https://twitter.com/engineers_feed/s...848378368?s=21
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My gut says no so it’s probably yes, but I wouldn’t begin to know why it could of couldn’t.
Didn't Mythbusters do this? and the plane can take off? I can't remember
I believe the answer is yes.
The plane actually has the same forward momentum required to take off, it's just not going anywhere.
A good way to think about this is if you suddenly stopped the conveyor belt and the plane engine simultaneously, the plane would lunge forward from its existing momentum.
Yes
The conveyer belt matches (cancels) the wheels forward motion.
The plane only achieves forward motion when the jet engines pull it thru the air.
Air movement past the wings means lift.
The pilot just got notice he is being laid off.
So we are just building these long runways when we can just install conveyor belts? We have enough land. Sounds like a job for Japan.
we should just use catapults like aircraft carriers do.
No!
not googling it but i guess no because wind
also, earth is flat
this might be the most pfa thread in history.
air passing over and under the wings generates lift, you absolute start spangled retards.
none of you could have possibly graduated high school in an actual first world country.
Dude, I’ve actually taken flying lessons, and got to do a few solo flights before I gave it up after passing out during a spin recovery. And you know what my trainer said during my first lesson after asking me “What makes a plane fly”, to which I had responded with some technical answer? He said “Money. Lots of it. Now where’s your check for this lesson?”
And seeing as I don’t see any money coming off that conveyor belt, my answer to the OP’s question is “Hell, no!”
no, for the reason Sont mentioned...specifically the lift needed to get the plane off the ground is caused by air moving over the wing at a faster rate than air moving below the wing...that creates lower pressure above the wing, greater pressure below, and thus the plane is lifted---the engines merely create the air flow over the wings, but because in this instance the plane is not moving forward, there is no air flow...the shape of the top part of the wing (arched with trailing edge extended) helps create lower air pressure over the wing as air passes over it--the Wright brothers discovered this by studying the shape of bird wings & building the first air tunnel to find optimal wing shape
interesting, but the experiment does not match the problem stated imo....in the experiment the plane used has its propeller is in front of the leading edge of wing, thus creating airflow over the wing despite no forward movement....
also, a car is towing the takeoff strip, thus both the plane and the strip are moving, hence airflow...the problem has the plane on a stationary treadmill where it remains in one position at equalibrium
the 747 engines are below and behind...i don't think the intake of the jet engines would create enough airflow across the leading edge of the 747's wing...not enough to air flow to lift the plane...indeed air into the front of the engine could cause some reverse flow over the top of the wing
this is probably the best explanation of the problem that I've read.
https://blog.xkcd.com/2008/09/09/the...amn-treadmill/
thanks for finding this...
i don't mean to be stubborn but:
well, the explanation to my mind does not fit the problem...the problem states that the conveyor offsets the forward thrust of the engines, such that plane says is the same position, thus no airflow
the explanation claims forward movement will result because the engine thrust is so powerful it overcomes the offsetting force of conveyor against wheels, such that the plane moves forward, airflow results and lift occurs...i believe that is what would occur in a real life test, but the problem stated (i believe) that the plane stays in the same location despite the engine thrust
okay, i done, this fish is finished.
You can be stubborn, but you shouldn't re-word the problem. The problem states "The conveyor belt is designed to exactly match the speed of the wheels, moving in the opposite direction." It does NOT offset the forward thrust of the engines, that's the point. It can negate it to a certain amount of thrust, but after that, the plane's gonna go regardless of what its wheels are doing. That's how I understand it, anyway.