| Chris Palmer | 17 May 2013 12:01 p.m. PST |
My friend Norman Dean sent me this link regarding plans for an experimental Confederate helicopter. I had never heard of it before. link I would love to see some manufacturer make a gaming model of this!
|
 Parzival  | 17 May 2013 12:14 p.m. PST |
Holy cheese— how did this get kept secret so long? Clearly, we need working models!  |
| 15mm and 28mm Fanatik | 17 May 2013 12:18 p.m. PST |
Chances are if it was built, it would never have flown the way it's supposed to. It wasn't until 1912 when an experimental model (by Danish aviator Jacob Christian Ellehammer) enjoyed any form of success at all. I think they filmed it and it was in the opening sequence of some TV show I watched as a kid, but I can't remember what it was. |
| firstvarty1979 | 17 May 2013 1:18 p.m. PST |
It would have done fine on a planet with much less gravity than Earth has. |
| Royal Marine | 17 May 2013 10:40 p.m. PST |
I think Mr HG Wells test piloted one on Mars on behalf of the CSA. |
| DrVesuvius | 18 May 2013 9:57 a.m. PST |
Hmmmmm I wonder if anyone's ever managed to get anything to actually fly using that Da Vinci style airscrew. I'm not talking a viable aircraft, just a proof of concept model. Anyone know? |
| EJNashIII | 18 May 2013 12:11 p.m. PST |
I don't think it is possible. You would need a far thicker atmosphere for something like that to actually work. Maybe on Venus. |
| tsofian | 18 May 2013 12:42 p.m. PST |
In HQC it will work on Mars, as it has a very thick atmosphere and 1/3 the gravity Terry |
| Lion in the Stars | 18 May 2013 2:02 p.m. PST |
I'm not sure an Archimedean screw will work with any 'atmosphere' thinner than water. A prop (airscrew to the Brits) uses Bernoulli's lift. |
| Parzival | 18 May 2013 9:13 p.m. PST |
A prop (airscrew to the Brits) uses Bernoulli's lift. Physicists now argue that propellors and airplanes aren't using any sort of "lift" at all— that it's a myth. The claim is that it's nothing more radical than a pure Newtonian action-reaction result, with the forward (or upward) motion produced simply by the act of deflecting air in the opposite direction. A good example would be when you hold your hand outside the window of a moving car. Your hand is not shaped like an airfoil at all, but at certain angles it will be forced upward by the air impacting against it, just as the wing of an airplane (or the blade of a propellor) is forced into motion. Alter the angle, and it will be forced downwards. Pure Newton. Here's more on the subject: link Not sure what bearing it has on the Archimedean screw concept. |
| DrVesuvius | 19 May 2013 3:30 p.m. PST |
I know, I was shocked to learn recently that what I was taught as accepted fact about the principles of flight was now merely a debated (and partially debunked) theory. Blimey, next thing they'll be telling us that the brontosauruses didn't drag their tails on the ground and that Pluto isn't a real planet. |
| tsofian | 19 May 2013 5:30 p.m. PST |
There aren't even brontosaurus anymore! Terry |
| J Womack 94 | 20 May 2013 11:55 a.m. PST |
Pluto is a real planet, I don't care what those so-called scientists say! |
| John the Greater | 20 May 2013 1:39 p.m. PST |
Pluto is a real planet No, Pluto is a dog. And not a very good one at that. The story on the Confederate helicopter is great. It could be a nice add-on to any VSF scenario. |
| tsofian | 20 May 2013 5:11 p.m. PST |
I will not have Mickey Mouse's dog maligned on this forum! |
| Lion in the Stars | 20 May 2013 6:37 p.m. PST |
From Parzival's link:
Note that helicopter rotor blades are basically flat wings in a steep angle. The mechanism by which they form lift is exactly the same. Rotor blades are usually not airfoil-shaped or tear-shaped because drag is less of a concern. On the other hand, the angle of attack of the blade is very critical because the vertical lift of the helicopter is controlled by changing the angle of the blades. In this case flat blades might even work better for this purpose than airfoil-shaped ones would. Wow. Dunno what to say about that, but bovine excrement. Every single rotor blade is an airfoil shape. Many of them are close to symmetrical, so that the blades can be 'flattened' to make no lift, and even be turned so that the air rising through them makes them spin faster (critical for autorotation). The exact angle of attack needed for zero lift varies with the helicopter design. You can get away with flat plates in models because the Reynolds Number (relative viscosity of the air) is different. The air around insect wings is closer to light oil in terms of behavior than what we think of as 'normal' for air! |
| CAPTAIN BEEFHEART | 22 May 2013 3:00 a.m. PST |
I just think it looks cool! |
| surdu2005 | 31 May 2013 11:35 a.m. PST |
I think it's awesome, but where does the crew fit? Where can I put my Nordfeldt? Where is the Varga-style nose art? :) Seriously, this is a great model. I'd love to know how the "screws" were made. Buck |
paints a couple of mean-looking mutant-type villains from the far future.