@plot-paris said:

but you are refering to the first question now, don't you? where the conveyor adopts the speed of the aircraft, therefore is not able to stop it.

but if the conveyor has a sensor that detects the movement of the plane. if the plane moves forward, the conveyor will accelerate until the plane doen't move forward anymore.
that would eventually (at a very high speed of the conveyor) keep the plane from moving relatively to it's surroundings.

to completely solve the mystery we have to set up a formula with all important variables, like:

weight of the plane

frictional resistance of the wheels

conveyor speed

subjective plane speed

objective plane speed

we need someone to calculate how much energy is lost due to frictional resistance. then we need to know how fast the plane has to be to take off. then we can calculate how fast the conveyor has to be to stop the plane from moving forward...

no no no no no

the converyor belt would never fully compensate for the planes thrust, remember the wheels are free-wheeling, like stated before all it would do is make the wheels spin even faster.

look at it this way, could a converyor belt travelling in the opposite direction to a landing plane stop it's movement? no.

pav

@chris fullmer said:

I fail to see how this is a different question? We've established that the conveyor belt can move however fast it wants. The rotational speed of the wheels has nothing to do with the plane moving forward, as long as the brakes aren't on and there's nothing physically holding the plane to the ground.

So the plane still takes off.

Chris

i agree

pav

@plot-paris said:

ok. we agree with the fact that the plane, if it's engines are turned off and the conveyor is moving, will be transported backwards, right?

so if the plane accelerates and tries to move forward, the conveyor accelerates likewise. wo we have a forward-motion of the plane and a backward-motion of the conveyor, which results in the plane being stationary compared to the people standing arround the whole machinery.
this is exactly like pav running on his treadmill. no matter how fast he runs, the treadmill is always keeping him in the same place.

we know the plane can only be lifted up by air pressing aginst it's wing (because that is how planes fly).

we also know, that the plane stays stationary in relation to the spectators around (otherwise the conveyor would have failed it's purpose and the whole experiment would have gone wrong).
and because the air arround the spectators is stationary (unless there is a fierce wind due to weather), it does not move in respect to the plane (except the air, that is sucked in and blown out by the jet enginge of course. but that does not pass by the wings of the plane).

regarding these facts we have prove that there is no upwards thrust of the plane's wings by air.

and that means, that the plane is not able to fly

you're wrong

pav

David_H : exceptionally funny!

Modelhead : exceptionally concise!

pav

@plot-paris said:

to make it more clearly, take pav's idea of attatching wings to your arms and running on a treadmill. you can run as fast as you can, you will most certainly not be able to take off.
if you now jump from the treadmill to the side on the ground, you will discover, that your relative speed to your surroundings (and therefore to the air surrounding you) was zero!

hold on a sec, i added an edit to my post, i believe that the plane WILL take off.
running on a treadmill is very different as the propulsion is from the legs.
the propulsion for the plane is not from the wheels, but the jet, or prop.

the air would pass over and under the wings and create lift, all that the conveyor belt does is negate the planes forward movement realtive to the ground, which makes no difference anyway. you need to look at the planes movement relative to the air around it.

the plane will attain lift.

pav

the one with the dollar bill had me in stitches.

almost worth moving to america so i can do that to every dollar note i come across.

brilliant.

cheers solo

pav

just had a full blown office argument about this, for about an hour on an off, (and this is no exageration).

only one other person in my office agreed with me on the plane being able to fly, and together, we had to convince the other 6 in the office they were wrong.

not an easy task, but one i enjoyed none the less.
at one point, someone went to their car and got out a toy car ( i presume their kid left it in there!) and did a demonstration as to why it would not work.

after it was pointed out to him that a cars propulsion was very different from a planes he totally understood. and also cherried up like i have never seen before, it was hilarious!

thanks remus, hours of fun!

pav

i stand corrected!

personally i can't think of when i'd use it, but i'm sure i wouldn't be without it if i had it!

pav

yeah i can see how this could be useful, isn't it essentially the same as the bezier edge thingy?

sorry for the lack of detail, i'm exceptionally tired.

pav

no way is that bad boy taking off.
i'll try it at the gym tomorrow, i'll attach some wings to my sides and jump on the treadmill.

if this did work, airports would be a hell of a lot smaller. he he

pav

[EDIT] Just walked into my kitchen about 6 meters away. poured a glass of milk, and walked back to the computer, and my A level Physics kicked in, and i realised what a fool i had been.

the plane does of course take off.

feel like such a fool, thank god for the EDIT function eh!

well said

pav

twilight zone...i was just about to request an anglepoise lamp and a decent low-poly bed.

thank you so much solo, generous yet again!

pav

wow, these are awesome!

cheers guys

pav

oh...

he he

pav

lewis, i understand your point, (johnsenior i don't really get yours, but i am a bit of a numbscull!)

hmm, it is a puzzler, seems like one descision couldn't be made so they just made all of them!

pav

off to france on a bicycle made for two?

i want to see images of this home made tandem of "questionable durability" pics please!

oh and good luck!

nutter. lol

pav

awesome work remus, very nice indeed.

pav

he he, i'm such a wind up.

there is a simple solution to having that granite bike saddle.

ride standing up. ha ha

pav

@unknownuser said:

Off Topic, Pav, why do you quote the previous post? All it does is add more lines thus more scrolling. I see a number of people doing it and it makes no sense. I can understand if one is responding to a few posts above but not directly after a post.

because i like the grey box around it. ha ha.

i hadn't noticed that it was the next post, i'm ususally not such a pain in the arse, i'll try not to be in future. he he.

pav

@unknownuser said:

:roflmao:

I was thinking that this would make a nice seat.
http://www.sketchucation.com/forums/scf/viewtopic.php?p=78324#p78324

no comment

pav