Why a flying saucer?

**weed_eater_guy** · 05-12-09, 10:33 AM

A chain of thoughts occurred to me and I'm wondering what yall think:

A show on the History Channel (I think) was talking about conspiracy theories behind the Nazis and then the U.S. Air Force secretly developing flying saucers, apparently just for the damned sake of making an aircraft with a circular wing platform, which, as one about to graduate with an Aerospace Engineering degree, I can say is just about worthless for subsonic flight (aspect ratio is extremely low) and crap for supersonic flight (a blunt leading edge would make a lot of drag and sonic boom at those speeds). So, for a while I was thinking, why the hell would anyone, let alone any alien species, make a saucer-shaped craft? In what way would it actually make sense?

Another thought occurred to me that I looked up and, sure enough has a bit of validity according to some:

http://euclid.colorado.edu/~ellis/Re...s/WaDrAnGr.pdf

The idea is that, well, if a warp drive can shrink and expand space in front of and behind a spacecraft, respectively, and a mass the size of earth can shrink space below us just a little bit (gravity), wouldn't a correctly-oriented warp drive be usable as an anti gravity device? This would be extremely elegant for a spacecraft: a single propulsion system doing just about everything. No need for extra thrusters or anything, just a warp drive, and a power source, and that would get you to a planet, poke around a bit, land, mark "___ was here!", take off with a couple cows, and go home.

So on thinking of that, I thought about all those pics of how a warp drive is supposed to work:

http://www.naznet.com/community/atta...1&d=1237508894

Notice how the ship is inside a very clean, uniform bubble of undistorted space wrapped by sharply warped space? Somehow, I doubt a warp drive would actually make such a clean, nice warp field like this. If the field is anything like any gravity field, magnetic field, whatever, there would probably be at least some distortions very near to the engine itself, putting undue stresses on the spacecraft's structure and such. I'm sure there will be ways to delay the warping of space till a certain point away from the warp drive, but nevertheless, the idea of a perfect warp field like this goes against instincts: the warp field will probably be just slightly screwed up as a best-case scenario, and if you're warping the crap out of space to go many dozens of times the speed of light, this slight amount of warping might become a significant concern to the spacecraft and it's inhabitants. To mitigate this, I figure there might be two options:

1. Integrate many tiny warp drives into the spacecraft, and activate them all such that, when their fields interact with each other, the spacecraft is in a relatively undistorted field, but the net affect of the tiny warp cores would still warp space a good distance outside the craft.
2. To make a simpler craft, have just one warp drive, but design the craft to fit snugly in whatever undisturbed space exists near the drive.

And idea #2 is where the idea of a flying saucer looks pretty damned interesting. If a single warp drive had a limited area of weakly-disturbed space, say, a disk-like region circumventing the drive, why not build the spacecraft in there? This would make for a flying saucer whose engine is placed right in the center of the craft and oriented vertically, so that "up" is the direction of travel. In a gravity field, "up" would also be the direction the drive would need to be to counter gravity, so it works out kinda conveniently to where the bottom of the craft is always oriented downward when in a gravity field (hovering around in a planet's atmosphere). This makes for a spacecraft with a single warp drive doing everything, and whose construction is such that the ship's mass is just around the nicer regions of the warp drive's warp field. True, a saucer flying in the "up" direction in an atmosphere isn't exactly aerodynamic, but who knows, if it's warping through atmosphere, maybe aerodynamics are totally irrelevant?

Also, a flat ship would land nicely and not be knocked over so well by wind or whatever as opposed to a tall, rocket-like configuration.

I dunno, whadaya think?

**cosmictraveler** · 05-12-09, 10:41 AM

They do not need space ships, they travel using a similar device like the Stargate.

**Oli** · 05-12-09, 11:11 AM

Originally Posted by weed_eater_guy

A show on the History Channel (I think) was talking about conspiracy theories behind the Nazis

They worked on them.
Sack AS-1 and some Focke-Wulf types etc.

and then the U.S. Air Force secretly developing flying saucers

They did work on circular planform aircraft, as did the US Navy and AVro Canada.

apparently just for the damned sake of making an aircraft with a circular wing platform, which, as one about to graduate with an Aerospace Engineering degree, I can say is just about worthless for subsonic flight (aspect ratio is extremely low) and crap for supersonic flight

V-173, XF5U etc...?
http://www.amazon.com/Secret-Project.../dp/1857802330
Not "UFO-type" flying saucers but serious projects.
Well worth the read.
XF5U for one had a 10:1 max:min speed ratio - not bad for a piston-engined aircraft.

(a blunt leading edge would make a lot of drag and sonic boom at those speeds).

The bluntness of the leading edge is nothing to do with the planform, you could make a sharp LE regardless of that.
And surely T/C counts for more?

**weed_eater_guy** · 05-12-09, 02:45 PM

Well, you're right, the bluntness of the L.E. has nothing to do with the aspect ratio, any supersonic fighter wing is proof of that. However, a circular wing WILL have that blunt L.E., which sucks.

The XF5U would've had very bad performance were it not for the tactful use of propeller vorticity to counter the wingtip vorticity. But really, it's just a stumpy elliptical wing, and is very dependent on those engines for flight capability. The thought of dead-sticking that thing scares the crap outta me, lol.

The AVrocar, I think you're referring to, completely sucked from what I remember. Making what is essentially a saucer-shaped vehicle with a ducted fan rather then a helicopter rotor is a candidate VTOL method, but in itself is kinda crappy compared to a standalone helicopter. One could couple that with a forward drive system and a sealable fan duct to make a saucer-shaped aircraft that transforms back and forth between a conventional aircraft configuration and a hovering configuration, but it would probably not be very good at either task. Jump-jets and, maybe, the V-22 fill this roll a little safer with better performance.

The book looked interesting except, well... I can't believe some of the concepts on the front cover. They make no sense. Unlike the XF5U which used props to counter the wingtip vorticies, the jet-powered thingies just, look, well... dumb. Perhaps, juuuust maybe, they have a slight bit of merit as stealth vehicles, but I'm kinda skeptical.

I'll look into it some more later, but really, I'm just trying to do a practical look at how a warp drive spacecraft might work, and am wondering if a saucer shape might actually fit the bill.

**Fraggle Rocker** · 05-12-09, 03:23 PM

Originally Posted by weed_eater_guy

why the hell would anyone, let alone any alien species, make a saucer-shaped craft?

Because it's designed for space travel, not air travel. The unspoken presumption is that if these aliens are so far advanced that they can cross interstellar space (I think even the UFO enthusiasts have accepted the near certainty that these visitors can't possibly be from our solar system), then their technology is so far ahead of ours that they can travel through the air in a craft that is not aerodynamically efficient.

**Oli** · 05-12-09, 03:27 PM

Originally Posted by weed_eater_guy

Well, you're right, the bluntness of the L.E. has nothing to do with the aspect ratio, any supersonic fighter wing is proof of that. However, a circular wing WILL have that blunt L.E., which sucks.

Nah, you make a sharp edged LE on a circular planform.

The AVrocar, I think you're referring to, completely sucked from what I remember.

Nope WS 606 etc.
John Frost had some nifty ideas.

The book looked interesting except, well... I can't believe some of the concepts on the front cover. They make no sense. Unlike the XF5U which used props to counter the wingtip vorticies, the jet-powered thingies just, look, well... dumb. Perhaps, juuuust maybe, they have a slight bit of merit as stealth vehicles, but I'm kinda skeptical.

It's a genuine lok at actual projects and manufactured vehicles - it avoids the woo woo stuff altogether.

I'll look into it some more later, but really, I'm just trying to do a practical look at how a warp drive spacecraft might work, and am wondering if a saucer shape might actually fit the bill.

Alcubierre's warp drive has been pretty much kicked into touch, I gave a link to the objections somewhere in another thread.

**nietzschefan** · 05-12-09, 04:42 PM

Originally Posted by Oli

AVro Canada.

**Oli** · 05-12-09, 04:49 PM

Yup, Dief should'a been shot for cancelling Arrow.
That thing would probably only just be going out of service now if they'd ever gone ahead with it.

**nietzschefan** · 05-12-09, 04:56 PM

Na's we'd still be making them. The range was insane and perfect for Canadian Air Defence. Might have even sold a few to Europe.

**Oli** · 05-12-09, 07:05 PM

IIRC the RAF was considering them as an option in lieu of (or to supplement) TSR.2.
Greg Goebel's site is pretty good for Arrow info, including this proposal: