tommu56
Elite Member
Re: Mythbusters/airplane/treadmill
All right who's watching?
tom
All right who's watching?
tom
will it take off?
- Thread starter schmism
- Start date
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MrJimi
Elite Member, Rest in Peace
Re: Mythbusters/airplane/treadmill
No Discovery here
No Discovery here
tommu56
Elite Member
Re: Mythbusters/airplane/treadmill
For the record Mith Busted as they say on TV!
The model plane took off from the conveyor belt.
The pilot of the ultra light thought he woulden't take off.
When they tested it the plane took off.
tom
For the record Mith Busted as they say on TV!
The model plane took off from the conveyor belt.
The pilot of the ultra light thought he woulden't take off.
When they tested it the plane took off.
tom
tallyho8
Elite Member
- Joined
- Aug 1, 2004
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- 4,543
- Tractor
- Kubota L4400, Kubota ZD326
Re: Mythbusters/airplane/treadmill
The mythbusters did OK in proving the plane would take off but I like my experiment better.
http://www.tractorbynet.com/forums/...ke-off-76.html?highlight=conveyor#post1102128
The mythbusters did OK in proving the plane would take off but I like my experiment better.
http://www.tractorbynet.com/forums/...ke-off-76.html?highlight=conveyor#post1102128
RonMar
Elite Member
Re: Mythbusters/airplane/treadmill
They did an excellent job of explaining why the conveyor or treadmill didn't impede the aircraft's takeoff by using the model car. Jamie summarized it perfectly, the aircraft engine dosn't power the wheels.
I was very surprised that their pilot didn't think it would work. The only difference in his takeoff was that his wheel RPM on the moving belt was twice what it normally was... The airplane dosn't care what the ground is doing, it is only interested in airspeed over the wings.
This messes up pilots every now and then who aren't used to flying in the wind, or don't have their head in the game. While flying downwind in the traffic patern close to the ground, they get the impression of flying very fast(their airspeed + the wind speed) past the trees/terrain. Faster than they are used to when flying this pattern in a no-wind situation. An inexperienced pilot, or one who is not very well trained will follow his instincts and perception of traveling too fast and slow down to what seems a more normal pattern speed. This happens usually about the time they have to start their crosswind turn toward the runway to land. In slowing down, they bring the airspeed close to the stall speed and the added loading of the turn causes the aircraft to stall or perhaps even spin. Not having much altitude to recover and being completely surprised by the event, they usually crash. An experienced or well trained pilot will know to disregard the trees blurring by below the aircraft and fly the appropriate indicated airspeed.
tommu56 said:
They did an excellent job of explaining why the conveyor or treadmill didn't impede the aircraft's takeoff by using the model car. Jamie summarized it perfectly, the aircraft engine dosn't power the wheels.
I was very surprised that their pilot didn't think it would work. The only difference in his takeoff was that his wheel RPM on the moving belt was twice what it normally was... The airplane dosn't care what the ground is doing, it is only interested in airspeed over the wings.
This messes up pilots every now and then who aren't used to flying in the wind, or don't have their head in the game. While flying downwind in the traffic patern close to the ground, they get the impression of flying very fast(their airspeed + the wind speed) past the trees/terrain. Faster than they are used to when flying this pattern in a no-wind situation. An inexperienced pilot, or one who is not very well trained will follow his instincts and perception of traveling too fast and slow down to what seems a more normal pattern speed. This happens usually about the time they have to start their crosswind turn toward the runway to land. In slowing down, they bring the airspeed close to the stall speed and the added loading of the turn causes the aircraft to stall or perhaps even spin. Not having much altitude to recover and being completely surprised by the event, they usually crash. An experienced or well trained pilot will know to disregard the trees blurring by below the aircraft and fly the appropriate indicated airspeed.
MrJimi
Elite Member, Rest in Peace
Re: Mythbusters/airplane/treadmill
I missed this but where did the airspeed/airflow come from? did they have a fan or something?
Thanks
I missed this but where did the airspeed/airflow come from? did they have a fan or something?
Thanks
scesnick
Veteran Member
Re: Mythbusters/airplane/treadmill
The only reson BOTH planes took off from the conveyor belt was because they both simply overcame the speed of the tarp, moved forward and began getting wind under the wings producing lift.
I thought the myth was if the plane could take off while PRECISELY matching the conveyor speed. Any knuckle head could have told you that if the plane goes faster than the conveyor and gets air under its wings, it is going to fly.
So, why did the Myth Busters take the time to find the take off speed if they were not going to match the planes takeoff speed with the conveyor? Wasn't the whole to get the plane to sit still and the conveyor moving at the takeoff speed?
The only reson BOTH planes took off from the conveyor belt was because they both simply overcame the speed of the tarp, moved forward and began getting wind under the wings producing lift.
I thought the myth was if the plane could take off while PRECISELY matching the conveyor speed. Any knuckle head could have told you that if the plane goes faster than the conveyor and gets air under its wings, it is going to fly.
So, why did the Myth Busters take the time to find the take off speed if they were not going to match the planes takeoff speed with the conveyor? Wasn't the whole to get the plane to sit still and the conveyor moving at the takeoff speed?
RayH
Banned
Re: Mythbusters/airplane/treadmill
They did match tak off speed, but it really doesnt matter. The whole "conveyor" question is a red herring. It doesnt matter what speed the conveyor is going. It could be going three times the planes speed beckwards, it could be going mach 7 beckwards or the speed of light, it doesnt matter because the conveyor speed has absolutely nothing what so ever to do with whether or not the plane takes off. The only thing that allows or doesnt allow the plane to take off is airspeed and that is a product of the prop pulling the plane forward in relation to the air, not in relation to the ground or the conveyor.
They did match tak off speed, but it really doesnt matter. The whole "conveyor" question is a red herring. It doesnt matter what speed the conveyor is going. It could be going three times the planes speed beckwards, it could be going mach 7 beckwards or the speed of light, it doesnt matter because the conveyor speed has absolutely nothing what so ever to do with whether or not the plane takes off. The only thing that allows or doesnt allow the plane to take off is airspeed and that is a product of the prop pulling the plane forward in relation to the air, not in relation to the ground or the conveyor.
scesnick
Veteran Member
Re: Mythbusters/airplane/treadmill
Ray,
I understand totally what you are saying now. The only thing that the conveyor speed does is spin the wheels on the airplane faster, the plane is still going to move forward no matter what since it is driven by the prop.
So, if the take off speed is say 100 mph and the conveyor is going say 50 MPH. the wheels on the airplane are going to be turning at a rate of 150 MPH but the plane is only going 100 mph at the time of lift off.
BUT, if somehow the plane was driven by the wheels, then the senerio would be totally different. If the takeoff speed was matched by the conveyor, then the plane would just be sitting still ( with the wheels spinning) but no air would be going under the wings to acheive flight because the only thing moving on the plane IS the wheels.
Ray,
I understand totally what you are saying now. The only thing that the conveyor speed does is spin the wheels on the airplane faster, the plane is still going to move forward no matter what since it is driven by the prop.
So, if the take off speed is say 100 mph and the conveyor is going say 50 MPH. the wheels on the airplane are going to be turning at a rate of 150 MPH but the plane is only going 100 mph at the time of lift off.
BUT, if somehow the plane was driven by the wheels, then the senerio would be totally different. If the takeoff speed was matched by the conveyor, then the plane would just be sitting still ( with the wheels spinning) but no air would be going under the wings to acheive flight because the only thing moving on the plane IS the wheels.
Re: Mythbusters/airplane/treadmill
As stated, I watched Kansas State put the kabosh to previously unbeaten Kansas last night and have not gone back to watch the episode. That will be a project for THIS evening. I had no doubt that the plane would take off though. So.. did anyone go resurrect the old thread yet? lmao Surely there must be a thousand or more "I told you so's" in order...
As stated, I watched Kansas State put the kabosh to previously unbeaten Kansas last night and have not gone back to watch the episode. That will be a project for THIS evening. I had no doubt that the plane would take off though. So.. did anyone go resurrect the old thread yet? lmao Surely there must be a thousand or more "I told you so's" in order...
