pressurized with air?

Would the blades and the pole interfere with each other?

Why does the pole need helical groves?

I've seen a picture of a small 'copter with a small jet engine at the tip of each blade.
-- BJS, Dec 15 2007


//please comment on this.// This goes without saying. Punctuation and capitalization, however, are considered polite.
-- MaxwellBuchanan, Dec 15 2007


// pole be running right up through the middle // -> //copter wound//
-- lurch, Dec 15 2007


Sounds like the jet copter they have been trying to sell in the back of Popular Mechanics since I was a kid. I'll have to ind a link, but there are some good videos on Youtube of these things at night.
-- MisterQED, Dec 15 2007


//please comment on this.// Well, your writing is bad. I can't tell what you are proposing, really.

Tip-jet rotor helicopters have been around for a long time. They don't work well, usually, but they've been thought of and tried.

I have a balloon-powered helicopteroid toy that blows air out through the blade tips. That's what this idea sound like, in spots.

I once had another helicopteroid toy that had to be threaded down over a twisted metal strip, then pushed off violently with a plastic bushing to make it spin. That's what this idea sound like in other spots.

But I cannot put the two together for any reason.

As for a rotating fan underneath a rotor, it would be bad. Airflow into it would be disrupted, for one thing. For another, and worse, it would work against the natural motion of the helicopter.

If you aimed the fan to the left, say, it would push the helicopter to the right. But, being bottom-mounted, it would push harder on the bottom of the helicopter, causing a tilt. That tilt--top to the left, bottom to the right--would cause the lifting force of the rotor to pull the helicopter back to the left. That would likely more than cancel out any effect the fan had of causing the helicopter to move.

If, on the other hand, you put a fan above the rotor, it'd work better. A fan push to the right would tilt the rotor to the right, and off you go. (And airflow into the fan would be better.)
-- baconbrain, Dec 15 2007


Due to the trouble I had typing that day, I am truly sorry to the grammar police. Now, about the questions. The jets would be a small factor. I got idea out of a book (I forgot the title) where a man crashes his balloon on a small secluded island with a city of smart citizens. The kids devloped a ride similar to mine, but the propelers where moved by balloons upward, causing it to spin on the wheel. The characters also put the cockpits on the ends of the blades. You all had good ideas of problems I didn't think of. By the way, the jets will push the copter upward, causing it to spin on the pole. The jets could then again be angled to continue the spin. Baconbrain brought up intersting points, but I am not a avionics engineer and this was just in my imagination. I still want to hear what you guys (or girls) have to say.
-- weaselfan, Dec 16 2007


Thanks. I was wondering if you'd been reading that book. I can't remember the name of it, but it was great. I'll see if I can find it. (A fellow sets out in a balloon, a seagull punctures it, he ends up on a volcanic isle populated by French intellectuals whose kids have a balloon ride.)

In the book, the kid's multi-balloon ride did rise up off a spiral pole, but that was only for fun or varying the view. I don't think it would work well in reality. It also has nothing to do with a helicopter idea.

You and I remember it very differently, so I think you might be confused. It had no propellers anywhere. The balloons lifted, the twisted pole gave it a twirl. That's all, and I doubt that would have worked, anyhow.

[Later] The book is _The Twenty-One Balloons_ by William Pene Du Bois. It and his other works are marvelous reading for any Halfbaker. Please find and read.

Grammar police? Oh, [weasel], you have only heard from the coherence police. Grammar and spelling are touchy subjects for some folks here, but we are still trying to figure out what you are writing about. Some sort of handicapped helicopter is all I've been able to figure out so far. The spiral pole and the tip jets seem to be two different ideas, with the control fan as a possible third.
-- baconbrain, Dec 16 2007


Is this a toy or a real chopper?
-- RayfordSteele, Dec 17 2007


Either way, something's going to get chopped.
-- Alterother, Jun 10 2011



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