[Science Question] Will a plane take off?

lol its simple, it definately, most positively.... would NOT work. theres no lift being generated by the wings. without lift planes are just buses with useless peices of metal hanging out the side

ok lets split this into 2 categories and tell me if you agree/disagree with both - then I can construct my arguements accordingly:

1.

If the plane and belt are moving at the same speed, the force of the engines thrust will propel the plane forward... As unlike a car which is propelled forward by friction a plane moves through air pressure and prop lift, so the only difference between using a belt and a runway would be that energy is consumed through friction and rotational kinetic energy... however this slight resistance wouldn't be enough to stop the plane from propelling itself forward.

2.

I retarct the statements I made prior, I now think that if the wheels are matching the speed of the conveyor belt it will not take off, my initial logic was that the wheels on a plane act like the cushion of a hovercraft - they are there to reduce friction.... However if you use a big enough force to propel the vessel forward then it will over come the friction... This works great till I applied it to our aircraft, an aircraft traveling at 40mph will need wheels traveling 80mph to match a belt moving 40mph, so if the wheels match the planes wheels it would actually move backwards?

I'll eat humble pie

however if the plane is matching the belts speed it will take off.

this debate seems to be going on forever like which came first the chicken or the egg???

chicken

that doesn't make sense?!

if the belt is matching the thrust produced by the enginges then the plane will NOT take off as there is not enough lift being generated by the wing due to insufficient airflow.


if the plane is staying in the same place then theres no lift so no takeoff

Joe> I have just written a big long reply in a word doc (to save spending work time connected to the net), and have closed the doc without copying and pasting, and can't be btohered to retype it. Just so you know, i partially agree with both your points.

how annoying is it when that happens!

If our jet is moving at 40mph in one direction and the conveyor is moving 40mph in the other, then our jet will still go forwards at 40mph, but the wheels will rotate at 80mph.

If this were a car then it would be different as the car would be pushing on the conveyor belt, however this isn't a car - its a plane and its pushing against the air.

surely the plane stays still and its just the wheels moving!?

no.

but the conveyor belt is supposed to be going at the same speed as the wheels
the wheels cant go at 80 and the belt at 40

:spangled:


ps. i havent read this from the start and really dont intend to.

thats not the point though, the plane would not be moving as in Colins initial question the planes wheels would be matching the speed to the conveyor, therefore the plane would stay in the same place and the only movement would come from the wheels.

If you'd read through the thread you'd realise two question were asked (or one was misread by me ).

the intial question asked on one messageboard was different to the question colin asked. The initial question was that the plane was moving the same speed as the belt.

So this big shit thread could have been avoided if Colin had just asked the right question ?

Top work Col

well in response to Colins first question the answer would be no the plane cannot take off. never saw anyother questions as i missed out loads of this thread

There's an atmosphere of intellectual scientific discussion this afternoon.

If the belt's moving backwards against the forward speed of the plane the only effect that will have is to make the wheels rotate twice as fast as they would have done. The acceleration/speed of the plane is ALL to do with the thrust of the jets so it would be going just as fast as it would have done

say the plane gets up to 100mph, the belt's going backwards at 100mph, effective wheel speed is 200mph which doesn't matter a toss as that's got nothing to do with anything, so the plane will take off as normal, I bet my house on it