haha, fess up. who rang dr karl about this! 7mins in http://www.abc.net.au/science/podcast/triplej/drkarl_20070426.mp3
http://www.abc.net.au/science/k2/stn/default.htm

Question: James wants to know if a plane was on a treadmiill going in the opposite direction, would it be able to take off?

Karl: The latest issue of the Smithsonian's journal Sky and Space covers this. If you put your hand out the car window while you're driving, your hand rises up - the only thing that matters for lift is speed of air over the wings. A normal jumbo take off would have 80 m2 of wing area, and the air flowing over the top of the wing is so fast it's at lower pressure ( 5 tonnes/square metre), so there's 5 x 80 tonnes worth of lift - which is enough lift to raise the plane. If you had a plane just sitting on the runway and you had fans powerful enough to make air move over the top of the wing really quickly, it would lift. So it's all about the air over the wing.

kekeke ^_^



First post in an epic thread :P

last edited by Cl1nt at 18:47:47 26/Apr/07

He didn't answer the question.

And it wasn't you clit.

If the treadmill matches the speed of the wheels on the plane it wont take off, if it matches the speed of the plane it will take off. lol!

Props for whoever had the audacity to ask that question :)

And it wasn't you clit.

Never Implied it was, because of course, my name is James..

IT WAS LOKI, CAUSE LOKI IS JAMES!!!

If the treadmill matches the speed of the wheels on the plane it wont take off, if it matches the speed of the plane it will take off. lol!

r_mazing loses :(

I knew this would be useful again one day
http://users.bigpond.net.au/ritsuko/emoticons/plane-treadmill.gif

Um. Putting your hand out the car window isn't the same. The car is moving - the treadmill isn't. Isn't that obvious? How can there be wing speed over the wings if the plane is sitting in the same spot all the time. It's the same as putting a plane on a dyno - it's just the wheels spinning.

Oh dear :(

Um. Putting your hand out the car window isn't the same. The car is moving - the treadmill isn't. Isn't that obvious? How can there be wing speed over the wings if the plane is sitting in the same spot all the time. It's the same as putting a plane on a dyno - it's just the wheels spinning.

MORON ALERT

JET POWERED LOL.

Posting in what is soon to become an epic thread of stupidity.

Question: James wants to know if a plane was on a treadmiill going in the opposite direction

Hangon, is the treadmill rolling, moving or both rolling and moving in the opposite direction?

The plot thickens!

oh god, not again

What does a car gets it's power from? It's wheels, which are touching the hypothetical treadmill so that is why a car stands still on a dyno.

Where does a plane get it's power from? The turbines/props on it's wings, which aren't touching the treadmill. The wheels are simply free spinning inconsequently while the plane moves on forward.

So really, wouldn't the plane fall backwords?


/adds to the stupidity.

If this thread makes it past 2 page we should all kill ourselves

haha stez

mat damon

I knew this would be useful again one day

hahah, on QGL that's useful every day!

This thread is hilarious already.

no way

The car is moving - the treadmill isn't. Isn't that obvious? How can there be wing speed over the wings if the plane is sitting in the same spot all the time.

I agree, the position relative to the air around the wings is not changing, thus lift cannot be generated.

Think about what would happen if you stood on the ground with a shopping trolley on a treadmill in this situation. Can you push the shopping trolley forward or not?

can you?

Oh s***, get the f*** out of here! What are you doing? Go, get the f*** out of here, you stupid idiots! f***, we're all dead! Get the f*** out!

i think this is a job for mythbusters. first they should try it on a model airplane. then use the real thing. if the plane doesnt take off they can always blow it up.

Oh s***, get the f*** out of here! What are you doing? Go, get the f*** out of here, you stupid idiots! f***, we're all dead! Get the f*** out!

At least post the video of it!

Prime forum real estate for sale.
Prime positioning in the second page of an epic thread.
Walking distance from the original poster.
Good investment.


Mad props to the guy who called that in. Hillarious.

I laughed so hard when I heard this on the radio this morning, I've been waiting for the thread since. I can't believe I didn't get here in time to make it on the front page.

My only complaint with the question was the incorrect use of internet terminology. So whoever rang up can't been that intelligent or internet worthy. A thread is what it's call buddy. Threads are inside forums.

Where does a plane get it's power from? The turbines/props on it's wings, which aren't touching the treadmill. The wheels are simply free spinning inconsequently while the plane moves on forward.

Um no. The plane moving forward is different to lift. If the plane had its turbines on full on a treadmill, and the treadmill suddenly stopped, the plane would shoot forward and most likely crash - it wouldn't take off on the spot. Lift can only be generated by the plane passing through air. Clearly if the plane is going nowhere then there's no air flowing under the wings.

How on earth is that possible when the wheels are completely free to rotate?

I didn't understand it either, so I read the long long long arguments already on the internet. Part of understanding it is reading the question as it was originally posted... from there, there are a couple of really simple answers.

Well I'm assuming that if a jet had its turbines on full, and suddenly went from a stationary position to free-moving, it would be like a slingshot and extremely hard to control...either way its either gonna move forward along the ground until there's enough lift to take off, or its gonna crash. Irrelevant though, because the question is whether it can take off while it's on the treadmill.

It moves forward on the treadmill relative to the ground:O

http://graphics8.nytimes.com/images/2006/12/11/technology/poguespan.jpg

Unless its a jetstar plane and it would just get stranded on the treadmill regardless.

last edited by 3x0dus at 23:18:45 26/Apr/07

I think I'll switch my door choice so I can win the goat!

is anyone actually taking this thread serious?

I sure hope Le Cock isn't because otherwise he is really that dumb.

haha

nF: Planes on a treadmill, not nerds.