MythBusters

[smack Down]

Originally posted by: DanTMWTMP
I've never seen a more dense person who refuses to thoroughly read anything than Jandrews.

The argument isn't about wind going over the wings. It's about the plane moving foward in relation to a point outside of the threadmill/plane model. In relation to this point, the plane moves forward as if the treadmill is nonexistent. Numerous youtube videos already show that the plane moves foward. Engines act on the air, not on the ground.

A Car WILL stay stationary
A plane will not.

I have no idea why you are so stupidly dense not to realize this utterly simple riddle.

You are completely wrong. A Car and plane will behave identical on a treadmill.

AS for the physics lets pretend that we have two cars that have the same mass(m), same moment of inertia(i), and no friction. For the sake of simplicity lets take the acceleration at 1 m/s/s

On a road do you agree that they would reach a speed of 1 m/s after one second of driving? and both have the same amount of kinetic energy? 1 * m + 1 * i

Ok now lets put our two cars on the same treadmill. Your theory is the the rocket car will still accelerate at 1 m/s/s (or some other value greater then zero) and the engine car will accelerate at 0 m/s/s (that is stay in place). Correct? Additional you claim that the treadmill will be going backwards at a minimum of 1 m/s/s (In reality it would be going faster then this. The speed depends on the mass of the car. 1 m/s/s is only true with a car of zero mass.)

The rocket car energy is 1 * m + i * (1 + Vtreadmill)^2.
The normal car has an energy is 0 *m + i * Vtreadmill^2

Remember that in the 1 second on the road they had the same energy and now the rocket car has much more energy when both are required to be equal and equal to the original 1 * m + 1 * i. There is no way a plane can behave differently then the car.

 

[spamsk8r]

I must have missed something, because everybody is saying that the plane will take off, when it absolutely will not. Is my sarcasm detector broken?

 

[JujuFish]

Originally posted by: spamsk8r
I must have missed something, because everybody is saying that the plane will take off, when it absolutely will not. Is my sarcasm detector broken?

I hope you're being sarcastic, because if not, you're absolutely wrong.

I'll bet you $1,000 the plane takes off.

 

[newmachineoverlord]

Originally posted by: jagec

Originally posted by: newmachineoverlord
They would have to do it in a vacuum chamber to meet the conditions specified by the post here with pollage, which specified that there would be "no airflow to the lift generating parts of the plane."

Where did you get THAT idea?

Whether or not the plane takes off depends entirely on the nuances in the phrasing of the question.

The original formulations posted here in off topic stipulated a lack of airflow over lift generating parts of the plane. Despite this stipulation more than 70 % of ATOTers said it would take off anyways, thus proving that most people don't bother to read the details or are unaware that airflow is required to generate lift. I can't seem to find the poll with search, but the following was the original OT posting.


http://forums.anandtech.com/me...ey=y&keyword1=conveyor
[
"The plane increases it's thrust and the wheels begin to rotate. The belt compensates for #1 the forward rotation of the wheels or #2 the forward movement of the plane, as in the belt moves in reverse exactly as fast as condition #1 or #2

And if it matters, it's a nice sunny day and you have good tires, so you get perfect traction on the belt at all times. Your plane also happens to be very powerful and you can give it as much thrust as you like, but
the source of thrust is at the back of the plane so it never provides airflow over the wing.
Does the plane take off using #1?
Does the plane take off using #2?

EDITED: There are two interpretations to the question, #1 or #2. It's best you clarify which of the two conditions you have in mind when making your argument. If you're familiar with the original interpretation of the question, it would be #2."

Edit: added quotation marks

 

[timosyy]

Originally posted by: newmachineoverlord

And if it matters, it's a nice sunny day and you have good tires, so you get perfect traction on the belt at all times. Your plane also happens to be very powerful and you can give it as much thrust as you like, but
the source of thrust is at the back of the plane so it never provides airflow over the wing.

I feel like you've misinterpreted. When I read that, I read that the thrust (engines) are generating thrust from the back of the plane (so say, engines on a jet instead of a propeller at the front of the plane), and the air from the thrust isn't going over the wings.

That thrust (while not going over the wings) would still push an airplane forward on a conveyor belt (since the wheels are free rolling and don't really matter once you overcome the rotational friction), and THEN there would be lift from the air going under the wings as the plane moves forward.

 

[BeauJangles]

Originally posted by: newmachineoverlord

Originally posted by: jagec

Originally posted by: newmachineoverlord
They would have to do it in a vacuum chamber to meet the conditions specified by the post here with pollage, which specified that there would be "no airflow to the lift generating parts of the plane."

Where did you get THAT idea?

Whether or not the plane takes off depends entirely on the nuances in the phrasing of the question.

The original formulations posted here in off topic stipulated a lack of airflow over lift generating parts of the plane. Despite this stipulation more than 70 % of ATOTers said it would take off anyways, thus proving that most people don't bother to read the details or are unaware that airflow is required to generate lift. I can't seem to find the poll with search, but the following was the original OT posting.


http://forums.anandtech.com/me...ey=y&keyword1=conveyor
[
"The plane increases it's thrust and the wheels begin to rotate. The belt compensates for #1 the forward rotation of the wheels or #2 the forward movement of the plane, as in the belt moves in reverse exactly as fast as condition #1 or #2

And if it matters, it's a nice sunny day and you have good tires, so you get perfect traction on the belt at all times. Your plane also happens to be very powerful and you can give it as much thrust as you like, but
the source of thrust is at the back of the plane so it never provides airflow over the wing.
Does the plane take off using #1?
Does the plane take off using #2?

EDITED: There are two interpretations to the question, #1 or #2. It's best you clarify which of the two conditions you have in mind when making your argument. If you're familiar with the original interpretation of the question, it would be #2."

Edit: added quotation marks

#1 is impossible. The wheel-speed would quickly increase to infinity.

 

[randay]

Originally posted by: BlinderBomber

Originally posted by: newmachineoverlord

Originally posted by: jagec

Originally posted by: newmachineoverlord
They would have to do it in a vacuum chamber to meet the conditions specified by the post here with pollage, which specified that there would be "no airflow to the lift generating parts of the plane."

Where did you get THAT idea?

Whether or not the plane takes off depends entirely on the nuances in the phrasing of the question.

The original formulations posted here in off topic stipulated a lack of airflow over lift generating parts of the plane. Despite this stipulation more than 70 % of ATOTers said it would take off anyways, thus proving that most people don't bother to read the details or are unaware that airflow is required to generate lift. I can't seem to find the poll with search, but the following was the original OT posting.


http://forums.anandtech.com/me...ey=y&keyword1=conveyor
[
"The plane increases it's thrust and the wheels begin to rotate. The belt compensates for #1 the forward rotation of the wheels or #2 the forward movement of the plane, as in the belt moves in reverse exactly as fast as condition #1 or #2

And if it matters, it's a nice sunny day and you have good tires, so you get perfect traction on the belt at all times. Your plane also happens to be very powerful and you can give it as much thrust as you like, but
the source of thrust is at the back of the plane so it never provides airflow over the wing.
Does the plane take off using #1?
Does the plane take off using #2?

EDITED: There are two interpretations to the question, #1 or #2. It's best you clarify which of the two conditions you have in mind when making your argument. If you're familiar with the original interpretation of the question, it would be #2."

Edit: added quotation marks

#1 is impossible. The wheel-speed would quickly increase to infinity.

Nothing is impossible. Not if you can imagine it!

 

[sdifox]

Originally posted by: smack Down

Originally posted by: DanTMWTMP
I've never seen a more dense person who refuses to thoroughly read anything than Jandrews.

The argument isn't about wind going over the wings. It's about the plane moving foward in relation to a point outside of the threadmill/plane model. In relation to this point, the plane moves forward as if the treadmill is nonexistent. Numerous youtube videos already show that the plane moves foward. Engines act on the air, not on the ground.

A Car WILL stay stationary
A plane will not.

I have no idea why you are so stupidly dense not to realize this utterly simple riddle.

You are completely wrong. A Car and plane will behave identical on a treadmill.

AS for the physics lets pretend that we have two cars that have the same mass(m), same moment of inertia(i), and no friction. For the sake of simplicity lets take the acceleration at 1 m/s/s

On a road do you agree that they would reach a speed of 1 m/s after one second of driving? and both have the same amount of kinetic energy? 1 * m + 1 * i

Ok now lets put our two cars on the same treadmill. Your theory is the the rocket car will still accelerate at 1 m/s/s (or some other value greater then zero) and the engine car will accelerate at 0 m/s/s (that is stay in place). Correct? Additional you claim that the treadmill will be going backwards at a minimum of 1 m/s/s (In reality it would be going faster then this. The speed depends on the mass of the car. 1 m/s/s is only true with a car of zero mass.)

The rocket car energy is 1 * m + i * (1 + Vtreadmill)^2.
The normal car has an energy is 0 *m + i * Vtreadmill^2

Remember that in the 1 second on the road they had the same energy and now the rocket car has much more energy when both are required to be equal and equal to the original 1 * m + 1 * i. There is no way a plane can behave differently then the car.

err, we are talking about how the energy is used. car torques the wheels to move forward, plane does not torque the wheel to move forward. Otherwise we would have no airplanes!

 

[hiromizu]

You Morons. The plane explodes.

 

[sdifox]

Originally posted by: JujuFish

Originally posted by: spamsk8r
I must have missed something, because everybody is saying that the plane will take off, when it absolutely will not. Is my sarcasm detector broken?

I hope you're being sarcastic, because if not, you're absolutely wrong.

I'll bet you $1,000 the plane takes off.

Can I borrow a salmon so I can fish-slap all those who believe in alternative physics?

 

[MegaVovaN]

Originally posted by: sdifox

Originally posted by: JujuFish

Originally posted by: spamsk8r
I must have missed something, because everybody is saying that the plane will take off, when it absolutely will not. Is my sarcasm detector broken?

I hope you're being sarcastic, because if not, you're absolutely wrong.

I'll bet you $1,000 the plane takes off.

Can I borrow a salmon so I can fish-slap all those who believe in alternative physics?

Here is a truckload of large salmon buddy. Good luck on slappin these idiots thinking plane will not take off :roll:

It does take off you dumbwits :thumbsdown:

 

[waggy]

Originally posted by: sdifox

Originally posted by: smack Down

Originally posted by: DanTMWTMP
I've never seen a more dense person who refuses to thoroughly read anything than Jandrews.

The argument isn't about wind going over the wings. It's about the plane moving foward in relation to a point outside of the threadmill/plane model. In relation to this point, the plane moves forward as if the treadmill is nonexistent. Numerous youtube videos already show that the plane moves foward. Engines act on the air, not on the ground.

A Car WILL stay stationary
A plane will not.

I have no idea why you are so stupidly dense not to realize this utterly simple riddle.

You are completely wrong. A Car and plane will behave identical on a treadmill.

AS for the physics lets pretend that we have two cars that have the same mass(m), same moment of inertia(i), and no friction. For the sake of simplicity lets take the acceleration at 1 m/s/s

On a road do you agree that they would reach a speed of 1 m/s after one second of driving? and both have the same amount of kinetic energy? 1 * m + 1 * i

Ok now lets put our two cars on the same treadmill. Your theory is the the rocket car will still accelerate at 1 m/s/s (or some other value greater then zero) and the engine car will accelerate at 0 m/s/s (that is stay in place). Correct? Additional you claim that the treadmill will be going backwards at a minimum of 1 m/s/s (In reality it would be going faster then this. The speed depends on the mass of the car. 1 m/s/s is only true with a car of zero mass.)

The rocket car energy is 1 * m + i * (1 + Vtreadmill)^2.
The normal car has an energy is 0 *m + i * Vtreadmill^2

Remember that in the 1 second on the road they had the same energy and now the rocket car has much more energy when both are required to be equal and equal to the original 1 * m + 1 * i. There is no way a plane can behave differently then the car.

err, we are talking about how the energy is used. car torques the wheels to move forward, plane does not torque the wheel to move forward. Otherwise we would have no airplanes!

good luck. smackdown is a idiot. anyone who thinks a car and airplane behave identical is a idiot.
IF they did operate the same we all would have flying cars by now!

 

[sdifox]

Originally posted by: HydroSqueegee
ok.. after going through and actually reading the thread and getting a fresh understanding of what the myth actually is, i'll have to shift to the camp that the plane will take off. As long as the plane has enough thrust to overcome the wheel friction, it should go down the conveyor with enough speed to take off.

one down, seven billion to go...

 

[sdifox]

Originally posted by: Skeeedunt

Originally posted by: ConstipatedVigilante

Originally posted by: sdifox

Originally posted by: SSSnail

Originally posted by: sdifox

Originally posted by: ConstipatedVigilante
I don't think I've ever seen the myth explained specifically enough. In some cases, the plane would take off, while in others it wouldn't.

If the treadmill is only as big as the plane can fit on it, it will obviously not take off due to a lack of wind resistance (it can't move forward).

If the treadmill is of infinite or runway length, then the plane's engines will easily overcome the force of the treadmill on the wheels, thus it moves forwards and takes off.

make up your mind... if it is not going to take off since it remains stationary, what difference does it make how long the treadmill is?

It... uhh... actually kinda... uhh... does, because after overcoming the initial friction of the wheels, ze plane still has to reach it's required airspeed to take off, so if ze runway is too short, ze plane does not take off...

The problem is not about the plane falling off the conveyor belt, it's about whether it can keep the plane from taking off.

Well, it can't take off if it's falling off, now can it?

This is a new and exciting scenario. A plane is stationed on an infinitely small treadmill at the edge of a cliff. Assuming the ground at the bottom is frictionless, will the plane take off?

My only hope is that the conveyor plane has to face off against a frozen chicken.

err, a plane cannot be on a infinitely small treadmill...unless you have a infinitely small plane, which gets you back to the original problem.

 

[hiromizu]

What really happens is the plane's front wheels will lock up preventing the pilot from making corrections in yaw drift during the take off run causing the plane to veer off the treadmill and crash. Another possibility due to the plane's wheels having to turn much faster than designed for the plane to ever achieve the required take off airspeed, the wheel bearings will catch fire, wheels breaking off and causing the plane to crash n burn.

 

[sandorski]

Haven't read this thread in approx 1 month, but I'll throw this out there anyway: The Plane doesn't even need to move forward for it to Take Off! Once enough airflow is achieved on the wings, it will simply rise into the air. One problem with that I'm not sure if any aircraft in existence has that kind of thrust. However, if you put a Jet Engine on a Cessna it'd achieve flight faster than you could read this post. Infinitely fast Treadmill or not.

*******Warning Read through next 4 or 5 posts by me before responding********

 

[Venix]

Originally posted by: smack Down

Originally posted by: DanTMWTMP
I've never seen a more dense person who refuses to thoroughly read anything than Jandrews.

The argument isn't about wind going over the wings. It's about the plane moving foward in relation to a point outside of the threadmill/plane model. In relation to this point, the plane moves forward as if the treadmill is nonexistent. Numerous youtube videos already show that the plane moves foward. Engines act on the air, not on the ground.

A Car WILL stay stationary
A plane will not.

I have no idea why you are so stupidly dense not to realize this utterly simple riddle.

You are completely wrong. A Car and plane will behave identical on a treadmill.

I agree that DanTMWTMP is completely wrong. You are far denser than jandrews.

An RC plane on a treadmill moves forward at the same rate regardless of the speed of the treadmill. The treadmill at 10 mph is moving far faster than the plane, yet the plane still moves.

And here the same guy demonstrates how to keep the plane in one place while the treadmill is moving at any speed. Notice that the plane doesn't move even when the treadmill speed is doubled.

If you seriously believe that an RC car would behave identically, you are an idiot.

 

[LegendKiller]

Give it up. These guys have no concept of jet engine thrust acting upon the air, not the treadmill, pushing the plane. I asked the smartest person I know in physics, he has two masters degrees in nuclear engineering and a MechEng from USC, Summa Cum Laude all of them. He says that anybody who thinks the plane will not take off is mentally deficient.

 

[Jeff7]

Originally posted by: sandorski
Haven't read this thread in approx 1 month, but I'll throw this out there anyway: The Plane doesn't even need to move forward for it to Take Off! Once enough airflow is achieved on the wings, it will simply rise into the air. One problem with that I'm not sure if any aircraft in existence has that kind of thrust. However, if you put a Jet Engine on a Cessna it'd achieve flight faster than you could read this post. Infinitely fast Treadmill or not.

Except that this isn't how a plane works. The engine or propeller just pushes or pulls the plane through the air. The air moving over the wings is what then produces lift, courtesy of the airfoil. You could pull an engineless plane along with a team of pickup trucks, and once they reach its takeoff speed, the plane would take off. Then of course, without any continuing source of thrust to fight wind resistance, it would quickly land again.

Originally posted by: LegendKiller
Give it up. These guys have no concept of jet engine thrust acting upon the air, not the treadmill, pushing the plane. I asked the smartest person I know in physics, he has two masters degrees in nuclear engineering and a MechEng from USC, Summa Cum Laude all of them. He says that anybody who thinks the plane will not take off is mentally deficient.

The best part is, I'm pretty sure that this problem could be easily solved with statics, which I learned during my freshman year. If you want to take it up a notch (bam!), then use dynamics, which I had sophomore year, and account for (minor) things like the rotational inertia of the wheels.

It's like when they tested the myth of a bunch of birds in a truck - if you have 20 birds in an enclosed truck, and they all take off, will the truck get lighter? Obviously not, as the amount of mass within the truck has not changed. People didn't get it, that the weight of the birds in flight is then transferred to the air in the truck, and the air is of course producing a force upon the truck. Birds resting vs birds in flight = same mass in the same volume = same weight. Different weight distribution, but still the same weight.

 

[BeauJangles]

Originally posted by: LegendKiller
Give it up. These guys have no concept of jet engine thrust acting upon the air, not the treadmill, pushing the plane. I asked the smartest person I know in physics, he has two masters degrees in nuclear engineering and a MechEng from USC, Summa Cum Laude all of them. He says that anybody who thinks the plane will not take off is mentally deficient.

I think its easy to be misled at first, but after it's been explained I don't understand how anybody can doubt the plane's ability to take off.

 

[GollyGollyGooGooPoo]

bernoulli effect

 

[sandorski]

Originally posted by: Jeff7

Originally posted by: sandorski
Haven't read this thread in approx 1 month, but I'll throw this out there anyway: The Plane doesn't even need to move forward for it to Take Off! Once enough airflow is achieved on the wings, it will simply rise into the air. One problem with that I'm not sure if any aircraft in existence has that kind of thrust. However, if you put a Jet Engine on a Cessna it'd achieve flight faster than you could read this post. Infinitely fast Treadmill or not.

Except that this isn't how a plane works. The engine or propeller just pushes or pulls the plane through the air. The air moving over the wings is what then produces lift, courtesy of the airfoil. You could pull an engineless plane along with a team of pickup trucks, and once they reach its takeoff speed, the plane would take off. Then of course, without any continuing source of thrust to fight wind resistance, it would quickly land again.

Originally posted by: LegendKiller
Give it up. These guys have no concept of jet engine thrust acting upon the air, not the treadmill, pushing the plane. I asked the smartest person I know in physics, he has two masters degrees in nuclear engineering and a MechEng from USC, Summa Cum Laude all of them. He says that anybody who thinks the plane will not take off is mentally deficient.

The best part is, I'm pretty sure that this problem could be easily solved with statics, which I learned during my freshman year. If you want to take it up a notch (bam!), then use dynamics, which I had sophomore year, and account for (minor) things like the rotational inertia of the wheels.

It's like when they tested the myth of a bunch of birds in a truck - if you have 20 birds in an enclosed truck, and they all take off, will the truck get lighter? Obviously not, as the amount of mass within the truck has not changed. People didn't get it, that the weight of the birds in flight is then transferred to the air in the truck, and the air is of course producing a force upon the truck. Birds resting vs birds in flight = same mass in the same volume = same weight. Different weight distribution, but still the same weight.

Wrong. Propellers/Jet engines create the flow of Air over the wings.

edit:upon further reflection, it does both, not just one or the other.

 

[Venix]

Originally posted by: sandorski

Originally posted by: Jeff7

Originally posted by: sandorski
Haven't read this thread in approx 1 month, but I'll throw this out there anyway: The Plane doesn't even need to move forward for it to Take Off! Once enough airflow is achieved on the wings, it will simply rise into the air. One problem with that I'm not sure if any aircraft in existence has that kind of thrust. However, if you put a Jet Engine on a Cessna it'd achieve flight faster than you could read this post. Infinitely fast Treadmill or not.

Except that this isn't how a plane works. The engine or propeller just pushes or pulls the plane through the air. The air moving over the wings is what then produces lift, courtesy of the airfoil. You could pull an engineless plane along with a team of pickup trucks, and once they reach its takeoff speed, the plane would take off. Then of course, without any continuing source of thrust to fight wind resistance, it would quickly land again.

Originally posted by: LegendKiller
Give it up. These guys have no concept of jet engine thrust acting upon the air, not the treadmill, pushing the plane. I asked the smartest person I know in physics, he has two masters degrees in nuclear engineering and a MechEng from USC, Summa Cum Laude all of them. He says that anybody who thinks the plane will not take off is mentally deficient.

The best part is, I'm pretty sure that this problem could be easily solved with statics, which I learned during my freshman year. If you want to take it up a notch (bam!), then use dynamics, which I had sophomore year, and account for (minor) things like the rotational inertia of the wheels.

It's like when they tested the myth of a bunch of birds in a truck - if you have 20 birds in an enclosed truck, and they all take off, will the truck get lighter? Obviously not, as the amount of mass within the truck has not changed. People didn't get it, that the weight of the birds in flight is then transferred to the air in the truck, and the air is of course producing a force upon the truck. Birds resting vs birds in flight = same mass in the same volume = same weight. Different weight distribution, but still the same weight.

Wrong. Propellers/Jet engines create the flow of Air over the wings.

Are you actually suggesting a plane flies because the engines push air over the wings? Not because the engines cause the plane to move forward through the air?

 

[sandorski]

Originally posted by: Venix

Originally posted by: sandorski

Originally posted by: Jeff7

Originally posted by: sandorski
Haven't read this thread in approx 1 month, but I'll throw this out there anyway: The Plane doesn't even need to move forward for it to Take Off! Once enough airflow is achieved on the wings, it will simply rise into the air. One problem with that I'm not sure if any aircraft in existence has that kind of thrust. However, if you put a Jet Engine on a Cessna it'd achieve flight faster than you could read this post. Infinitely fast Treadmill or not.

Except that this isn't how a plane works. The engine or propeller just pushes or pulls the plane through the air. The air moving over the wings is what then produces lift, courtesy of the airfoil. You could pull an engineless plane along with a team of pickup trucks, and once they reach its takeoff speed, the plane would take off. Then of course, without any continuing source of thrust to fight wind resistance, it would quickly land again.

Originally posted by: LegendKiller
Give it up. These guys have no concept of jet engine thrust acting upon the air, not the treadmill, pushing the plane. I asked the smartest person I know in physics, he has two masters degrees in nuclear engineering and a MechEng from USC, Summa Cum Laude all of them. He says that anybody who thinks the plane will not take off is mentally deficient.

The best part is, I'm pretty sure that this problem could be easily solved with statics, which I learned during my freshman year. If you want to take it up a notch (bam!), then use dynamics, which I had sophomore year, and account for (minor) things like the rotational inertia of the wheels.

It's like when they tested the myth of a bunch of birds in a truck - if you have 20 birds in an enclosed truck, and they all take off, will the truck get lighter? Obviously not, as the amount of mass within the truck has not changed. People didn't get it, that the weight of the birds in flight is then transferred to the air in the truck, and the air is of course producing a force upon the truck. Birds resting vs birds in flight = same mass in the same volume = same weight. Different weight distribution, but still the same weight.

Wrong. Propellers/Jet engines create the flow of Air over the wings.

Are you actually suggesting a plane flies because the engines push air over the wings? Not because the engines cause the plane to move forward through the air?

to a large extent, especially initially, yes.

edit: see my edit on other post for refinement

 

[Venix]

Originally posted by: sandorski

Originally posted by: Venix

Originally posted by: sandorski

Originally posted by: Jeff7

Originally posted by: sandorski
Haven't read this thread in approx 1 month, but I'll throw this out there anyway: The Plane doesn't even need to move forward for it to Take Off! Once enough airflow is achieved on the wings, it will simply rise into the air. One problem with that I'm not sure if any aircraft in existence has that kind of thrust. However, if you put a Jet Engine on a Cessna it'd achieve flight faster than you could read this post. Infinitely fast Treadmill or not.

Except that this isn't how a plane works. The engine or propeller just pushes or pulls the plane through the air. The air moving over the wings is what then produces lift, courtesy of the airfoil. You could pull an engineless plane along with a team of pickup trucks, and once they reach its takeoff speed, the plane would take off. Then of course, without any continuing source of thrust to fight wind resistance, it would quickly land again.

Originally posted by: LegendKiller
Give it up. These guys have no concept of jet engine thrust acting upon the air, not the treadmill, pushing the plane. I asked the smartest person I know in physics, he has two masters degrees in nuclear engineering and a MechEng from USC, Summa Cum Laude all of them. He says that anybody who thinks the plane will not take off is mentally deficient.

The best part is, I'm pretty sure that this problem could be easily solved with statics, which I learned during my freshman year. If you want to take it up a notch (bam!), then use dynamics, which I had sophomore year, and account for (minor) things like the rotational inertia of the wheels.

It's like when they tested the myth of a bunch of birds in a truck - if you have 20 birds in an enclosed truck, and they all take off, will the truck get lighter? Obviously not, as the amount of mass within the truck has not changed. People didn't get it, that the weight of the birds in flight is then transferred to the air in the truck, and the air is of course producing a force upon the truck. Birds resting vs birds in flight = same mass in the same volume = same weight. Different weight distribution, but still the same weight.

Wrong. Propellers/Jet engines create the flow of Air over the wings.

Are you actually suggesting a plane flies because the engines push air over the wings? Not because the engines cause the plane to move forward through the air?

to a large extent, especially initially, yes.

edit: see my edit on other post for refinement

Care to explain how the F-16 flies? That engine right in the middle of the body sure isn't blowing or sucking any air over the wings.

In any case, there are a couple of planes that mount the jets above the wings to exploit the Coanda effect from the exhaust and generate some additional lift. They still require a runway, and would drop like a rock at 0 airspeed.