Comments on: Copter Cops (Nov, 1958)

By: alex in Las vegas

alex in Las vegas — Sat, 13 Jun 2009 15:53:14 +0000

can any one tell me if a Flying platform can fly with only One prop../ I thoght you need two counter rotating to counter Torq..?
Vertipod – Pete bitar has a great platform now and only uses One (1) prop for lift../
all others needed two..
looking forward to hearing the correct annswer/
alex in las Vegas lasvegasak2@aol.com

By: Mike

Mike — Thu, 15 Jan 2009 00:21:49 +0000

I wouldn’t call it “gently”

By: Toronto

Toronto — Wed, 14 Jan 2009 02:58:00 +0000

Mike – you mean it autorotates gently to the ground?

By: Mike

Mike — Wed, 14 Jan 2009 02:40:38 +0000

Myles ,
What happens when one engine quits?

The same thing that happens when one engine quits on a standard helicopter.

By: MrG

MrG — Tue, 13 Jan 2009 21:07:02 +0000

Come to think of it, I have seen a helicopter with three rotors, or at least a model of one. Familiar with the Mil Mi-26 “Halo”, the world’s biggest production helicopter? Nice YouTube video at:

http://www.youtube.com/watch?v=MKpMEzPBH5o

Looks like Mil promo video … there’s a great shot of one hauling a damaged Chinook around like it was a toy:

http://www.aerospaceweb.org/qu.....i26_01.jpg

Anyway, the Russkies like to build big, and Mil came up with a concept called the “Mi-32″ that looked like three pipes linked in a triangle, with the forward section of the Halo tacked on front and the dynamic system of the Halo mounted on top of each vertex of the triangle:

http://www.aviastar.org/helicopters_eng/mi-32.php

The Russkies weren’t crazy enough to build it, so I couldn’t say it was validation for Tinsley. I more than easily concede that he had a “Tom Corbett Space Cadet” concept of design.

Cheers — MrG / http://www.vectorsite.net

By: MrG

MrG — Tue, 13 Jan 2009 20:46:24 +0000

There are plenty of still pix of the AirGeep and Pawnee free-flying, one with the Pawnee at about
100 feet — plus YouTube videos of the “AirGeep” and “Hiller Pawnee” free-flying, if not very aggressively. As far as engine-out, multiengine helicopters usually have two (sometimes three) engines driving the same transmission system. Of course that’s a necessity for a single-rotor helicopter, but it’s also so with twin-rotor helicopters like the Chinook. It is not unusual for the
sum of the power of the engines to exceed the capability of the rotor system downstream, with the engines fitted with limiters. When an engine goes out, the remaining engine can be run at full rated power.

The AirGeep had twin engines with a common transmission. I have heard the initial version was so underpowered it was stopped in a demonstration by a fence. “Well, we’ll be OK as long as the enemy doesn’t put up fences.”

As far as three rotors go, got me there sport. Didn’t think of that, never saw any rotorcraft with three main rotors.

By: Myles

Myles — Tue, 13 Jan 2009 19:27:47 +0000

Did flying platforms fly pretty well? I looked at the link, but most multi-engine ducted fan models never got beyond the tethered flight stage. How do you balance the output of 3 engines without computer control? What happens when one engine quits?

By: rsterling78

rsterling78 — Tue, 13 Jan 2009 13:26:06 +0000

It looks like our low-flying copter cops have created so much of a distraction that they’ve caused a motor vehicle accident.

By: MrG

MrG — Tue, 13 Jan 2009 12:36:39 +0000

Flying platforms actually flew pretty well — see:

http://www.vectorsite.net/avplatfm.html

They just didn’t have enough advantages over helicopters to be worth the bother. The idea was popular at the time and Tinsley wasn’t unusual in pushing it.

Cheers — MrG // http://www.vectorsite.net

By: Sean

Sean — Tue, 13 Jan 2009 12:27:06 +0000

It wouldn’t be nearly as futurey looking.

By: Eamon

Eamon — Tue, 13 Jan 2009 04:27:49 +0000

I thought the army abandoned the idea of a flying platform because it was inherently unstable. And what’s wrong with just using a helicopter?