Mythbusters....

wsuffa

wsuffa

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Bill S.
So Mythbusters aired an episode last night compiling and recalling their top "transportation" myths that they evaluated. And one of the top 10?




(wait for it)...





(wait for it)...





(wait for it)...


Plane on a treadmill.

They specifically mentioned how tall the stack of internet posts was from folks arguing about the question (pretty tall) and that it persists to this day.

Y'all are infamous....
 
What exactly is the 'plane on a treadmill' concept ?
 
ScottM said:
That a plane cannot take off from a treadmill while following the magenta line of death unless the pilots shouts ATITAPA!
Click to expand...

Ah, I guess it would work if they just leaned forward !
 
I was pretty embarrassed for pilots everywhere, when the "pilot" they hired said a plane COULD NOT take off from a treadmill "because there would be no speed"....

I hope he was just confused at the question....
 
wsuffa said:
So Mythbusters aired an episode last night compiling and recalling their top "transportation" myths
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I was expecting a "new" episode - I hate "compilation" episodes. May as well have just repeated the episodes.
 
But will the shrimp take off?


As we see it does not and that should settle this for once and for all. A shrimpy airplane cannot take off from a treadmill. The Mythbusters proved nothing as they used a conveyor belt and not a treadmill. I think that was even a Kenyan conveyor belt and is thus ineligible to hold office, at least according to Mythbuster pro-tempore Oily Taintz.
 
ScottM said:
Does anyone know if a sport pilot can take off from a treadmill or do you need a type rating for that?
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It's different surface so it's a different rating: Aircraft, Single Engine, Treadmill (ASET). :rofl:

John
 
Has everyone forgotten the need for a flight plan?
 
ajstoner21 said:
I was pretty embarrassed for pilots everywhere, when the "pilot" they hired said a plane COULD NOT take off from a treadmill "because there would be no speed"....

I hope he was just confused at the question....
Click to expand...


You too huh?

I could see where the plane might not make it to lift off speed (due to the rolling resistance of the wheels) but to think it would just "sit there like a brick" :mad2:
 
I used to think Mythbusters were cool....then I saw a Reliant Robin made into a space shuttle and changed my loyalties and I have POA to thank for this!
 
Fearless Tower said:
I used to think Mythbusters were cool....then I saw a Reliant Robin made into a space shuttle and changed my loyalties and I have POA to thank for this!
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Have these other guys made a cement truck dissappear like on Mythbusters?
 
Palmpilot said:
I couldn't find a thread on PoA, but here's one on the Red Board:

http://forums.aopa.org/showthread.php?t=17633
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You have to wonder if anyone from the FAA reads this stuff and if they contemplate emergency revocations for being too stupid to fly.

<named deleted to protect the guilty> said:
CRJ-900 First Officer
CFI/CFII/AGI/IGI, CL-65
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And yet he couldn't comprehend numerous clear explanations of how aircraft are propelled by exerting force on the air, not land. Woooaaaah.
 
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Skylane81E said:
You too huh?

I could see where the plane might not make it to lift off speed (due to the rolling resistance of the wheels) but to think it would just "sit there like a brick" :mad2:
Click to expand...

I've heard that the rolling resistance of an airplane is pretty much independent of speed. One person can overcome the rolling resitance of light airplanes to push them into their parking spots, and I doubt that one person could hold a plane back when takeoff thrust was applied, so it looks to me like rolling resistance is not going to be enough to do the job.
 
ScottM said:
Does anyone know if a sport pilot can take off from a treadmill or do you need a type rating for that?
Click to expand...

ajstoner21 said:
I was pretty embarrassed for pilots everywhere, when the "pilot" they hired said a plane COULD NOT take off from a treadmill "because there would be no speed"....

I hope he was just confused at the question....
Click to expand...

Yeah. Note that he was an ultralight (not even Sport) pilot. I ain't laying claim to him.
 
Palmpilot said:
I couldn't find a thread on PoA,
Click to expand...

Yeah. It's never been discussed here.

This may be the first thread submitted by some wisenheimer kid who was trolling:

http://www.pilotsofamerica.com/forum/showthread.php?t=4801&highlight=treadmill

But then....

http://www.pilotsofamerica.com/forum/showthread.php?t=19076&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=17907&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=18374&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=18167&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=5566&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=16319&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=13707&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=11239&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=12618&highlight=treadmill

903.jpg
 
Palmpilot said:
I've heard that the rolling resistance of an airplane is pretty much independent of speed. One person can overcome the rolling resitance of light airplanes to push them into their parking spots, and I doubt that one person could hold a plane back when takeoff thrust was applied, so it looks to me like rolling resistance is not going to be enough to do the job.
Click to expand...

I agree, it's just the ONLY thing that the plane has to overcome vs a regular T/O run. ie wheel drag @ 45kts < @ 90kts.

Or to look at it another way can you take off with a tailwind that matches your liftoff speed? And to make it easier in this experiment you are already matching the wind speed;)
 
Mike,

The phraseology of the "problem" in that cartoon is interesting. It references the speed of the wheels and not the speed of the plane. The plane must be stationary for the conveyor belt speed to match the speed of the wheels. In reality, I doubt that that would be possible to achieve and test.

Theoretically though, the conveyor would need to accelerate very quickly, to a very high speed, in order to create enough friction to hold the plane stationary, then the bearings would overheat, the wheels would lock up, and the plane would quickly accelerate from 0 to (oh, say) 500 knots...

...backwards.

It'd be fun to watch though.

Well, except that, again, if the conveyor was perfectly synchronized with the wheels, then it would come to a screeching halt as soon as the wheels locked up so the plane would still never move (assuming the speed sensor was on the wheel that locks up first otherwise we're back to a quick acceleration to 500 knots in reverse).
 
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I noticed that too Tim. Yeah if the belt could manage to ALWAYS match the speed of the wheels then yes the plane would remain set in place as there is a point where the drag of the wheels will match the thrust of the engine, but how the hell could you ever do that?
 
mikea said:
Yeah. It's never been discussed here.

This may be the first thread submitted by some wisenheimer kid who was trolling:

http://www.pilotsofamerica.com/forum/showthread.php?t=4801&highlight=treadmill

But then....

http://www.pilotsofamerica.com/forum/showthread.php?t=19076&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=17907&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=18374&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=18167&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=5566&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=16319&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=13707&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=11239&highlight=treadmill

http://www.pilotsofamerica.com/forum/showthread.php?t=12618&highlight=treadmill
Click to expand...

I see my problem...I only searched for "treadmill" in the title, not in the text, and I didn't try searching on the word "conveyor."
 
timwinters said:
Mike,

The phraseology of the "problem" in that cartoon is interesting. It references the speed of the wheels and not the speed of the plane. The plane must be stationary for the conveyor belt speed to match the speed of the wheels. In reality, I doubt that that would be possible to achieve and test.
Click to expand...

Skylane81E said:
I noticed that too Tim. Yeah if the belt could manage to ALWAYS match the speed of the wheels then yes the plane would remain set in place as there is a point where the drag of the wheels will match the thrust of the engine, but how the hell could you ever do that?
Click to expand...

Yeah. Not again. One of the things leading to the long discussions is the ones where the problem is stated wrong. It was intended that the conveyor match the forward speed of the plane, not the wheels.

Could we please, please, please, please, please not rehash all of that again?
 
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mikea said:
Searching for "conveyor" finds a few more (some may be dupes with those above):

http://www.pilotsofamerica.com/forum/showthread.php?t=19076&highlight=conveyor

http://www.pilotsofamerica.com/forum/showthread.php?t=5566&highlight=conveyor
http://www.pilotsofamerica.com/forum/showthread.php?t=18374&highlight=conveyor
http://www.pilotsofamerica.com/forum/showthread.php?t=18167&highlight=conveyor

and sorta

http://www.pilotsofamerica.com/forum/showthread.php?t=4813&highlight=conveyor
Click to expand...

Adam and Jaime held up a stack of papers about 3 inches tall which was a printout of the internet arguments & discussions of plane-on-a-treadmill. They also noted that there are some heathe.... er.... unbelievers that still insist on arguing the point.
 
I just watched the episode and the 'Mythbusters' didn't conduct the experiment according to the myth that's being discussed here. They simply simulated a tail wind. If the plane is moving forward through the air (in the episode it was) then of course it'll will take off when it reaches Vr. The wheels mean nothing.

If the conveyor is moving in the OPPOSITE direction of the plane at the exact speed of the plane then the plane will never see any forward ground speed or airspeed other than what the prop generates - and the headwind. The prop alone isn't going to generate enough wind (volume or velocity) for the wings to see Vr airspeed therefore forward motion will be required.

Myth confirmed.
 
MadseasoN said:
I just watched the episode and the 'Mythbusters' didn't conduct the experiment according to the myth that's being discussed here. They simply simulated a tail wind. If the plane is moving forward through the air (in the episode it was) then of course it'll will take off when it reaches Vr. The wheels mean nothing.

If the conveyor is moving in the OPPOSITE direction of the plane at the exact speed of the plane then the plane will never see any forward ground speed or airspeed other than what the prop generates - and the headwind. The prop alone isn't going to generate enough wind (volume or velocity) for the wings to see Vr airspeed therefore forward motion will be required.

Myth confirmed.
Click to expand...

I thought trolling was prohibited.
 
MadseasoN said:
I just watched the episode and the 'Mythbusters' didn't conduct the experiment according to the myth that's being discussed here. They simply simulated a tail wind. If the plane is moving forward through the air (in the episode it was) then of course it'll will take off when it reaches Vr. The wheels mean nothing.

If the conveyor is moving in the OPPOSITE direction of the plane at the exact speed of the plane then the plane will never see any forward ground speed or airspeed other than what the prop generates - and the headwind. The prop alone isn't going to generate enough wind (volume or velocity) for the wings to see Vr airspeed therefore forward motion will be required.

Myth confirmed.
Click to expand...

Really? :mad2::mad2::mad2::mad2::mad2:

Tell me, when you line up on the runway centerline, and apply full throttle - why does your airplane move?
 
TMetzinger said:
Tell me, when you line up on the runway centerline, and apply full throttle - why does your airplane move?
Click to expand...

It's PFM.

The whole thing is PFM, with absolutely wonderful results (i.e., flight for those that don't know), but its just PFM.

:)
 
MadseasoN said:
I just watched the episode and the 'Mythbusters' didn't conduct the experiment according to the myth that's being discussed here. They simply simulated a tail wind. If the plane is moving forward through the air (in the episode it was) then of course it'll will take off when it reaches Vr. The wheels mean nothing.

If the conveyor is moving in the OPPOSITE direction of the plane at the exact speed of the plane then the plane will never see any forward ground speed or airspeed other than what the prop generates - and the headwind. The prop alone isn't going to generate enough wind (volume or velocity) for the wings to see Vr airspeed therefore forward motion will be required.

Myth confirmed.
Click to expand...

Please tell us all that you're not serious. :dunno:
 
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