Imagine a plane is sitting on a conveyor belt, can it take off?

[TheGrundle]

Originally Posted by Saint Marcos

To be clear, I completely understand that the wheels are 'free-rolling', and are not in motion based on some tiny drive-train in the armature.

I am only arguing that a plane, in the same position on a treadmill (ie, not overtaking the treadmill) will never acheive lift no matter how fast the plane is going. Can you at least agree with that part? that no forward motion = no lift?

Got ya. Cause the title of the thread says SITTING on a treadmill. 2 ways of interperting the question. The litteral nerd way, well of course a plane just sitting there won't take off. And the logical way, what I explained a few posts ago.

[spooky]

Originally Posted by TheAwkwardGuy

If the plane normally needs a distance of say 200 to take off on a normal runway, it would still need to cover the same distance measured from a fixed location if it was on the treadmill. The treadmill would not prevent the plane from moving forward but the plane's forward motion would cause it's wheels to spin faster than the speed of the treadmill.
Conventional planes need forward motion, not considering wind, to take off and to have forward motion there will always be a difference in speed between whatever is holding the plane up and the ground.

Not to nitpick here, but a plane only needs airspeed, not distance, not motion relative to the ground, to fly. A plane in ordinary weather conditions may typically need x amount of runway under y amount of force from it's engines to reach airspeed based on average load, just as you say, but you are adding in variables on a hypothetical equation that were never asked for, and only complicate things needlessly. It is a fact that, relative to the ground, a plane can fly backwards if the wind is blowing fast enough, the plane is light enough relative to wingspan and all the other complex physics that make planes properly fly(it's probably catastrophically dangerous). We could continue to add in a million other real life crucial variables, turbulence, temperature, air density, weight distribution, even materials it is constructed from, all very important in real life, but last I checked, planes don't run on treadmills anyway.

Micheal Scott always tells Dwight: KISS- Keep it simple, stupid!

[Saint Marcos]

Originally Posted by TheGrundle

Got ya. Cause the title of the thread says SITTING on a treadmill. 2 ways of interperting the question. The litteral nerd way, well of course a plane just sitting there won't take off. And the logical way, what I explained a few posts ago.

Well frankly, I don't mean sitting & not running. I simply mean that I can concieve of a treadmill that will keep the plane motionless -- In fact, unwittingly, the person on the video with the remote controlled airplane on the conveyor belt showed us, quite clearly, that he was able to keep the plane motionless by the conveyor belt (he simply, afterward, increased the thrust on the plane to make it overtake the treadmill and take-off).

What if that remote plane didn't have any more room left in the throttle? It would have sat on that treadmill, struggling to take off until the batteries ran down. Yet, it easily could have had enough juice to allow it to take off on a normal runway (we'll never really know the answer to that).

Since I see that a plane can indeed be made to hold still on a conveyor belt, the thrust behind it isn't what makes it take off. Its the point where it overcomes the treadmill & moves forward (creating lift) where it actually takes off.

[spooky]

Originally Posted by Saint Marcos

Well frankly, I don't mean sitting & not running. I simply mean that I can concieve of a treadmill that will keep the plane motionless -- In fact, unwittingly, the person on the video with the remote controlled airplane on the conveyor belt showed us, quite clearly, that he was able to keep the plane motionless by the conveyor belt (he simply, afterward, increased the thrust on the plane to make it overtake the treadmill and take-off).

What if that remote plane didn't have any more room left in the throttle? It would have sat on that treadmill, struggling to take off until the batteries ran down. Yet, it easily could have had enough juice to allow it to take off on a normal runway (we'll never really know the answer to that).

Since I see that a plane can indeed be made to hold still on a conveyor belt, the thrust behind it isn't what makes it take off. Its the point where it overcomes the treadmill & moves forward (creating lift) where it actually takes off.

straws. you are grasping at straws.

The lighter it is, the more of a factor friction becomes. Making the argument that the plane has only just enough power to just barely get off the ground under nominal conditions, and the treadmill being enough to tip the scale because of the fractional amount of resistance the wheels provide, assuming no air movement, etc, you are creating absurd variables and adding them into a simple equation, needlessly.

Go sleep well tonight, yes, it is a fact that a treadmill does impart some tiny amount of friction, in 99.9999999999999999% of all cases, it doesn't matter. Planes have engines powerful enough in real life to overcome infinitesimally minute variables, but in the case of your imaginary argument, it is possible that they may not. You may as well start throwing in gravity variables, as well, the higher the gravity, the more friction you will get in the wheel bearings.

/rolls eyes

[spooky]

Let me rephrase the question.

You are wearing roller skates, and I punch you in the face because you are a nerd and I am a bully. Hard enough that you are falling backwards, about to thump your head on the ground.

Is it possible, if you were on a treadmill, to prevent you from hitting the ground if(assuming the two back wheels on your 80s retro 4 wheel hipster skates that you say you are wearing ironically never lose contact with the ground), at the last possible instant you just make the treadmill suddenly accelerate fast enough?

Or is the friction in those wheels just way way WAY too inconsequential to have any place in the equation of you getting beat the fuck up, on a treadmill, you contrary nerd fuck?

[Incognito]

Haha, great example spooky.

[Saint Marcos]

Originally Posted by spooky

straws. you are grasping at straws.

The lighter it is, the more of a factor friction becomes. Making the argument that the plane has only just enough power to just barely get off the ground under nominal conditions, and the treadmill being enough to tip the scale because of the fractional amount of resistance the wheels provide, assuming no air movement, etc, you are creating absurd variables and adding them into a simple equation, needlessly.

Go sleep well tonight, yes, it is a fact that a treadmill does impart some tiny amount of friction, in 99.9999999999999999% of all cases, it doesn't matter. Planes have engines powerful enough in real life to overcome infinitesimally minute variables, but in the case of your imaginary argument, it is possible that they may not. You may as well start throwing in gravity variables, as well, the higher the gravity, the more friction you will get in the wheel bearings.

/rolls eyes

Agreed. The only part I take exception to is your poking at me because I've personally conceived of an "imaginary argument"......as if my imaginary argument is somehow interfering with your larger, concrete discussion about airplanes on runway-sized treadmills. (That goes for Grundle, as well.)

[spooky]

I'm just keeping things polarized, this is an immensely entertaining thread.

That said, at least we can all come together, regardless on how we voted, and agree that roughly half the voting population in the forums is completely retarded. Right? We do all recognize that half are wrong, stunningly so, lose faith in humanity so. Regardless of how you voted, stats in the news that make absurd statistical claims about the relative stupidity of Americans makes sense, all of the sudden, to all of us, regardless of your vote.

We are unified in that sense.

right?

[dzagama]

On a more interesting note: Pendulum Fallacy

And you can masturbate to this: