THE PLANE TOOK OFF

[WildBillyT]

Originally Posted by JL8Jeff

They didn't replicate the myth properly though. They accelerated the plane suddenly and the myth said it was moving the same speed as the conveyor. So a conveyor moving 25 mph and a plane moving 25mph will not take off at 25 mph!

But if the plane is traveling at 88mph it should take off through time to help Marty protect Doc Brown from a Libyan assasination.

[ar0ck]

Originally Posted by WildBillyT

But if the plane is traveling at 88mph it should take off through time to help Marty protect Doc Brown from a Libyan assasination.

Next time don't tell people your going to build them a bomb, and you won't have that problem. Or just wait for a Mr. Fusion.

[Knipps]

On again, NOW on discovery channel

[jims69camaro]

the part i get stuck on is that the original problem states that the conveyor moves at the speed of the wheels. since the wheels are only holding the plane up while it accelerates to the speed necessary to take off, and there is no power being applied to the wheels like a car, then why would the conveyor be moving at all?

if, instead, we assume that the conveyor would move at the speed of the plane as it accelerates towards take off speed, then that's different, and i don't see the plane generating enough lift to take off. being on the discovery channel has nothing to do with it, they can be wrong just as any of us could. and a sudden burst of speed would only accelerate the conveyor, so it would balance itself out and not take off.

[Knipps]

the air still moves under/over the wings, generating lift & the plane takes off.

[jims69camaro]

how does the air move under/over the wings if the plane is not moving? it's stationary, because the wheels are moving at the speed of the conveyor... the plane doesn't move forward because the wheels are on the conveyor, which is matching any speed relayed to the wheels (which i assume to be zero), but even if some speed where relayed to the wheels it would be negated by the conveyor moving at the speed of the wheels.

[GP99GT]

dude....give up

you just dont get it

[98tadriver]

Originally Posted by Jersey_TA

Beat me to it.

likewise!

[jims69camaro]

Originally Posted by GP99GT

dude....give up

you just dont get it

well, it would seem that you have a thorough understanding - so, please, enlighten me.

[69BirdX]

i got an rc plane.......some one provide the tread mill we can do it in my back yard

[GP99GT]

Originally Posted by jims69camaro

well, it would seem that you have a thorough understanding - so, please, enlighten me.

i enlightened everyone a thousand times over in the original thread...and mythbusters did also

[1972LT1]

Originally Posted by jims69camaro

how does the air move under/over the wings if the plane is not moving? it's stationary, because the wheels are moving at the speed of the conveyor... the plane doesn't move forward because the wheels are on the conveyor, which is matching any speed relayed to the wheels (which i assume to be zero), but even if some speed where relayed to the wheels it would be negated by the conveyor moving at the speed of the wheels.

I'm with you brother...I've tried to explain this on other boards too . No one seems to understand that the conveyor is moving backward at the same speed that the wheels are moving forward. So if the plane is not moving forward, there is no air over the wing and therefore no lift.

[Knipps]

yes because the propellers are just thrown on there, there's no science to them at all.. they don't cause any movement of air

[GP99GT]

watch the mythbusters episode and youll understand it....and if you still dont get it....then im sorry

[jims69camaro]

Originally Posted by GP99GT

watch the mythbusters episode and youll understand it....and if you still dont get it....then im sorry

i'll look for that.

btw, i gave you an opportunity to say/do something positive. fail.

[firehawk1120]

i agree with the people argueing that it should NOT take off. The problem I have with the mythbusters show is the tarp that they put under the plane allows the wheels to maintain contact with the ground and allowing the plane to travel at a different speed then the tarp.

If you are on a treadmill running at 1 mph do you go anywhere??? NO. BUT, if you are on the treadmill and it's going at 1 mph and you start running faster what happens you run into the bar in front of you until you slow down. SO, if the ground was actually moving at the same speed as the plane trying to move forward the plane should remain stationary, IT DIDN'T it was moving forward proving the speed of the plane was greater then that of the tarp being pulled by the car.

In conclusion those people are doing an incorrect test and should know better.

[GP99GT]

you'd all be right if the plane was driven through its wheels, like a car, or like a persons legs on the treadmill

but since the planes engines are pushing off the air, not the ground, whats underneath it has little to no effect on takeoff (so long as its flat ground of course)

[V]

wheel speed is irrelevant. As the propellers PULL the plane forward(that kinda what propellers do), the plane will move forward in "space". yes wheels will accelerate forward and tread mill will then move backwards cancelling "wheelspeed" however plane will STILL be pulled forward because movement action is based on the air, not ground. The wheels and tread mill will obviously increase in speed too BUT that wheelspeed will increase rapidly and exponentionally. All in all the tread mill would need to be the length of a runway, it would just be spinning the wheels at an incredible rate of speed until the plane has enough lift to break contact with the ground.

[sweetbmxrider]

the plane has no relation to the ground. its how they work. saying that the plane is still contacting the ground through the tarp has no affect on the plane. i would give the example of removing a dinner table cloth from under a set table....but i feel it will stir up more controversy.

the propeller is pushing/pulling the air in front of it. that is where the force is being applied. even though the plane isn't moving in relation to the ground, its moving in relation to the tarp. the tarp is moving in relation to the ground. i dono. if you over think the subject, you will get frustrated.

Edit: Oh that is a much better explanation SmokingSS. if you read mine, you will probably become dumber...

[Savage_Messiah]

**** THE PLANE

[V]

Originally Posted by Savage_Messiah

DE PLANE BOSS, DE PLANE

fixed

[firehawk1120]

I'd like to see a plane suspended from the ground dropped like missle from a fighter jet and see if the thing automatically started going forward or if it dropped straight down first then that would prove you don't need to be moving to take off.

If the wheels don't need to move to take off then why do planes need runways shouldn't they be able to just launch from a standing position????

Still say it's not possible if the planes not in motion to take off.

[GP99GT]

the plane IS in motion! holy ****

its not just taking off from a standstill...you guys fail

im done with this thread, watch the show, youll understand

[Knipps]

Originally Posted by firehawk1120

I'd like to see a plane suspended from the ground dropped like missle from a fighter jet and see if the thing automatically started going forward or if it dropped straight down first then that would prove you don't need to be moving to take off.

If the wheels don't need to move to take off then why do planes need runways shouldn't they be able to just launch from a standing position????

Still say it's not possible if the planes not in motion to take off.

friction. it's a lot easier to roll than to get the plane to speed standing still.
you can't just get in a car and do 60. it takes acceleration

[sweetbmxrider]

you need runways to land...