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100_Percent_Juice · 2008-01-30, 08:21 PM

Mythbusters did this...
Find the speed needed for the airplane to take off.
Set the treadmill to that speed in the opposite direction.
Will the airplane take off?

Lets say the take off speed of the airplane is 20mph.
Since the wheels are not powered, it doesn't matter if they are sitting at 0mph or spinning at 100mph, once the prop starts thrust, its going to move the plane forward at the 20mph takeoff speed. Which the airplane took flight in every one of their experiments. I feel this is different then the question that we have been debating. Which I agree the question posted online is flawed.

"Imagine a plane is sat on the beginning of a massive conveyor belt/travelator type arrangement, as wide and as long as a runway, and intends to take off. The conveyer belt is designed to exactly match the speed of the wheels at any given time, moving in the opposite direction of rotation.
There is no wind.
Can the plane take off?"

This is where the questions differ. Mythbusters set the conveyor for the takeoff speed on the airplane, they did not set the conveyor to match the speed of the wheels at any given time. So of course the plane did not stay in the same place, enabling it to then reach takeoff speed.

IF there was a MAGICAL conveyor that could speed up to infinite MPH and match the wheel mph keeping the airplane in the same place, then the airplane would not take off. That is why the question online is flawed and could never be proven in a real life application because the airplane would match the conveyor speed and add the takeoff speed causing the conveyor to speed up eventually causing the airplane to look like JC's evo.

2008-01-30, 08:21 PM	#122
100_Percent_Juice (40 percent vodka) Real Name: Joel Join Date: Oct 2006 Location: Reno, NV Posts: 4,446 Car: 2004WRX Class: Baby-Hauler/GroceryGetter	Mythbusters did this... Find the speed needed for the airplane to take off. Set the treadmill to that speed in the opposite direction. Will the airplane take off? Lets say the take off speed of the airplane is 20mph. Since the wheels are not powered, it doesn't matter if they are sitting at 0mph or spinning at 100mph, once the prop starts thrust, its going to move the plane forward at the 20mph takeoff speed. Which the airplane took flight in every one of their experiments. I feel this is different then the question that we have been debating. Which I agree the question posted online is flawed. "Imagine a plane is sat on the beginning of a massive conveyor belt/travelator type arrangement, as wide and as long as a runway, and intends to take off. The conveyer belt is designed to exactly match the speed of the wheels at any given time, moving in the opposite direction of rotation. There is no wind. Can the plane take off?" This is where the questions differ. Mythbusters set the conveyor for the takeoff speed on the airplane, they did not set the conveyor to match the speed of the wheels at any given time. So of course the plane did not stay in the same place, enabling it to then reach takeoff speed. IF there was a MAGICAL conveyor that could speed up to infinite MPH and match the wheel mph keeping the airplane in the same place, then the airplane would not take off. That is why the question online is flawed and could never be proven in a real life application because the airplane would match the conveyor speed and add the takeoff speed causing the conveyor to speed up eventually causing the airplane to look like JC's evo. __________________ "A power nap is when you sleep on someone who is weaker than you." - Dimitri Martin Last edited by 100_Percent_Juice; 2008-01-30 at 08:23 PM.