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Weapons of WarThe machinery of warfare. Sponsored by Aviation History magazine.
Handley Page Herakles airliner. There's a Benny Hill episode featuring Benny Hill as a captain of a Herakles. He and his crew get drunk in the cockpit during flight and they grope scantily clad stewardesses in miniskirts and go-go boots.
__________________ They make it a desert, and call it peace.
-Calgacus, leader of the Caledonians: Tacitus
I helped a friend with the plans for a model, unfortunately we could never get the balance worked out. Statically the balance was easy enough, but as soon as you moved the model the asymmetry caused a shift in the cg. The center of gravity is the first derivative of the moment of inertia. At rest it is all linear, as soon as you alter the velocity, either by speeding up or slowing down, the effect of squared functions appear.
This may be visualized by fastening a small weight to a yardstick, say at 6". Depending on how much weight, the center of gravity will move from 18" to nearer the weight location. Now if you hold the yardstick at the balance point and move it, you will find that the inertia posessed by the yardstick and weight is no longer at the static center of gravity. The side with the weight possesses more inertia and will "lag behind". With a pilot who can react to these changing forces with control surface or trim input it is controllable, however without a gyro, an rc model is a nightmare to control. Also the asymmetrical drag causes problems, the drag increasing at the fourth power of velocity.
With modern small rate gyros available, these problems could be solved, I believe, and it would be a spectacular model.
__________________
"He was a wise man who invented beer." Plato
Political correctness is the metaphysical premise that one can pick up a turd by the clean end.
The thing about actual scale models is that the aerodynamics don't translate well into the different scale and materials.
True scale models are very very difficult to fly.
I like The "goblin."I think two were produced. I saw one at wright-Patterson or DC, forget which.
Wierd concept. There is a film where one crashed his windshield on the hook during retrieval testing. He was lucky to get hooked up.
The Ascender doesn't look that odd IMO, Looks kinda like a boxier J7W Shinden, The Germans also had a similar design.
The XF5U-1 Flying Flapjack.
There are also the various Ekranoplan ground effect vehicles the Soviets developed during the cold war.
__________________ rm -Rf /bin laden
"Tell them that I don't know if we can release Don Slade alive by force. But I'll promise to burn their planet for his funeral pyre if we can't." -Colonel Alois Hammer Free Wargames!
What in the bloody blue blazes of hell does that thing do?????
Its a ekranoplan, IIRC the concept behind them was to allow for high-speed transport of personnel and cargo over smooth surfaces like the sea or polar ice caps while eluding radar.
I think the Russians had some major problems that lead to them abandoning new production due to a lack of good flight control/navigation systems and they wouldn't stay stable, Boeing is developing a heavy cargo carrier (Which could carry "17 M-1 main battle tanks in a single sortie") and apparently the Chinese are also messing around with the idea as well.
Sorta, They skim a few feet off the surface, Some of them (Like the A-90 Orlyonok below) are apparently able to get up to around 9,000 feet, Others probably didn't fly higher than 50ft like the M-160 Lun which was armed with 6 anti-shipping missiles.
__________________ rm -Rf /bin laden
"Tell them that I don't know if we can release Don Slade alive by force. But I'll promise to burn their planet for his funeral pyre if we can't." -Colonel Alois Hammer Free Wargames!
What in the bloody blue blazes of hell does that thing do?????
Can it fly?????
The idea is that these planes are really just "fast ships". They are kind of like a hydroplane where the idea is to get the hull out of the water to eliminate drag.
Using the "ground effect", the stubby wings produce lift by compressing the air between the wing and the water. This high pressure zone lifts the "ship/plane" out of the water and speeds of around 300 mph can be achieved.
Think about a nuke carrier zipping across the ocean at 300 mph! It could sail around the world in few days! I'm surprised we don't see more of this technology.
__________________ Battles are dangerous affairs... Wang Hsi ~2000 B.C.
While I agree with the conclusions and basic premise, as a physicist, I have to take issue with some of the details.
Quote:
Originally Posted by w john spurrell
Statically the balance was easy enough, but as soon as you moved the model the asymmetry caused a shift in the cg.
The cg does not change due to motion unless you are dealing with special relativity or the mass distribution changes due to the motion (e.g. fuel sloshing around in a tank).
Quote:
Originally Posted by w john spurrell
Also the asymmetrical drag causes problems, the drag increasing at the fourth power of velocity.
However, this still makes a non-linear effect and since the aircraft is asymetrical, the drag on either side of the plane can vary a LOT as the planes velocity changes. This will cause the plane to "yaw" (rotate around it's vertical axis) which in turn can cause asymetrical lift on the wings which will make the plane "roll" (rotate around the longitudinal axis).
This combination of yaw and roll would indeed be a real problem! As indicated, these effects don't scale linearly from model to actual plane so I can imagine the model can have serious flying issues compared to the "real" thing.
I would still like to have one though.
__________________ Battles are dangerous affairs... Wang Hsi ~2000 B.C.
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