B Can a 747 Take Off on a Conveyor Belt?

[boneh3ad]

I can't believe this is still under discussion.

It doesn't matter what the wheels are doing - it's not a car.
A plane gets its forward motion via the air, using props or jets.
Once the thrust of the engines rises, the plane will accelerate with respect to the air - and eventually gain lift via air, as usual - no matter what the wheels are doing.

You can do whatever you want with the conveyor - move it as fast as you want - till the wheels blow, and the landing gear is worn down to nubs - the plane is still going to move forward, given sufficient thrust.

Full stop.

To clarify, it would matter slightly if only because the faster the wheels are turning, the more rolling friction the plane would likely experience, but this would only affect the rate at which the plane accelerates and would be very small compared to the overall thrust. I'd imagine that the wheels would simply catch fire and melt long before they moved fast enough to provide enough frictional force to stop the plane moving forward.

So yes, I fully agree (as I stated like 5 pages ago) that the rotation of the wheels is largely irrelevant because the engines, and therefore the forward force, really don't care what the wheels are doing. They only care about the air.

I feel like this thread has jumped the shark.

 

[OCR]

Lol... all in fun...

Now...
Carry on.

[Edit to add a final clarification:]

"If you’re desperate to tell me that I’m wrong on the internet, don’t bother.

I’ve snuck onto the plane into first class with the #5 crowd and we’re busy finding out how many cocktails they’ll serve while we’re waiting for the treadmill to start.

God help us if, after the fourth round of drinks, someone brings up the two envelopes paradox." <sup>[1]

1</sup>[Source attribution]


Oh, and BTW... has anybody looked here ? ...

[End of edit to add a final clarification:]

Now...
Carry on.

 

[Nidum]

+25

Yes - it's that simple .

 

[A.T.]

...till the wheels blow, and the landing gear is worn down to nubs - the plane is still going to move forward, given sufficient thrust.

But... but... with a landing gear worn down to nubs, will the thrust be sufficient to reach take off speed within the length of a normal runway?

 

[sophiecentaur]

I can't believe this is still under discussion.

Yes you CAN! This is PF

 

[sophiecentaur]

But... but... with a landing gear worn down to nubs, will the thrust be sufficient to reach take off speed within the length of a normal runway?

Then we no longer have wheels and the question no longer applies.

 

[DaveC426913]

Oh, and BTW... has anybody looked here ?

Oh my stars & garters - XKCD has a forum??
Where have you been all my life?

 

[berkeman]

Oh, and BTW... has anybody looked here ? ...

And with that, I think we can call this thread done. Thanks for helping out, folks.