June 28, 200619 yr What? No... We're 9th cousins, three times removed. Which means.. you're not related!
June 28, 200619 yr model airplanes arent scale though. Since they can create Extreme amounts of lift and be light as hell. The plane would have to be made of Depleated Urainum (sp) for it to be scale.
May 25, 200916 yr The question was: Will an airplane on a treadmill (i.e. stationary) with the engine running take off? The answer is yes. Mythbusters link
May 25, 200916 yr Haha, a lot of people got pwnt. Makes perfect sense, since the propeller is the one moving the plane and not the wheels.
May 26, 200916 yr Author Propeller? Since when was this a propeller driven plane??? I thought it was a jet!
May 26, 200916 yr Author OK, so wind isn't the right term. No flow of air around the airfoil (wing), no lift, no flight, no exceptions. This principle is still 100% sound, and THAT was the point.
May 26, 200916 yr Propeller? Since when was this a propeller driven plane??? I thought it was a jet! Well this is the first time I have ever heard of this myth, and the planes they tested were propeller driver. The same principle applies to turbofan, turbojet, turboprop, and so on engines if you want to be technical.
May 26, 200916 yr Author The question was: Will an airplane on a treadmill (i.e. stationary) with the engine running take off? The answer is yes. Mythbusters link That is a teaser video, the question is not answered, am I missing something? Once again, the propeller does NOT create lift, it moves the plane forward at high speed which moves air under & over the wings & that (& ONLY that) creates lift in a fixed wing airplane. (this obviously excluding the Harrier Jet, Helicopters etc.)
May 26, 200916 yr Youtube is your friend. The thrust produced by, in this case, the propeller, drives the plane forward and not the wheels. This allows the plane to continue to move and therefore build lift.
May 26, 200916 yr Author Youtube is your friend. The thust produced by, in this case, the propeller, drives the plane forward and not the wheels. This allows the plane to continue to move and therefore build lift. you need to REREAD the thread. I KNOW what does & does NOT drive a plane. I was up on the ins & outs of aviation by the age of 11/12.
May 26, 200916 yr Yes of course silly me, you know everything there is to know and I must not know anything.
May 26, 200916 yr Ok, if I recall correctly, the original question goes something like this: the conveyor will automatically increase in speed to instantly compensate for any forward motion of the airplane, right? If an airplane is sitting on a platform, engines off, no brakes activated, and you move the platform, does the airplane move with the platform? Yes, unless the platform moves out from under it suddenly. Why? Because of friction in the bearings of the wheels. If you remove all friction from the equation, the inertia of the airplane would mean that the wheels, which have no friction except between the rubber and the platform, would rotate, and the plane would not move in spite of the platform moving. If you then apply those same assumptions (there is friction between the tire & surface, there is no friction in the bearings), then the movement of the conveyor has no bearing whatsoever on the motion of the body of the airplane. Thus, if another force is applied to the body from the plane's engine, it doesn't matter what the conveyor does, the plane will move forward. In (almost) real life, there is friction in bearings. So, if we assume that the conveyor has no limit on its acceleration, then the instant that the plane begins to move, the conveyor would instantaneously increase in speed to an infinite amount trying to counteract the movement of the plane, until the bearings simply exploded and the plane fell on the ground. Conclusion: the answer to this puzzle depends completely on how the puzzle is worded, and the assumptions you make, but in general, the force introduced into the system by the conveyor does nothing but spin the wheels, it does not move the body, and the plane will still take off.
May 26, 200916 yr Author Sorry to come off as a dick, but I agree w/ Purdue: It's all in the wording. DF: I was put off by your "people got owned" comment when in this instance Mythbuuster's attempt to solve the riddle was lame & not at all sufficient to be considered a tie breaker. A sheet of canvas pulled by a pickup is NOT at all even close to the hypothetical conveyor belt the original question describes.
May 26, 200916 yr It was tested in reality, and it was debunked in reality. You're more than welcome to develop this hypothetical conveyor and prove everybody wrong, but I'm not going to hold my breath. While you're at it, you can also disprove Schrödinger's cat, since you're obviously brilliant when it comes to quantum mechanics.
May 26, 200916 yr Quantum mechanics are a dying breed, as most Quantums are in the junkyard by now. -- It's worth noting that, for those who require an actual conveyor belt, but like the rest of the world don't have the money, time, or care to do a full size 100% ZOMG conveyor belt, they did test it on a scale model (before they did the full scale test) with an "actual" conveyor belt and the results were the same.
June 10, 200916 yr Author In theory, we could be telleporting $h! by now. So says much of science. So why are we shipping goods on cargo ships & still flying on B-747s? Einstein's theory of relativity was the catalyst for the Atom bomb, and it also says time travel is possible. I'm still waiting. IF there is no movement of the plane as relative to the conveyor belt & ground, and therefore the air-speed remains at ZERO, the place can NOT fly. That's absolute fact. LIFT in a conventional aircraft "fixed wing" is not possible without a given airspeed.... Saying $h! like "the airflow/thrust of the propeller would allow lift in under the wings" is so dumb it makes my brain hurt. It's the aviation equivalent of the whole "you're in an elevator that is falling at terminal velocity so you jump just a split second before impact and survive without a scratch..." scenario. Edited June 10, 200916 yr by Sixty8panther
June 10, 200916 yr [quote name='Sixty8panther' date='Jun 9 2009, 10:03 PM' post='5IF there is no movement of the plane as relative to the conveyor belt & ground, and therefore the air-speed remains at ZERO, the place can NOT fly. There. Right there is where you miss the point. You are assuming the conveyor is able to keep the plane at a speed of zero relative to the ground. And that assumption is wrong. All the conveyor can do (friction aside because it's a hypothetical question) is make the free-spinning wheels spin faster. The speed at which the wheels spin has nothing to do with the speed of the airplane since the wheels do not propel the airplane.
June 10, 200916 yr [quote name='Sixty8panther' date='Jun 9 2009, 10:03 PM' post='5IF there is no movement of the plane as relative to the conveyor belt & ground, and therefore the air-speed remains at ZERO, the place can NOT fly. There. Right there is where you miss the point. You are assuming the conveyor is able to keep the plane at a speed of zero relative to the ground. And that assumption is wrong. All the conveyor can do (friction aside because it's a hypothetical question) is make the free-spinning wheels spin faster. The speed at which the wheels spin has nothing to do with the speed of the airplane since the wheels do not propel the airplane. This
June 10, 200916 yr In theory, we could be telleporting $h! by now. Also this: Scientist Teleport Matter More Than Three Feet
June 10, 200916 yr Author (friction aside because it's a hypothetical question) The friction is a factor YOU choose to ignore. That's conveniently selective. In YOUR opinion friction is hypothetical but yet the conveyor able to keep up with this known control is also hypothetical. Once again, I'm not saying I do not see both sides, but some people's wording is incorrect.
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