The ultralight had forward speed -- he was passing the traffic cones. if the plane stayed true to the original intent of the problem, (something like "plane/conveyor equal & opposite speeds), stationary relative to an outside observer / airspeed, the pilot is right, it goes nowhere but off the end of the 2000ft tarp.
The plane was supposed to stay stationary if the conveyer belt was matching the speed the plane was going.
First, it is about keeping a plane and a conveyor belt at constant speeds in order to achieve a ground speed of zero. In other words, if Jamie's truck is driving 20 mph to my left dragging a huge tarp, and a plane on that tarp is going 20 mph relative to the tarp towards the right, to me, the plane is just sitting there. On a calm day, this achieves zero air speed. Aerodynamic lift is about air moving over foils. It is not related to thrust (ask a hangglider) or forward velocity of the entire craft (ask a helicopter pilot), it is only about fluid movement over foils creating a pressure differential. If a plane has zero air speed, no lift will be created.
Of course the plane took off, even though the belt was moving in the opposite direction the plane was still moving forward. I would bet anything that if you too the trucks speed at take off and subtracted the planes instrumental speed at take off the difference would be greater than the planes required take off speed.
The whole premise of the myth was that the plane remained stationary, which it clearly didn’t. The myth is not busted, your method is busted.
They need to go over this again and make sure that the airplane is stationary.
I agree with you. The myth doesn't seem busted because the plane way actually moving faster than the belt.
On the show the airplane was going faster the the treadmill
I think that was totally inaccurate. the plane was moving on the ground forward faster than the conveyor belt. They werent traveling at the same speed. If the belt would have been moving faster then it would have been more interesting. That test was way too fast.
The plane is supposed to be going the same "speed" as the conveyor belt, except in the opposite direction, but unless you say what the speeds are relative to, it's meaningless.
If you decide the belt's speed is defined relative to the ground, and the plane's speed relative to the belt (when the speed that matters in flight is plane relative to air), you get a plane that stands still relative to the air and thus it doesn't fly. Perhaps there's something psychological going on that tricks so many people into thinking about it in that convoluted way. In the episode they measure the belt's speed relative to the ground (truck speedometer) and the plane's relative to the air (as is normal in aviation) in conditions where airspeed and groundspeed are equivalent (no wind), and they obviously get flight.
The point to this myth was to see if an airplane could take off from standing still.
I'm here to represent a discussion coming from a foreign forum with about 16 thousand views and 1 thousand posts...and everybody is saying that the test was totally invalid and with no proven scientific results. Jamie and Adam, you blew it.
The myth is that the plane and belt are going the same speed, except it isn't a myth, it's just a misunderstanding.
The whole point is that airplanes fly only in relation to 'relative wind', which is the speed of the air moving over the wings. The conveyor belt, wheels and propeller have zip to do with it. The only reason the airplane flew is because it was moving relative to the air around it. The only way it could fly and remain stationary is if there was a large fan capable of consistently producing enough wind over the leading edge of the wings to sustain flight., and the propeller was producing enough thrust to hold it stationary or accelerate.