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"Simple answer is no. If the plane is technically not moving there is no air flow around the wings so no lift is generated. Simple theory of flight." I have passed exams on this stuff. Just to clarify.. | |||
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"Simple answer is no. If the plane is technically not moving there is no air flow around the wings so no lift is generated. Simple theory of flight." Airflow is generated by prop not the frames relationship to the ground | |||
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"Yes. And I cannot believe this is still running. The Mythbusters link was posted at least 3 times. Did nobody watch it?" Yep. Sort of ended the debate I thought lol. Jack | |||
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"No it can't, engines surely provide forward momentum not lift, the forward motion does not provide "lift" in the normal sense, on the wing it provides negative air pressure on the top side of the wing and positive air pressure under, this effect gives the lift. No movement = no lift.. S That's what I believed anyway. S " But there will be movement. The wheels rotate freely, whatever they do won't stop the aircraft from moving. It will be propelled forwards as normal. | |||
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"No it can't, engines surely provide forward momentum not lift, the forward motion does not provide "lift" in the normal sense, on the wing it provides negative air pressure on the top side of the wing and positive air pressure under, this effect gives the lift. No movement = no lift.. S That's what I believed anyway. S But there will be movement. The wheels rotate freely, whatever they do won't stop the aircraft from moving. It will be propelled forwards as normal." But there is no relative forward motion to the air around the plane, it is this relative movement that provides the lift.. S | |||
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"No it can't, engines surely provide forward momentum not lift, the forward motion does not provide "lift" in the normal sense, on the wing it provides negative air pressure on the top side of the wing and positive air pressure under, this effect gives the lift. No movement = no lift.. S That's what I believed anyway. S But there will be movement. The wheels rotate freely, whatever they do won't stop the aircraft from moving. It will be propelled forwards as normal. But there is no relative forward motion to the air around the plane, it is this relative movement that provides the lift.. S" There will be forward motion. The belt will not stop the 'plane moving forward. The movement of the wheels will be affected by the belt. The wheels don't control the movement of the 'plane though. They don't connect to any part of any drive system. Fogetting the belt completely for the moment, if the wheels didn't rotate but were fixed and the engines were started and accelerated as normal, what do you think would happen? | |||
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"So you are saying a plane that to all intents and purposes has no relative forward movement on a conveyor belt that will turn at the same speed as the wheels, could be sitting in front of me and in effect take of vertically, because that's what it would be doing? Really? S" It will move forwards normally. It will have forward motion. Aircraft are not driven by their wheels. | |||
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"No it can't, engines surely provide forward momentum not lift, the forward motion does not provide "lift" in the normal sense, on the wing it provides negative air pressure on the top side of the wing and positive air pressure under, this effect gives the lift. No movement = no lift.. S That's what I believed anyway. S But there will be movement. The wheels rotate freely, whatever they do won't stop the aircraft from moving. It will be propelled forwards as normal. But there is no relative forward motion to the air around the plane, it is this relative movement that provides the lift.. S There will be forward motion. The belt will not stop the 'plane moving forward. The movement of the wheels will be affected by the belt. The wheels don't control the movement of the 'plane though. They don't connect to any part of any drive system. Fogetting the belt completely for the moment, if the wheels didn't rotate but were fixed and the engines were started and accelerated as normal, what do you think would happen?" The plane would destroy itself or at least the engines or wheels/tyres because its trying to move? But the conveyor is matched perfectly to the "supposed" forward movement, but the plane does not move relative to the air around it, it you were standing next to it the plane would not be moving, the wheels & engines might be saying "I'm doing take off speed guys" but the wings waiting for their airflow to provide lift will be saying "fuck off are you".. S | |||
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"No it can't, engines surely provide forward momentum not lift, the forward motion does not provide "lift" in the normal sense, on the wing it provides negative air pressure on the top side of the wing and positive air pressure under, this effect gives the lift. No movement = no lift.. S That's what I believed anyway. S But there will be movement. The wheels rotate freely, whatever they do won't stop the aircraft from moving. It will be propelled forwards as normal. But there is no relative forward motion to the air around the plane, it is this relative movement that provides the lift.. S There will be forward motion. The belt will not stop the 'plane moving forward. The movement of the wheels will be affected by the belt. The wheels don't control the movement of the 'plane though. They don't connect to any part of any drive system. Fogetting the belt completely for the moment, if the wheels didn't rotate but were fixed and the engines were started and accelerated as normal, what do you think would happen? The plane would destroy itself or at least the engines or wheels/tyres because its trying to move? But the conveyor is matched perfectly to the "supposed" forward movement, but the plane does not move relative to the air around it, it you were standing next to it the plane would not be moving, the wheels & engines might be saying "I'm doing take off speed guys" but the wings waiting for their airflow to provide lift will be saying "fuck off are you".. S" Ok, you're missing my point. Go and watch the Mythbusters video. (Or read The Goddamn Airplane on the Goddamn Treadmill on XKCD which explains why this is actually a completely bullshit question) | |||
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"No it can't, engines surely provide forward momentum not lift, the forward motion does not provide "lift" in the normal sense, on the wing it provides negative air pressure on the top side of the wing and positive air pressure under, this effect gives the lift. No movement = no lift.. S That's what I believed anyway. S But there will be movement. The wheels rotate freely, whatever they do won't stop the aircraft from moving. It will be propelled forwards as normal. But there is no relative forward motion to the air around the plane, it is this relative movement that provides the lift.. S There will be forward motion. The belt will not stop the 'plane moving forward. The movement of the wheels will be affected by the belt. The wheels don't control the movement of the 'plane though. They don't connect to any part of any drive system. Fogetting the belt completely for the moment, if the wheels didn't rotate but were fixed and the engines were started and accelerated as normal, what do you think would happen? The plane would destroy itself or at least the engines or wheels/tyres because its trying to move? But the conveyor is matched perfectly to the "supposed" forward movement, but the plane does not move relative to the air around it, it you were standing next to it the plane would not be moving, the wheels & engines might be saying "I'm doing take off speed guys" but the wings waiting for their airflow to provide lift will be saying "fuck off are you".. S Ok, you're missing my point. Go and watch the Mythbusters video. (Or read The Goddamn Airplane on the Goddamn Treadmill on XKCD which explains why this is actually a completely bullshit question)" OK, I'll do it in the morning S | |||
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"No it can't, engines surely provide forward momentum not lift, the forward motion does not provide "lift" in the normal sense, on the wing it provides negative air pressure on the top side of the wing and positive air pressure under, this effect gives the lift. No movement = no lift.. S That's what I believed anyway. S But there will be movement. The wheels rotate freely, whatever they do won't stop the aircraft from moving. It will be propelled forwards as normal. But there is no relative forward motion to the air around the plane, it is this relative movement that provides the lift.. S There will be forward motion. The belt will not stop the 'plane moving forward. The movement of the wheels will be affected by the belt. The wheels don't control the movement of the 'plane though. They don't connect to any part of any drive system. Fogetting the belt completely for the moment, if the wheels didn't rotate but were fixed and the engines were started and accelerated as normal, what do you think would happen? The plane would destroy itself or at least the engines or wheels/tyres because its trying to move? But the conveyor is matched perfectly to the "supposed" forward movement, but the plane does not move relative to the air around it, it you were standing next to it the plane would not be moving, the wheels & engines might be saying "I'm doing take off speed guys" but the wings waiting for their airflow to provide lift will be saying "fuck off are you".. S" Sigh, you're mistaking groundspeed for true airspeed. This has become so fucking tiresome now. | |||
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"No it can't, engines surely provide forward momentum not lift, the forward motion does not provide "lift" in the normal sense, on the wing it provides negative air pressure on the top side of the wing and positive air pressure under, this effect gives the lift. No movement = no lift.. S That's what I believed anyway. S But there will be movement. The wheels rotate freely, whatever they do won't stop the aircraft from moving. It will be propelled forwards as normal. But there is no relative forward motion to the air around the plane, it is this relative movement that provides the lift.. S There will be forward motion. The belt will not stop the 'plane moving forward. The movement of the wheels will be affected by the belt. The wheels don't control the movement of the 'plane though. They don't connect to any part of any drive system. Fogetting the belt completely for the moment, if the wheels didn't rotate but were fixed and the engines were started and accelerated as normal, what do you think would happen? The plane would destroy itself or at least the engines or wheels/tyres because its trying to move? But the conveyor is matched perfectly to the "supposed" forward movement, but the plane does not move relative to the air around it, it you were standing next to it the plane would not be moving, the wheels & engines might be saying "I'm doing take off speed guys" but the wings waiting for their airflow to provide lift will be saying "fuck off are you".. S Ok, you're missing my point. Go and watch the Mythbusters video. (Or read The Goddamn Airplane on the Goddamn Treadmill on XKCD which explains why this is actually a completely bullshit question) OK, I'll do it in the morning S" The XKCD one is worth a read. It has pictures and stuff. It explains there are three different ways to look at it, which is why opinions tend to be polarised, with each side patiently trying to explain physics to the other . Oh, and one of those ways is actually physically impossible, just to make matters clearer! This question has been banned there for ages due to near outbreak of war over it! | |||
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"Fuck me this should be down in the politics section! Two sides arguing and not listening to each other and both think they're right " Great ain't it? | |||
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"The aircraft on the conveyor stays put! " No. It does not stay still. grab a toy car, hold it by the roof in your right hand and run your left hand under neath it, what happens? right the car is held in place and the wheels spin... Now while running your left hand under the wheels backwards push the car forwards with your right hand. What happened? the car moved forwards despite your left hand moving backwards, But the wheels span faster while the car moved forwards. But it still moved forwards... just as the plane would, spinning the wheels faster made no difference to the speed your right hand moved the car. The only way a conveyor could make any difference is if the airplane was powered by its wheels. If it was it would be a bus! | |||
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"Pisser, is this one still running Nobody googled conveyor vs plane to see the mythbusters clip? It's only been mentioned about 10 times across the threads " Pmsl I think this one will go on and on xx | |||
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"The thing is, that once the engines kicked in, the conveyor would have no effect other than spinning the wheels much quicker. the plane would still move forward relative to the air around it and the conveyor would be unable to keep the plane in the same spot. So... the plane would respond in exactly the same way as it would on a proper runway. With this in mind, the conveyor is actually a massive waste of energy and probably the reason that air-fares are soo expensive. Cal" I was laying in bed last night thinking about this (sad I know) and was thinking along the lines of the toy car analogy above but with me on roller skates Anyway, having lost sleep over this I also have to concede I was wrong last night Why is Cal always right? Nits | |||
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"Simple answer is no. If the plane is technically not moving there is no air flow around the wings so no lift is generated. Simple theory of flight. I have passed exams on this stuff. Just to clarify.." I didn't, I watched mythbusters | |||
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"Has no one on here ever heard of V.T.O.L Planes. They are vertical take off lif jets. They have been in use for over 40 years by both the USA and UK. More commonly known as Jump jets. Most common one being the Harrier Jump jet." You forgot to add "and has nothing to do with this problem" | |||
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"Simple answer is no. If the plane is technically not moving there is no air flow around the wings so no lift is generated. Simple theory of flight. Airflow is generated by prop not the frames relationship to the ground" No. Airflow over the wings is from forward motion. As it's on a roller there is no effective forward motion. Engines provide thrust (negated in this case by rolling road) wings provide lift. The two are separate. | |||
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"Simple answer is no. If the plane is technically not moving there is no air flow around the wings so no lift is generated. Simple theory of flight. Airflow is generated by prop not the frames relationship to the ground No. Airflow over the wings is from forward motion. As it's on a roller there is no effective forward motion. Engines provide thrust (negated in this case by rolling road) wings provide lift. The two are separate. " Nobody is saying a stationary aircraft can fly! The plane will move forwards, the treadmill has no effect on the plane apart from making its wheels spin. Read my post a bit above and see what you think. | |||
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" Fucking hell this is still going pmsl Saying nowt " Maybe , 'oops, I see what you mean, it will move forwards and fly?' | |||
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"Of course the belt impacts the flight of the plane. Take away the belt for the moment. Engines fire up and push the plane along...on its wheels. If the wheels have a 1m circumference then for every rotatio of the wheel the plane moves forward 1meter. Plane moves forward fast enough the shape of the wings means that the air travelling over the top has further to travel than tbe air passing under the wing in the same time producing lift. Reintroduce the belt. Engines fire up, wheels rotate once...plane hasn't moved forward 1meter because the ground (the belt) moved backwards one meter...plane not moving forward = no air travling over the wings so no lift" how much the wheels turn is irrelevant, they are just free spinning, not like car drive wheels. Think if you were at the gym on a flat treadmill wearing a pair of roller skates standing motionless. You switch the treadmill on, you could hold yourself stationary with a piece of cotton. It wouldn't matter if the belt was going 100mph forwards or back, you would stay still. The plane is the same. The belt just spins the aircraft wheels, not move it back. | |||
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"Of course the belt impacts the flight of the plane. Take away the belt for the moment. Engines fire up and push the plane along...on its wheels. If the wheels have a 1m circumference then for every rotatio of the wheel the plane moves forward 1meter. Plane moves forward fast enough the shape of the wings means that the air travelling over the top has further to travel than tbe air passing under the wing in the same time producing lift. Reintroduce the belt. Engines fire up, wheels rotate once...plane hasn't moved forward 1meter because the ground (the belt) moved backwards one meter...plane not moving forward = no air travling over the wings so no lift" Really trying to get my head around this argument... It sounds as if you think that the engines drive the plane along by turning the wheels - like in a car... Is that right...? Um - er.... wot...? OK, just take the wheels off, and fit skids instead... now explain it to me again please.... | |||
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"Of course the belt impacts the flight of the plane. Take away the belt for the moment. Engines fire up and push the plane along...on its wheels. If the wheels have a 1m circumference then for every rotatio of the wheel the plane moves forward 1meter. Plane moves forward fast enough the shape of the wings means that the air travelling over the top has further to travel than tbe air passing under the wing in the same time producing lift. Reintroduce the belt. Engines fire up, wheels rotate once...plane hasn't moved forward 1meter because the ground (the belt) moved backwards one meter...plane not moving forward = no air travling over the wings so no lift" Tell me you are trolling and this is not your thought process , please tell me this ? The distance traveled is relative to the air when propelled by a fucking jet engine , the number of wheel rotations is totally irrelevant. In your example the wheels would rotate once to match the belt speed and then again to match the forward through air speed | |||
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"The plane has to travel along the ground until lift is greater than its weight. So, no the engines dont directly drive the wheels, they push the plane....along the ground...if the ground is moving backwards at the same rate as the plane is being pushed forwards (either on wheels or skids) the plane isn't moving" They push the plane forward , the ground has no relation to this other than upward support | |||
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"Of course the belt impacts the flight of the plane. Take away the belt for the moment. Engines fire up and push the plane along...on its wheels. If the wheels have a 1m circumference then for every rotatio of the wheel the plane moves forward 1meter. Plane moves forward fast enough the shape of the wings means that the air travelling over the top has further to travel than tbe air passing under the wing in the same time producing lift. Reintroduce the belt. Engines fire up, wheels rotate once...plane hasn't moved forward 1meter because the ground (the belt) moved backwards one meter...plane not moving forward = no air travling over the wings so no lift how much the wheels turn is irrelevant, they are just free spinning, not like car drive wheels. Think if you were at the gym on a flat treadmill wearing a pair of roller skates standing motionless. You switch the treadmill on, you could hold yourself stationary with a piece of cotton. It wouldn't matter if the belt was going 100mph forwards or back, you would stay still. The plane is the same. The belt just spins the aircraft wheels, not move it back." But to move forward the wheels would need to move faster than the belt. The origional post states that as the speed of the wheels increases so does the speed of the belt (the distinguishing factor between the given question and the mythbusters test). This means that the plane wont move forwards and so can't generate lift | |||
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"The plane has to travel along the ground until lift is greater than its weight. So, no the engines dont directly drive the wheels, they push the plane....along the ground...if the ground is moving backwards at the same rate as the plane is being pushed forwards (either on wheels or skids) the plane isn't moving They push the plane forward , the ground has no relation to this other than upward support " Forward is relative to the ground? As in a distance....unless we are talking geostationary orbit...which we aren't. I challange anyone to move forward whilst staying on the same piece of ground | |||
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"Lincs white van man, please read what i've written about standing on a treadmill on roller skates. That is the crux of why it makes no difference." I have, and in that situation you are right, you remain stationary. The issue is to create lift the plane has to move forwards, not remain stationary | |||
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"Simple answer is no. If the plane is technically not moving there is no air flow around the wings so no lift is generated. Simple theory of flight. I have passed exams on this stuff. Just to clarify.." So how come you're so wrong? Ex aircraft engineer here. It'll take off. Engines give it thrust to take off. How fast the wheels freewheel is nothing to do with it. Simple. | |||
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"Of course the belt impacts the flight of the plane. Take away the belt for the moment. Engines fire up and push the plane along...on its wheels. If the wheels have a 1m circumference then for every rotatio of the wheel the plane moves forward 1meter. Plane moves forward fast enough the shape of the wings means that the air travelling over the top has further to travel than tbe air passing under the wing in the same time producing lift. Reintroduce the belt. Engines fire up, wheels rotate once...plane hasn't moved forward 1meter because the ground (the belt) moved backwards one meter...plane not moving forward = no air travling over the wings so no lift Tell me you are trolling and this is not your thought process , please tell me this ? The distance traveled is relative to the air when propelled by a fucking jet engine , the number of wheel rotations is totally irrelevant. In your example the wheels would rotate once to match the belt speed and then again to match the forward through air speed " Only once the plane is airborne...untill then it travels along the ground...on its wheels. If the plane was travelling along the ground faster than its wheels rotate theyd leave dirty great marks on the runway and blow out | |||
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"Of course the belt impacts the flight of the plane. Take away the belt for the moment. Engines fire up and push the plane along...on its wheels. If the wheels have a 1m circumference then for every rotatio of the wheel the plane moves forward 1meter. Plane moves forward fast enough the shape of the wings means that the air travelling over the top has further to travel than tbe air passing under the wing in the same time producing lift. Reintroduce the belt. Engines fire up, wheels rotate once...plane hasn't moved forward 1meter because the ground (the belt) moved backwards one meter...plane not moving forward = no air travling over the wings so no lift how much the wheels turn is irrelevant, they are just free spinning, not like car drive wheels. Think if you were at the gym on a flat treadmill wearing a pair of roller skates standing motionless. You switch the treadmill on, you could hold yourself stationary with a piece of cotton. It wouldn't matter if the belt was going 100mph forwards or back, you would stay still. The plane is the same. The belt just spins the aircraft wheels, not move it back. But to move forward the wheels would need to move faster than the belt. The origional post states that as the speed of the wheels increases so does the speed of the belt (the distinguishing factor between the given question and the mythbusters test). This means that the plane wont move forwards and so can't generate lift " Actually is says the belt matches the planes speed. The planes speed is not measured relative to belt but relative to the non moving ground or even the air . Thus as the huge jet engine pushes the plane forward through space the belt would travel at same speed backwards but this motion has no effect upon the plane as the plane is not tethered to the belt Only a big chain with a strength more than the thrust would keep the plane from moving forward I sense trolling ! | |||
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"Lincs white van man, please read what i've written about standing on a treadmill on roller skates. That is the crux of why it makes no difference. I have, and in that situation you are right, you remain stationary. Ok then just give the man a slight push he will move forward on the treadmill The issue is to create lift the plane has to move forwards, not remain stationary" | |||
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"Lincs white van man, please read what i've written about standing on a treadmill on roller skates. That is the crux of why it makes no difference. I have, and in that situation you are right, you remain stationary. The issue is to create lift the plane has to move forwards, not remain stationary" OK good. So lets step through: I can stay stationary on a treadmill, using no force. The aircraft on the giant treadmill would also stay stationary ,using no force. When its engines applied forward force to the air, it would move forward as normal. The treadmill has no method of applying any rearward force to the aircraft. | |||
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"Lincs white van man, please read what i've written about standing on a treadmill on roller skates. That is the crux of why it makes no difference. I have, and in that situation you are right, you remain stationary. The issue is to create lift the plane has to move forwards, not remain stationary OK good. So lets step through: I can stay stationary on a treadmill, using no force. The aircraft on the giant treadmill would also stay stationary ,using no force. When its engines applied forward force to the air, it would move forward as normal. The treadmill has no method of applying any rearward force to the aircraft." To move forward, how does the plane travel along the ground? On its wheels? | |||
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"The wheels are a red herring. There’s no need to get involved in explanations of “gravity”. So lets get rid of them. Replace the aircraft’s wheels with floats. Replace the conveyer belt with a very long straight channel of water – a canal. At one end is a massive dam, which can be used to make the canal water move at any speed through the canal. The float plane floats on the canal facing the dam If the water carries the float plane backwards through the air at the same speed as its engines are driving it forwards through the air, the wings can experience no air flow and can not lift the aircraft up. An observer will see the aircraft stationary. If the water is moving the aircraft backwards through the air at take-off speed, and the engines are driving it forward through the air at the same, the aircraft can not take off, and appears to be stationery to an observer. Stop the water flow, and zoom. Away she goes. Virtually instant take-off – VTOL! " not VTOL | |||
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" The treadmill has no method of applying any rearward force to the aircraft. To move forward, how does the plane travel along the ground? On its wheels?" Yes, an aircraft wheels just free turn, allowing the aircraft do what it wants. The belt has no way to push the aircraft back. | |||
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"No....take off depends on lift overcoming the gross mass of the aircraft. Lift is generated by airflow over the wings reaching a critical speed depending on the mass of the aircraft. As the conveyer belt does not speed up the airflow over the wings the aircraft will not take off...." Nobodys saying that. We are saying the aircraft just goes forward as normal as if it was on tarmac. the treadmill belt moving below has no influence on anything at all. | |||
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"Clearly not. Planes can only take off when the uplift provided by the wings is greater than the weight of the plane. The uplift is provided by air moving over the wings. Since the plane is stationary relative to the air around it...there is zero uplift. It's going nowhere!" So explain how you think that the plane is stationary...... | |||
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"Clearly not. Planes can only take off when the uplift provided by the wings is greater than the weight of the plane. The uplift is provided by air moving over the wings. Since the plane is stationary relative to the air around it...there is zero uplift. It's going nowhere!" On about VTOL...a Harrier for example does not need any airflow over its wings to take of vertically...Only needs those for moving forward. Shall we talk about vectored thrust now | |||
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"Ok so until take off it travels on its wheels. On you analogy, to move forwards on the running machine your rollerskate wheels need to be moving forwards faster than the tredmill is turning backwards? The origional question says the experiment is set up so the speed of tbe treadmill matches the speed of your rollerskate wheels. How can you move forwards?" It doesn't. Same as a jogger on a treadmill. | |||
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"Ok so until take off it travels on its wheels. On you analogy, to move forwards on the running machine your rollerskate wheels need to be moving forwards faster than the tredmill is turning backwards? The origional question says the experiment is set up so the speed of tbe treadmill matches the speed of your rollerskate wheels. How can you move forwards?" OK you keep repeating the same none truth What effect do you think the jet engines have upon the plane and how exactly does the movment of the treadmill affect this The wheels only support the plane the have zero influence upon the forward or backward motion | |||
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"Right, lets forget the plane for a minute. Back to the gym. Stand on the treadmill wearing roller skates. There is a rope tied to the wall in front of you. You hold the rope gently. you switch the treadmill on. You stay motionless. You speed the treadmill up. You stay motionless. You speed the treadmill up to 200mph. You stay motionless. You pull on the rope gently. you move forwards, same as on the floor. You are the plane. roller skates are its wheels. engines are the rope." You are wasting your time; They ; A. can't understand the question. B. don't know how a plane works, especially how it takes off, and can't get it out of their heads that the wheels do nothing except support the plane and provide minimal rolling resistance while it's taking off. C. Or that the " conveyor belt" is irrelevant | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?”" No this is the question And in this above question it even gives the answer "The plane moves " It says nothing about holding the plane still , that has been wrongly assumed and repeated In fact the wheels on the plane would be rotating at double the planes forward speed through space | |||
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"Please keep this going to part 3, it's turned into comedy gold. " Oh I hope so..... or it will be banned before it gets there!! | |||
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"Ok so until take off it travels on its wheels. On you analogy, to move forwards on the running machine your rollerskate wheels need to be moving forwards faster than the tredmill is turning backwards? The origional question says the experiment is set up so the speed of tbe treadmill matches the speed of your rollerskate wheels. How can you move forwards? OK you keep repeating the same none truth What effect do you think the jet engines have upon the plane and how exactly does the movment of the treadmill affect this The wheels only support the plane the have zero influence upon the forward or backward motion " as they are carrying or supporting the plane they need to move forwards for the plane to move forwards. Wheels do this by rolling...if they are rolling forwards at the same rate as the ground is moving bacwards they arent moving....so the plane isnt moving. If you are on rollerskates and i push you its my push that is the force moving you forwards. The rollerskates are only supporting you...but I'm pretty sure that the speed and distance you travel will be directly related to the rotations of the wheels | |||
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"Do I get cashew nuts or olives with my champagne up here in First Class?? Oh and when do we arrive at our destination? " Never, at the rate of some | |||
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"Ok so until take off it travels on its wheels. On you analogy, to move forwards on the running machine your rollerskate wheels need to be moving forwards faster than the tredmill is turning backwards? The origional question says the experiment is set up so the speed of tbe treadmill matches the speed of your rollerskate wheels. How can you move forwards? OK you keep repeating the same none truth What effect do you think the jet engines have upon the plane and how exactly does the movment of the treadmill affect this The wheels only support the plane the have zero influence upon the forward or backward motion as they are carrying or supporting the plane they need to move forwards for the plane to move forwards. Wheels do this by rolling...if they are rolling forwards at the same rate as the ground is moving bacwards they arent moving....so the plane isnt moving. If you are on rollerskates and i push you its my push that is the force moving you forwards. The rollerskates are only supporting you...but I'm pretty sure that the speed and distance you travel will be directly related to the rotations of the wheels " You are just trolling now | |||
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"Ok so until take off it travels on its wheels. On you analogy, to move forwards on the running machine your rollerskate wheels need to be moving forwards faster than the tredmill is turning backwards? The origional question says the experiment is set up so the speed of tbe treadmill matches the speed of your rollerskate wheels. How can you move forwards? OK you keep repeating the same none truth What effect do you think the jet engines have upon the plane and how exactly does the movment of the treadmill affect this The wheels only support the plane the have zero influence upon the forward or backward motion as they are carrying or supporting the plane they need to move forwards for the plane to move forwards. Wheels do this by rolling...if they are rolling forwards at the same rate as the ground is moving bacwards they arent moving....so the plane isnt moving. If you are on rollerskates and i push you its my push that is the force moving you forwards. The rollerskates are only supporting you...but I'm pretty sure that the speed and distance you travel will be directly related to the rotations of the wheels You are just trolling now " Is that translated as "i finally see your point?" If not then I suggest that there may well ba a troll. I'm still open to reasoned discussion...and if that discussion has me see that I'm wrong then i will comment as such, not call that person a troll... | |||
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"Ok so until take off it travels on its wheels. On you analogy, to move forwards on the running machine your rollerskate wheels need to be moving forwards faster than the tredmill is turning backwards? The origional question says the experiment is set up so the speed of tbe treadmill matches the speed of your rollerskate wheels. How can you move forwards? OK you keep repeating the same none truth What effect do you think the jet engines have upon the plane and how exactly does the movment of the treadmill affect this The wheels only support the plane the have zero influence upon the forward or backward motion as they are carrying or supporting the plane they need to move forwards for the plane to move forwards. Wheels do this by rolling...if they are rolling forwards at the same rate as the ground is moving bacwards they arent moving....so the plane isnt moving. If you are on rollerskates and i push you its my push that is the force moving you forwards. The rollerskates are only supporting you...but I'm pretty sure that the speed and distance you travel will be directly related to the rotations of the wheels You are just trolling now Is that translated as "i finally see your point?" If not then I suggest that there may well ba a troll. I'm still open to reasoned discussion...and if that discussion has me see that I'm wrong then i will comment as such, not call that person a troll..." Well for a start you still are not reading the question ( FUCKING big clue posted just now by the OP). It didn't say " wheels", it said "the plane." Anyway, its irrelevant. | |||
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"Ok so until take off it travels on its wheels. On you analogy, to move forwards on the running machine your rollerskate wheels need to be moving forwards faster than the tredmill is turning backwards? The origional question says the experiment is set up so the speed of tbe treadmill matches the speed of your rollerskate wheels. How can you move forwards? OK you keep repeating the same none truth What effect do you think the jet engines have upon the plane and how exactly does the movment of the treadmill affect this The wheels only support the plane the have zero influence upon the forward or backward motion as they are carrying or supporting the plane they need to move forwards for the plane to move forwards. Wheels do this by rolling...if they are rolling forwards at the same rate as the ground is moving bacwards they arent moving....so the plane isnt moving. If you are on rollerskates and i push you its my push that is the force moving you forwards. The rollerskates are only supporting you...but I'm pretty sure that the speed and distance you travel will be directly related to the rotations of the wheels You are just trolling now Is that translated as "i finally see your point?" If not then I suggest that there may well ba a troll. I'm still open to reasoned discussion...and if that discussion has me see that I'm wrong then i will comment as such, not call that person a troll..." That's the point reasoned discussion has been exceeded. The explanation cannot be made more clear . There is a word called obtuse, arguing not because one has a point but just to wind up You know full well free wheeling wheels have no relevance in this case and exceptionally clear explanations why not have been eloquently explained from a number of people in a variety of ways , deliberately missing the point for argument is trolling. Xx | |||
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"So the speed of the belt is set to match the speed of the plane, not the speed of its wheels?" Yes | |||
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"So the speed of the belt is set to match the speed of the plane, not the speed of its wheels?" It makes no difference either way. I don't want this to sound snotty, I just want to try to explain why it moves. Do you know the wheels aren't driving the plane during takeoff and taxiing? If you think they are drive wheels it's going to screw the whole thing up. | |||
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"So the speed of the belt is set to match the speed of the plane, not the speed of its wheels? Yes " Ohhhh! In that case, of course it'll take off... | |||
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"I haven't read all the posts so apologies if this has been said before. If the forward momentum was provided by the wheels, then the plane would standstill. However, as the plane uses its jets/propellor to provide the thrust, the plane will still move forward as normal and take off. The wheels effectively do nothing other than hold the plane up and allow it to move over the ground until it reaches enough speed to take off. The only difference the conveyor belt would make is that at any point in the take off the wheels are turning twice as fast as they would be on a normal takeoff. " | |||
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"So the speed of the belt is set to match the speed of the plane, not the speed of its wheels?" Another way of looking at it is the speed of the wheels is proportional to the speed of the plane and the speed of the belt. If you like, the turning of the wheels is a function of plane speed and conveyor speed. | |||
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"So the speed of the belt is set to match the speed of the plane, not the speed of its wheels? It makes no difference either way. " It actually does. It makes the difference between flight or no flight | |||
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"In theory it should take off as the thrust from the engine will push the plane forward irrelevant of what the ground and wheels are doing.. But.... It cannot because the way the question was posed created the following environment.. The assumption is that the belt can travel at an infinite speed and the engines can produce infinite forward motion. The wheels cause drag and the airpressure cause resistance to the forward motion, therefore the plane is unable to overcome the resistance posed by the entire system and will Remain totally static... " no. even on my imaginary gym treadmill, if the treadmill was connected to a 1000 bhp engine and could spin at 500 mph, if it stand on it on my roller skates, I can still pull myself forward as normal with a piece of rope. The belt has no method to produce any rearward force, due to the wheels being in-between. | |||
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"So the speed of the belt is set to match the speed of the plane, not the speed of its wheels? It makes no difference either way. It actually does. It makes the difference between flight or no flight" the belt can turn at a million miles an hour if it wants. The wheels spin backwards at a million miles an hour , the plane will accelerate forward as normal. | |||
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"So the speed of the belt is set to match the speed of the plane, not the speed of its wheels? It makes no difference either way. It actually does. It makes the difference between flight or no flight the belt can turn at a million miles an hour if it wants. The wheels spin backwards at a million miles an hour , the plane will accelerate forward as normal." Well actually,,, there is slight resistance in the wheels at some point the belt will he going fast enough that the resistance is high enough to actually push the plane back... I suspect the wheels will have burst way before that point is reached though! | |||
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"So the speed of the belt is set to match the speed of the plane, not the speed of its wheels? It makes no difference either way. It actually does. It makes the difference between flight or no flight the belt can turn at a million miles an hour if it wants. The wheels spin backwards at a million miles an hour , the plane will accelerate forward as normal." No the wheels would need to be spinning at a million and one miles an hour to move forwards | |||
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"So the speed of the belt is set to match the speed of the plane, not the speed of its wheels? It makes no difference either way. It actually does. It makes the difference between flight or no flight the belt can turn at a million miles an hour if it wants. The wheels spin backwards at a million miles an hour , the plane will accelerate forward as normal. Well actually,,, there is slight resistance in the wheels at some point the belt will he going fast enough that the resistance is high enough to actually push the plane back... I suspect the wheels will have burst way before that point is reached though!" Yes, in the practical real world, the belt can push back on the plane a tiny bit because of the friction in the bearings. The engines just need to work a tiny bit harder to counteract that friction. But its already too complicated. The basic physics is that the moving belt can't slow or stop the plane moving forward. | |||
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"This should resolve the debate https://m.youtube.com/watch?v=YORCk1BN7QY" yayyy 1 Also, my mates Isaac Newton, and prof Brian Cox have profiles on here. Just PM them and ask what they say: I_Suck_Newton Big_Cock_Cox they'll confirm it will fly. | |||
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"Shall we assume friction is negligible and the brakes on the plane main wheels are unserviceable and don't work? Does that change anyone's thought process??" Yes, it can't have it brakes on. If its brakes were on, the belt would move it backwards. But its trying to take off, the brakes are off | |||
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"So the speed of the belt is set to match the speed of the plane, not the speed of its wheels? It makes no difference either way. It actually does. It makes the difference between flight or no flight the belt can turn at a million miles an hour if it wants. The wheels spin backwards at a million miles an hour , the plane will accelerate forward as normal. No the wheels would need to be spinning at a million and one miles an hour to move forwards" Actually wheels spin in rpm not mph a spinning thing can move as a vector in any direction regardless of its spin | |||
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"So the speed of the belt is set to match the speed of the plane, not the speed of its wheels? It makes no difference either way. It actually does. It makes the difference between flight or no flight the belt can turn at a million miles an hour if it wants. The wheels spin backwards at a million miles an hour , the plane will accelerate forward as normal. No the wheels would need to be spinning at a million and one miles an hour to move forwards Actually wheels spin in rpm not mph a spinning thing can move as a vector in any direction regardless of its spin" That doesn't help people who think it can't fly. I'm trying to bring something useful to the table. | |||
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"The belt is irrelevant, as is movement, or engines. " This about any regular size jet. People don't get that it can move forwards on the belt and therefore fly. | |||
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"OK - different example... An aeroplane takes off from a runway in a westerly direction. There is no conveyor belt at all, the runway is stuck on the ground. OK, is that simple enough? But due to the Earth's rotation, the ground surface, and hence the runway, are moving at about 1000 miles per hour in an easterly direction - opposite to the aeroplane's motion.... Can the aeroplane still take off???? Go to any sodding airport - watch the damn thing, and find out!!! Waaaaaa - I give in.... " Yep. Simply because the aircraft, runway, earth are moving relative to each other. It's simply Einsteins man on a train. | |||
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"This problem is exacerbated a lot by it being difficult to get across succinctly what you actually really mean! Does anyone still think it won't take off? " Plenty of people will. | |||
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"In theory it should take off as the thrust from the engine will push the plane forward irrelevant of what the ground and wheels are doing.. But.... It cannot because the way the question was posed created the following environment.. The assumption is that the belt can travel at an infinite speed and the engines can produce infinite forward motion. The wheels cause drag and the airpressure cause resistance to the forward motion, therefore the plane is unable to overcome the resistance posed by the entire system and will Remain totally static... no. even on my imaginary gym treadmill, if the treadmill was connected to a 1000 bhp engine and could spin at 500 mph, if it stand on it on my roller skates, I can still pull myself forward as normal with a piece of rope. The belt has no method to produce any rearward force, due to the wheels being in-between." I toyed with both notions, but based upon the original description, and checked with people that know how, it was confirmed that flight would be practicable impossible.. If full thrust was instantaneous and the belt started slowly, then forward motion would be possible but because they are equal, it can never overcome the external influence of resistance. He then went on to explain the science behind the facts and at which point i dozed off.. It still doesn't make sense to me, as far as I can see, it should be able to take off, but I seem to be missing the importance of the text in the original post... | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?”" I've had a think about this and seen the vids and I think it depends, say the wheels and belt are both going at 50 mph, then the engines are turned on and start to drag in air this will then push the plane to go faster, for arguments sake let's say to 100 mph, so the plane is now being pushed to twice what the belt was originally going, if the belt speed increases to match then no the plane won't take off, if the belt stays the same then yes it will How's that? | |||
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"In theory it should take off as the thrust from the engine will push the plane forward irrelevant of what the ground and wheels are doing.. But.... It cannot because the way the question was posed created the following environment.. The assumption is that the belt can travel at an infinite speed and the engines can produce infinite forward motion. The wheels cause drag and the airpressure cause resistance to the forward motion, therefore the plane is unable to overcome the resistance posed by the entire system and will Remain totally static... no. even on my imaginary gym treadmill, if the treadmill was connected to a 1000 bhp engine and could spin at 500 mph, if it stand on it on my roller skates, I can still pull myself forward as normal with a piece of rope. The belt has no method to produce any rearward force, due to the wheels being in-between. I toyed with both notions, but based upon the original description, and checked with people that know how, it was confirmed that flight would be practicable impossible.. If full thrust was instantaneous and the belt started slowly, then forward motion would be possible but because they are equal, it can never overcome the external influence of resistance. He then went on to explain the science behind the facts and at which point i dozed off.. It still doesn't make sense to me, as far as I can see, it should be able to take off, but I seem to be missing the importance of the text in the original post... " The person you spoke to had no idea ! | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?” I've had a think about this and seen the vids and I think it depends, say the wheels and belt are both going at 50 mph, then the engines are turned on and start to drag in air this will then push the plane to go faster, for arguments sake let's say to 100 mph, so the plane is now being pushed to twice what the belt was originally going, if the belt speed increases to match then no the plane won't take off, if the belt stays the same then yes it will How's that? " wrong | |||
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"Seems a pointless question but the answer is probably not. If the aircrafts thrust is being directly negated by the conveyer belt runway, the thrust is equal to the drag. Therefore no lift is possible. Only when thrust outweighs drag can lift be possible. Basic aerodynamics. The only caveat is that if there is sufficient windspeed, eg. 240mph windspeeds against the direction of the aircrafts thrust, then takeoff would potentially be feasible if the aircraft remains effectively stationery. But the airflow would have to be consistent at that speed for a safe takeoff and that's hardly likely! " Just explain how a conveyer belt pushing upon free spinning wheels can overcome 40 000 pounds of thrust ? | |||
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"So the speed of the belt is set to match the speed of the plane, not the speed of its wheels? It makes no difference either way. It actually does. It makes the difference between flight or no flight" You are either terminally stupid, or just winding everyone up; I shall assume the latter. The wheels , the belt, are completely irrelevant; the only thing that is relevant is that the propeller(s) or the jet(s) are providing thrust to the aircraft body. As soon as that thrust has accelerated the aircraft forward sufficiently for the airflow to create lift which is greater than the aircraft weight, it will take off. | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?”" You say the plane is standing.. therefore no wind passing the wing at speed so no lift can be generated | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?” I've had a think about this and seen the vids and I think it depends, say the wheels and belt are both going at 50 mph, then the engines are turned on and start to drag in air this will then push the plane to go faster, for arguments sake let's say to 100 mph, so the plane is now being pushed to twice what the belt was originally going, if the belt speed increases to match then no the plane won't take off, if the belt stays the same then yes it will How's that? wrong" Ok, how so? | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?” You say the plane is standing.. therefore no wind passing the wing at speed so no lift can be generated " If the pilot powers up I'd say it could take off tho.. the power is not transferred through the wheels like on a car | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?” You say the plane is standing.. therefore no wind passing the wing at speed so no lift can be generated " You read that but missed the plane MOVES in one direction That movement occurs from engine thrust which is then matched by the conveyer in the opposite direction but has NO EFFECT upon the movement of the plane | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?” I've had a think about this and seen the vids and I think it depends, say the wheels and belt are both going at 50 mph, then the engines are turned on and start to drag in air this will then push the plane to go faster, for arguments sake let's say to 100 mph, so the plane is now being pushed to twice what the belt was originally going, if the belt speed increases to match then no the plane won't take off, if the belt stays the same then yes it will How's that? wrong Ok, how so? " Seriously ? | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?” I've had a think about this and seen the vids and I think it depends, say the wheels and belt are both going at 50 mph, then the engines are turned on and start to drag in air this will then push the plane to go faster, for arguments sake let's say to 100 mph, so the plane is now being pushed to twice what the belt was originally going, if the belt speed increases to match then no the plane won't take off, if the belt stays the same then yes it will How's that? wrong Ok, how so? Seriously ?" Yes, you're disagreeing with my reasoning but not giving reasoning of your own, hence my asking | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?” I've had a think about this and seen the vids and I think it depends, say the wheels and belt are both going at 50 mph, then the engines are turned on and start to drag in air this will then push the plane to go faster, for arguments sake let's say to 100 mph, so the plane is now being pushed to twice what the belt was originally going, if the belt speed increases to match then no the plane won't take off, if the belt stays the same then yes it will How's that? wrong Ok, how so? Seriously ? Yes, you're disagreeing with my reasoning but not giving reasoning of your own, hence my asking " You read that but missed the plane MOVES in one direction That movement occurs from engine thrust which is then matched by the conveyer in the opposite direction but has NO EFFECT upon the movement of the plane Which bit of the conveyer has no effect upon the motion of the plane do you seriously not understand | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?” I've had a think about this and seen the vids and I think it depends, say the wheels and belt are both going at 50 mph, then the engines are turned on and start to drag in air this will then push the plane to go faster, for arguments sake let's say to 100 mph, so the plane is now being pushed to twice what the belt was originally going, if the belt speed increases to match then no the plane won't take off, if the belt stays the same then yes it will How's that? wrong Ok, how so? Seriously ? Yes, you're disagreeing with my reasoning but not giving reasoning of your own, hence my asking You read that but missed the plane MOVES in one direction That movement occurs from engine thrust which is then matched by the conveyer in the opposite direction but has NO EFFECT upon the movement of the plane Which bit of the conveyer has no effect upon the motion of the plane do you seriously not understand " The motion of the plane has an effect on the wheels, it'll make them go faster, my point is that if the belt then matches this it will stop the plane taking off because the plane will still be effectively at a standstill, if it dosent it won't because the plane will then beat the belt, how did u not understand that?? | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?” You say the plane is standing.. therefore no wind passing the wing at speed so no lift can be generated You read that but missed the plane MOVES in one direction That movement occurs from engine thrust which is then matched by the conveyer in the opposite direction but has NO EFFECT upon the movement of the plane " I think the plane would still move, power is not transferred through the ground like it would be in a car, the wheels might turn twice as fast as they would normally tho | |||
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"Seems a pointless question but the answer is probably not. If the aircrafts thrust is being directly negated by the conveyer belt runway, the thrust is equal to the drag. Therefore no lift is possible. Only when thrust outweighs drag can lift be possible. Basic aerodynamics. The only caveat is that if there is sufficient windspeed, eg. 240mph windspeeds against the direction of the aircrafts thrust, then takeoff would potentially be feasible if the aircraft remains effectively stationery. But the airflow would have to be consistent at that speed for a safe takeoff and that's hardly likely! Just explain how a conveyer belt pushing upon free spinning wheels can overcome 40 000 pounds of thrust ? " By creating 40000 pounds of drag! Wheels against any surface produces drag. If you have enough drag to counteract the thrust, what do you suppose the result is? Basics of aviaton! | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?”" If the plane dus,not moove from its start poshishoun then regardlis how mutch thrust the engines make if the plan dus not moove fallwood throw the air then Thar will be no air flow under and over the wings thear for it can not take off. But if the convayer belt wos to stop sudnley with the engines at fall thrust it wood be a short take off. | |||
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"Great thread - lets keep the discussion going. Does it fly or not? “A plane is standing on a runway that can move (some sort of band conveyer belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?” I've had a think about this and seen the vids and I think it depends, say the wheels and belt are both going at 50 mph, then the engines are turned on and start to drag in air this will then push the plane to go faster, for arguments sake let's say to 100 mph, so the plane is now being pushed to twice what the belt was originally going, if the belt speed increases to match then no the plane won't take off, if the belt stays the same then yes it will How's that? wrong Ok, how so? Seriously ? Yes, you're disagreeing with my reasoning but not giving reasoning of your own, hence my asking You read that but missed the plane MOVES in one direction That movement occurs from engine thrust which is then matched by the conveyer in the opposite direction but has NO EFFECT upon the movement of the plane Which bit of the conveyer has no effect upon the motion of the plane do you seriously not understand The motion of the plane has an effect on the wheels, it'll make them go faster, my point is that if the belt then matches this it will stop the plane taking off because the plane will still be effectively at a standstill, if it dosent it won't because the plane will then beat the belt, how did u not understand that?? " how on earth can you come to that conclusion? The conveyor belt and the wheels are totally, utterly irrelevant. All that matters is that the jets or propellers provide forward thrust to the aircraft, which moves forward, irrespective of what the wheels or the conveyor belt is doing. Once the wings are moving forward fast enough to provide lift, the aircraft takes off. The conveyor belt and the wheels have nothing to do with the engines and the thrust on the aircraft; | |||
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"I am fairly certain that under some circumstances then this plane could definitely take off. The definition of 'take off' may mean something different to the first element of a succesful transatlantic flight of course, so it's also worthwhile taking note of that. If there were more elements controlling the potential uplift of the plane, then it would be more difficult. With the major limitation being the conveyor belt and its control system, then a couple of things spring immediately to mind: firstly that the monitoring gets the conveyor belt to respond in arrears to what the plane has achieved. As it's in arrears, then it's playing catchup: thus the plane could achieve actual take-off, before the delayed response from the belt. In essence, there only needs to be one nano second of delay and that may well be the nano second that the plane takes off. I sense that there could be so many extraneous factors that could influence positively the achievement of take-off, with just a delayed response from the actual belt itself that the odds are highly in favour of the plane getting there. The amount of energy, its availability, gradients etc, as well as the physical conditions in situ, will all influence the potential for the plane to take off. " The belt is irrelevant, there is no force from the belt transferred to the plane...it (the rearward force created by the belt) cannot travel any further than the wheels. | |||
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" Ok let's come at this in the spirit of the hypothetical as it was posed Plane and belt move in opposite directions in perfect synchronicity The landing gear, i.e. Wheels do not provide drive they support the mass (weight) of the plane whilst stationary Therefore if the belt and plane move simultaneously the airflow does not provide lift and therefore weight is still transferring down to the wheels keeping it on the ground The only way to break the cycle is if the plane accelerates past the force in reverse of the belt and creates forward motion thus airflow, cancelling weight and allowing lift Everyone have a drink and chill the fuck out " But in this you are agreeing the plane is moving forward. If the plane is moving forward it has airflow over the wings. It then takes off. The belt has no effect on anything. | |||
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" Ok let's come at this in the spirit of the hypothetical as it was posed Plane and belt move in opposite directions in perfect synchronicity The landing gear, i.e. Wheels do not provide drive they support the mass (weight) of the plane whilst stationary Therefore if the belt and plane move simultaneously the airflow does not provide lift and therefore weight is still transferring down to the wheels keeping it on the ground The only way to break the cycle is if the plane accelerates past the force in reverse of the belt and creates forward motion thus airflow, cancelling weight and allowing lift Everyone have a drink and chill the fuck out But in this you are agreeing the plane is moving forward. If the plane is moving forward it has airflow over the wings. It then takes off. The belt has no effect on anything." No, the plane is accelerating but forward motion is cancelled due to the belt matching the acceleration. The weight cannot be transferred into velocity creating airflow so no lift. The planes position is exactly the same. If you had a gps point it would not move in this case. Remember the treadmill? You stay in the same overall position. | |||
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"I'll repost: Right, lets forget the plane for a minute. Back to the gym. Stand on the treadmill wearing roller skates. There is a rope tied to the wall in front of you. You hold the rope gently. you switch the treadmill on. You stay motionless. You speed the treadmill up. You stay motionless. You speed the treadmill up to 200mph. You stay motionless. You pull on the rope gently. you move forwards, same as on the floor. . . You are the plane. roller skates are its wheels. engines are the rope The plane moves forward exactly as normal. It gets up to full speed as normal and takes off as normal" Gets my vote | |||
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" Fuck me... ok then simple logic question then Why haven't all the huge spaces of runways been replaced by fucking belts?? Thank you.... I'm out " Clearly these engineers are fuckwits and fab swingers have the answers pmsl | |||
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" Ok let's come at this in the spirit of the hypothetical as it was posed Plane and belt move in opposite directions in perfect synchronicity The landing gear, i.e. Wheels do not provide drive they support the mass (weight) of the plane whilst stationary Therefore if the belt and plane move simultaneously the airflow does not provide lift and therefore weight is still transferring down to the wheels keeping it on the ground The only way to break the cycle is if the plane accelerates past the force in reverse of the belt and creates forward motion thus airflow, cancelling weight and allowing lift Everyone have a drink and chill the fuck out But in this you are agreeing the plane is moving forward. If the plane is moving forward it has airflow over the wings. It then takes off. The belt has no effect on anything. No, the plane is accelerating but forward motion is cancelled due to the belt matching the acceleration. The weight cannot be transferred into velocity creating airflow so no lift. The planes position is exactly the same. If you had a gps point it would not move in this case. Remember the treadmill? You stay in the same overall position." For crying out loud how does the belt match the acceleration of the air!!!!?, THE BELT US IRRELEVANT BECAUSE THE WHEELS BREAK THE CHAIN BETWEEN THE BELT AND THE PLANE THE BELT CANNOT INFLUENCE THE PLANE IN ANY WAY WHATSOEVER!! | |||
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" Ok let's come at this in the spirit of the hypothetical as it was posed Plane and belt move in opposite directions in perfect synchronicity The landing gear, i.e. Wheels do not provide drive they support the mass (weight) of the plane whilst stationary Therefore if the belt and plane move simultaneously the airflow does not provide lift and therefore weight is still transferring down to the wheels keeping it on the ground The only way to break the cycle is if the plane accelerates past the force in reverse of the belt and creates forward motion thus airflow, cancelling weight and allowing lift Everyone have a drink and chill the fuck out But in this you are agreeing the plane is moving forward. If the plane is moving forward it has airflow over the wings. It then takes off. The belt has no effect on anything. No, the plane is accelerating but forward motion is cancelled due to the belt matching the acceleration. The weight cannot be transferred into velocity creating airflow so no lift. The planes position is exactly the same. If you had a gps point it would not move in this case. Remember the treadmill? You stay in the same overall position. For crying out loud how does the belt match the acceleration of the air!!!!?, THE BELT US IRRELEVANT BECAUSE THE WHEELS BREAK THE CHAIN BETWEEN THE BELT AND THE PLANE THE BELT CANNOT INFLUENCE THE PLANE IN ANY WAY WHATSOEVER!!" What are you talking about acceleration of the air??? The belt is pulling the weight of the plane backwards and only being cancelled out by the acceleration of the planes engines in the opposite direction.. so... it just trundles... however fast you want! along in the SAME overall position No airflow over the wings because position wise it's NOT FUCKING MOVING The air is doing fuck all except going through the thrust ports of the engine. Forget all the technical aruguments.. I refer you to the above... why are all these silly airports wasting land space? Shortage of rubber maybe.. fuck me | |||
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" Ok let's come at this in the spirit of the hypothetical as it was posed Plane and belt move in opposite directions in perfect synchronicity The landing gear, i.e. Wheels do not provide drive they support the mass (weight) of the plane whilst stationary Therefore if the belt and plane move simultaneously the airflow does not provide lift and therefore weight is still transferring down to the wheels keeping it on the ground The only way to break the cycle is if the plane accelerates past the force in reverse of the belt and creates forward motion thus airflow, cancelling weight and allowing lift Everyone have a drink and chill the fuck out But in this you are agreeing the plane is moving forward. If the plane is moving forward it has airflow over the wings. It then takes off. The belt has no effect on anything. No, the plane is accelerating but forward motion is cancelled due to the belt matching the acceleration. The weight cannot be transferred into velocity creating airflow so no lift. The planes position is exactly the same. If you had a gps point it would not move in this case. Remember the treadmill? You stay in the same overall position. For crying out loud how does the belt match the acceleration of the air!!!!?, THE BELT US IRRELEVANT BECAUSE THE WHEELS BREAK THE CHAIN BETWEEN THE BELT AND THE PLANE THE BELT CANNOT INFLUENCE THE PLANE IN ANY WAY WHATSOEVER!! What are you talking about acceleration of the air??? The belt is pulling the weight of the plane backwards and only being cancelled out by the acceleration of the planes engines in the opposite direction.. so... it just trundles... however fast you want! along in the SAME overall position No airflow over the wings because position wise it's NOT FUCKING MOVING The air is doing fuck all except going through the thrust ports of the engine. Forget all the technical aruguments.. I refer you to the above... why are all these silly airports wasting land space? Shortage of rubber maybe.. fuck me " FFS the belt is NOT pulling the weight of the plane backwards!!! | |||
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"What are you talking about acceleration of the air??? The belt is pulling the weight of the plane backwards and only being cancelled out by the acceleration of the planes engines in the opposite direction.. so... it just trundles... however fast you want! along in the SAME overall position No airflow over the wings because position wise it's NOT FUCKING MOVING The air is doing fuck all except going through the thrust ports of the engine. Forget all the technical aruguments.. I refer you to the above... why are all these silly airports wasting land space? Shortage of rubber maybe.. fuck me " You're still trying? Anyone who cannot see that two equal and opposite motions will cancel each other out does not deserve your help | |||
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"What are you talking about acceleration of the air??? The belt is pulling the weight of the plane backwards and only being cancelled out by the acceleration of the planes engines in the opposite direction.. so... it just trundles... however fast you want! along in the SAME overall position No airflow over the wings because position wise it's NOT FUCKING MOVING The air is doing fuck all except going through the thrust ports of the engine. Forget all the technical aruguments.. I refer you to the above... why are all these silly airports wasting land space? Shortage of rubber maybe.. fuck me You're still trying? Anyone who cannot see that two equal and opposite motions will cancel each other out does not deserve your help" Ha ha true.. fuck it it's Friday hot sex and cocktails for everyone!! Forget all this technical mind bending and go bend someone over for a good un! Ps I will be looking out for all these people flying out of gym windows on their treadmills and expect delays at Glasgow airport as they install all the belts to save land space | |||
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"Mavrik Nobody is saying the plane stand still and suddenly floats up. It moves forward exactly as normal for the mile or whatever. It doesnt matter if underneath it is tarmac or a belt." Hey Bun I no longer care... I'm now focusing on more lovely Friday things... such as your lovely tooshy bent over that bed | |||
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"Lol Are we nearly ready for a Vol 3???" Don't you fucking dare!!! Lol driving me nuts | |||
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"I can't read all this thread. Can someone make me an audio book, preferably read by Stephen Fry......!!" You'd be better with Stephen hawking to convince some folk on here! | |||
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