I would have thought the electric current needed to move a train would be pretty powerful, it would have to be AC and most likely triple phase.
I think it would kill you !
The questions-not-worth-their-own-thread question thread XII
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I would have thought the electric current needed to move a train would be pretty powerful, it would have to be AC and most likely triple phase.
I think it would kill you !
This is not easily possible as far as I can remember (although you can do it for scenario files quite easily, on the World Sizes tab of the rules in the editor), but you might be able to get a complicated answer at the Civ3 C&C section, as ganglieri pointed out.
I thought you'd recommend rubbing 2 sticks together. I am disappointed
I thought we were all into 'save the rainforest' nowadays?
A few nights ago at the pub, after a couple of gallons of beer or in my case coke (still not drinking, and proud) one of 'the guys' asked whether, with all these defence cuts, it wouldn't be a great idea to turn the flight deck of an aircraft carrier into a giant treadmill, on the grounds that you could fit far more aircraft because they could take off on the spot (OK, they'd still need some room in the front to avoid hitting the next one as they rose). Another mate said that it was a stupid idea, since they can't take off unless they're actually moving forward. I sat back, sipped my coke, and watched the fireworks. Unfortunately, no answer was forthcoming so I'm putting the question here.
Suppose an aircraft is put onto a treadmill, as long and as wide as a runway, which is somehow programmed to exactly match the speed of the aircraft's wheels. Can the aircraft, assuming as much engine power as you like, take off?
First correct answer wins a smug smile and a mention from me next time we end up in the same place.
The who? So you reckon that this flow of air, which is parallel to the ground, can make the aircraft take off? Not quite sure how that works to be honest. I know Bernoulli's law about how air flow over the wings creates lift, but that would require the plane to be moving relative to the air, wouldn't it?
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It's the air flow created by the engines that produces lift. Also, the Mythbusters pretty much answered that question already.
ParadigmShifter
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No, it wouldn't take off. This was asked at gamedev.net forums and that was the answer 
Er... a search there for 'aircraft treadmill' came up with one result about governmental bailouts, one about Obama, and what looks like a gigantic listing of words headed 'help'.
ParadigmShifter
Random Nonsense Generator
Yeah I couldn't find it searching on gamedev either. It was a while back.
Searching google with "plane + conveyor" gave lots of hits but no definite answer
Searching google with "plane + conveyor" gave lots of hits but no definite answer
A Harrier could. So could a helicopter. Or other VSTOL aircraft. For the rest, I can't quite picture the mechanics of your treadmill from the description.
ParadigmShifter
Random Nonsense Generator
http://www.straightdope.com/columns...the-opposite-direction-can-the-plane-take-off
This seems to be the correct answer.
The plane does take off because the wheels aren't powered, so the plane WILL move forward, just the wheels will spin twice as fast. No matter how fast the conveyor belt is, the plane will move forward.
This seems to be the correct answer.
The plane does take off because the wheels aren't powered, so the plane WILL move forward, just the wheels will spin twice as fast. No matter how fast the conveyor belt is, the plane will move forward.
A harrier can't carry out a vertical takeoff or landing if it's loaded with enough armament to mean anything. I think the yanks built an aircraft with a helicopter rotor and a aeroplane's wing, but I don't know what happened to it or if it ever saw service.
PS: thanks for that. I actually think I understand it as well.
aimeeandbeatles
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I read somewhere that someone once built a plane that could take off and land vertically. However they kept crashing them when they tried to land.
ParadigmShifter
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Harrier jump jets can do that. That's what VTOL stands for (vertical take-off and landing).
I always wondered what VTOL stands for - it's one of the best units in Civ II: Test of Time!
V-22 Osprey. It is seeing service, even in combat operations.
The correct answer is that this as seen on the Internet or Mythbusters or whatever was literally mistranslated from some original problem in Russian iirc, to which the answer was clear.
The point of the argument wasn't to assume a treadmill, it was to assume that the plane had to stay still relative to the ground horizontally- ie. if you had a massive chain or something tied to the back to hold in place horizontally, that would be the same.
In that case, the answer is a regular plane will not create enough lift with it's engines - the engines won't just "suck in enough air" - that's the distinction between VTOL or something like a helicopter versus a regular jet.
But anyway, it's been answered and whatever real-world scenario you're thinking of, the physics can be examined and makes sense.
The Harriers that I know are VSTOL, which is Vertical/Short Take Off and Landing which has some fancy definition equating to 'you can use a really short runway, but not a helipad'. This is because, as you said, it can go pretty much straight up unloaded, but by the time it has missiles and all the other implements of perferating one's fellow man it's too heavy and can only be categorised as STOL.
Well the mechanics question I had was cleared up with PS's link showing that the aircraft wheels would have to be moving twice as fast as the treadmill. Not the same speed. If they were rolling the same speed, then the aircraft would have no forward motion, and therefor no lift. But because of the propulsion systems of aircraft, the whole thing is silly, as the wheels don't provide motion, only allow it.
Were you thinking of this thing?
Or this?
The top one. I wasn't aware that it had ever been used, I thought they'd found something fundamentally wrong with the concept; but obviously not.
Well, that's a matter of some debate 
Early in production they weren't very safe. And even now, after they've been in service for a while, they really don't seem to be living up to expectations. They were intended to be a double or triple speed heavy transport helicopter.
Seems pretty typical of modern US military procurement boondoggles.
Early in production they weren't very safe. And even now, after they've been in service for a while, they really don't seem to be living up to expectations. They were intended to be a double or triple speed heavy transport helicopter.
http://en.wikipedia.org/wiki/Bell-Boeing_V-22_Osprey#Controversy
Seems pretty typical of modern US military procurement boondoggles.
Don't get me started on British ones. Disregarding the Enfield No.2 (whose story I won't tell unless anyone actually wants to hear it), we're the country that invented the plug-in bayonet. And while you yanks have the money to sort out and cover up your mistakes, we don't really.
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