It is difficult to imagine how anyone could actually believe that a plane on a treadmill could take off. Then again my elementary school library had books on the fundamentals of flight and concepts such as thrust, drag, lift and gravity were ingrained in my mind at a very, very young age.

I want to see the footage because I imagine the pilot of the Piper Cub had a handful just trying to keep it on the treadmill (IOW, keeping it from turning and rolling off one side or the other).

On the other hand... if you want to see a plane take off from a fixed point and appear to hover above it, take a plane with a low stall speed (a J-3 Cub would be a good candidate) and place it on the deck of an aircraft carrier going full-on into a stiff wind. The wind ends up being the "treadmill" (and the "fixed" point of reference is actually moving).

If you genuinely believe that a plane would take off from a treadmill with no airspeed (no air velocity over the wings to produce aerodynamic lift), ask yourself why aircraft carriers have catapults, why Sikorsky developed an operational rotary-winged aircraft (that's a helicopter folks... you know... the one that DOES take off vertically because the wings are spinning overhead), and why planes like the Harrier and the F-35 (the B variant if I recall correctly) direct their jet thrust directly down in order to achieve vertical lift.

titantv.com also listed this episode as having the experiment that we didn't see.

quote:

If you genuinely believe that a plane would take off from a treadmill with no airspeed (no air velocity over the wings to produce aerodynamic lift)

I think almost no one believes that. Watch the show when it comes out and watch the airplane fly.

Ya! What he said!

Just think of a bottle-rocket lying on a treadmill. It'll zip along no matter what that treadmill is doing. Just imagine a thrust-driven vehicle with wheels now! No doubt it'll advance forward and take flight -- should the conveyor be long enough.

quote:

It is difficult to imagine how anyone could actually believe that a plane on a treadmill could take off.

http://community.discovery.com/eve/forums/a/tpc/f/9551919888/m/2211983939/p/1

Happy reading.

There are more posts than that one, and someone of them go into the real physics.

quote:

Originally posted by typical_is_back_again:
Ming, got a little something for you.

Shut your mouth and wait for the show to come out before you start complaining.

.
Pique noted.
BTW, the plane has to fly.

quote:

Originally posted by christi7df:

quote:

If you genuinely believe that a plane would take off from a treadmill with no airspeed (no air velocity over the wings to produce aerodynamic lift)

I think almost no one believes that. Watch the show when it comes out and watch the airplane fly.

Are you suggesting that everyone with knowledge of the principals of aerodynamic flight who are asserting that ground-speed without air-speed does not equal aerodynamic lift are wrong?

I know there are some big words (and even bigger concepts) in my post but, do you actually understand what I am saying, or are you just sticking your fingers in your ears, closing your eyes, and praying that Jesus will come lift the airplane off the ground and prove you correct? No one can support their argument that the plane will fly because there is no realm of physics in which to find such support.

If you want to know about flight, listen to those who actually know how to fly and why they can.

Here's another thought experiment:
If you can take off from a treadmill, surely you can land on one right? If a plane could hover over a treadmill and touchdown, why even have the wheels and the treadmill in the first place? Why not just have legs and set down on a concrete pad?

Whats that you say? The plane would come in normally but once it hit the treadmill it would cease all forward momentum because the wheels are on the treadmill? This, in effect, is the same thing the Mythbusters investigated in the knight rider myth where they drove the car into and out of a moving tractor-trailer rig. If you'll recall, the car did NOT crash into the front of the trailer.

It's simple physics. A plane cannot fly without airspeed. Period. Every pilot knows that once you drop below a certain airspeed the wings stall. "Stall" is another way of saying "stop flying". IOW, drop like a stone.

Ok, since people are insistant on diving off the topic of THIS particular thread, it's getting locked. Take your discussion to the thread in Transportation about this show idea.

MythMod