Mythbusters/will it fly?

[USMARINE1108]

So who else is pissed?

oh well, we all know it'll fly anyway!

[Waver]

so it didnt fly....I thought it would be like the verticle take off jet, the harrier

[07ROUSHSTG3]

they didnt do it! what a bust.

[USMARINE1108]

so it didnt fly....I thought it would be like the verticle take off jet, the harrier

No, they showed previews for it, it was all over the Mythbusters website and they just didn't air the segment. Total bait-n-switch like the "who's Cartman's father" south park episode about 10 years ago. The Mythbusters are turds.

[PonyKiller87]

So do you think they made the promo crap for it and then realized that

1. building a conveyor belt that big is way out of thier budget / league
2. its hard to find someone with a plane there willing to play with.
- If they really did it to the letter of the myth... conveyor continues to spin faster as the wheels speed up, the conveyor would be going infinitaly fast and it or the planes wheel bearings would fry out by the time the plane took off.


Oh yeah, I'm on the side that says yes it will take off. otherwise known as the correct side.

[Waver]

So do you think they made the promo crap for it and then realized that

1. building a conveyor belt that big is way out of thier budget / league
2. its hard to find someone with a plane there willing to play with.
- If they really did it to the letter of the myth... conveyor continues to spin faster as the wheels speed up, the conveyor would be going infinitaly fast and it or the planes wheel bearings would fry out by the time the plane took off.


Oh yeah, I'm on the side that says yes it will take off. otherwise known as the correct side.

well they could of used a smaller jet/plane

[juicedimpss]

Oh yeah, I'm on the side that says yes it will take off. otherwise known as the correct side.

:thumbsup

[USMARINE1108]

Apparently they already filmed it. They used a 1/4mile belt and an ultralight. I'll see if I can dig up a link someplace.

[BAD LS1]

This test is WAYYYY cooler!

http://www.youtube.com/watch?v=eTQh7D-nDNM

[ThatWhiteCivic]

That was pretty cool ^^^^

[BadAzzGTA89]

They could have used paper airplanes:goof
But no really why not go to a boneyard and get a single person plane for the test??

[0TransAm0]

why not use a remote controle airplane a frigin tredmill... either way i was pissed they didn't do it...

[lilws6]

glad i missed it cuz my mom just told me about it and said they didm't do the test as well now i'm pissed also lol

[badass88gt]

http://www.kottke.org/07/12/internet-pissed-at-mythbusters-for-not-showing-airplane-on-a-treadmill

It'll be on January 30th.

[USMARINE1108]

why not use a remote controle airplane a frigin tredmill... either way i was pissed they didn't do it...

Look in my first thread on the last page, there's a link to a youtube video of someone doing that.

[USMARINE1108]

^
crap, that thread is gone, isn't it.

I can't get to youtube at work to get you a link, but if you just google "airplane treadmill video" it should come up.

[Cryptic]

bump... I believe they are doing this right now...

Discovery Channel 8pm today

[Cryptic]

they did it with a model plane and a treadmill... the plane did not fly.

[Cryptic]

ok wait.. they are still doing a FULL SCALE experiment.

[pickardracing]

I want to bork Kari. Bad.

[GTSLOW]

This test is WAYYYY cooler!

http://www.youtube.com/watch?v=eTQh7D-nDNM

I can't believe that bus got airborne!! :wooo

[lasttimearound]

i want to bork kari too

[pickardracing]

i want to bork kari too

Sloppy seconds for you.

[lasttimearound]

ill take it

[pickardracing]

lol




.

[Prince Valiant]

To be honest...I don't even know anymore what they are trying to test...I've heard this explained to me various ways, and each would give a different result imo.

[pickardracing]

It Takes Off

[lasttimearound]

so it flew..

[lasttimearound]

**damn you! beating me to everything

[Cryptic]

it flew... seemed retarded to me. Its air speed over the wings, not speed over ground

[pickardracing]

**damn you! beating me to everything

http://www.greatmodernpictures.com/nmato8lg.jpg

[Prince Valiant]

That's the thing:

1. If it's just held in one place and a conveyor belt runs under it w/o the plane moving...it won't fly.

2. If it's using it's own power ON the conveyor belt, it'll eventually overcome the rolling resistance/inertia and propel itself to speeds enough so it'll get lift, and fly.

Seems to me is that the only thing this problem was really about is that people are often times incapable of communicating to 100% of the people 100% of the time. I'd read one explanation and say "true", and another and also say "true" given how it was spelled out...

...but it was clear that each were saying vastly different things.


You know what Mythbuster I'D love to see? One where they recreate all the lame truck commercials like stopping airplanes, dropping huge weights, ridiculous start stop test.

[juicedimpss]

hmmm
who is it that said it wouldnt fly........

[Cryptic]

Chris... Looks like they already have a Tundra for the test.

[MoCkiN U]

It didnt sit still like you would visualize on a conveyor and take off. Thats the myth. It actually just over powered the jerry rigged conveyor wanna be. The plane traveled like 30 ft down this rig they made and took off.

I wanted to see it sit still like the small scale test and try to take off. The celebrated on the show like they did something but the made a ultralite take off from a carpet. That happens everyday seems like.

[Reverend Cooper]

wont ever fly try again. gravity+no lift=fail

[pickardracing]

Jesus Christ...

[badass88gt]

Dammit, I missed it????


I forgot all about it. SO the thing flew? Sweet.

[Reverend Cooper]

test is falible

[CannotPost]

I want to bork Kari. Bad.

I Second the motion!

[Mr Twigbert]

It didnt sit still like you would visualize on a conveyor and take off. Thats the myth. It actually just over powered the jerry rigged conveyor wanna be. The plane traveled like 30 ft down this rig they made and took off.

I wanted to see it sit still like the small scale test and try to take off. The celebrated on the show like they did something but the made a ultralite take off from a carpet. That happens everyday seems like.

I agree.. This is how I see it..

Mythbusters said 100 times that if the treadmill is running at the SAME EXACT SPEED as the plane would it take off?

The problem with this is they ran the plane up to MAX power and it over came the speed of the treadmill..

If the plane only needs, say, 4,000 RPMS to meet the 25 MPH of speed and the plane sits still it won't take off.. BUT, Mythbusters ran the plane up to MAX RPM and the plane over came the speed of the conveyor belt and began to travel faster than the 25 MPH..

What a complete bust..

[6forwardgears]

I agree.. This is how I see it..

Mythbusters said 100 times that if the treadmill is running at the SAME EXACT SPEED as the plane would it take off?

The problem with this is they ran the plane up to MAX power and it over came the speed of the treadmill..

If the plane only needs, say, 4,000 RPMS to meet the 25 MPH of speed and the plane sits still it won't take off.. BUT, Mythbusters ran the plane up to MAX RPM and the plane over came the speed of the conveyor belt and began to travel faster than the 25 MPH..

What a complete bust..

How is it a complete bust?

Nobody on this planet honestly thinks a plane at a stand still will take off. The entire point of the argument when you strip it down to its core is "Can a treadmill hold a plane stationary?" And the answer is, no it can't.

[juicedimpss]

didnt the original question state something about the treadmill moving "as fast as the WHEELS on the plane"??

[madmike]

I want to join the mile high club with Kari!!!!

[Mr Twigbert]

How is it a complete bust?

Nobody on this planet honestly thinks a plane at a stand still will take off. The entire point of the argument when you strip it down to its core is "Can a treadmill hold a plane stationary?" And the answer is, no it can't.

I think your wrong.. I think LOTS of people think if the plane has its engine running it will magically make the plane fly..

On a side note.. I drove past the maro today that you have in your avatar.. Its in the falls.. I looked over and was like WTF!

[BAD LS1]

On a side note.. I drove past the maro today that you have in your avatar.. Its in the falls.. I looked over and was like WTF!

This beauty? hahahahah i work at the end of lilly road and couldnt resist stopping and shooting pcs of it in all of its suspension articulation glory.

http://i264.photobucket.com/albums/ii173/LS1builder/IMG_0224.jpg


http://i264.photobucket.com/albums/ii173/LS1builder/IMG_0226.jpg

[USMARINE1108]

It blows my mind how some people still don't get it. It doesn't matter how fast the treadmill is going. http://www.youtube.com/watch?v=-EopVDgSPAk

[Prince Valiant]

The only thing the plane has to overcome on a treadmill is rolling ressistance. It's significant at first but as soon as the wheels move, it's fairly light.

[Reverend Cooper]

didnt the original question state something about the treadmill moving "as fast as the WHEELS on the plane"??

EXACTLY!!!!!!!! the treadmill matches the planes wheel speed and the plane can not fly. if you take a treadmill and put it at ten mph then start the plane moving and it has the capability of over ten mph say 20 mph yes it will fly, it is the same a a stationary tarmac and the plane going ten mph. sooo if the treadmill matches the planes speed it cant fly

[USMARINE1108]

EXACTLY!!!!!!!! the treadmill matches the planes wheel speed and the plane can not fly. if you take a treadmill and put it at ten mph then start the plane moving and it has the capability of over ten mph say 20 mph yes it will fly, it is the same a a stationary tarmac and the plane going ten mph. sooo if the treadmill matches the planes speed it cant fly

Your logic is full of fail.

[Prince Valiant]

Mike and ron are absolutely correct too...THATS THE WHOLE THING!

people have been TRYING to talk about the same thing, but haven't.

IF the treadmill IS moving in the opposite direction of the wheels at the same speed, THE PLANE WON'T TAKE OFF!!! Net speed = 0= no fly

But, in the real world, this won't/really CAN'T happen. So the plane fly's.

[pickardracing]

Just stop. Seriously.

[6forwardgears]

Just stop. Seriously.

NEVAR!!!!111one


Mike and ron are absolutely correct too...THATS THE WHOLE THING!

people have been TRYING to talk about the same thing, but haven't.

IF the treadmill IS moving in the opposite direction of the wheels at the same speed, THE PLANE WON'T TAKE OFF!!! Net speed = 0= no fly

But, in the real world, this won't/really CAN'T happen. So the plane fly's.

If it can't happen in the real world... what point are you trying to make? The normal laws of physics apply to the real world.

[Prince Valiant]

If it can't happen in the real world... what point are you trying to make? Duh...could it be a riddle?

It ask the listener to think about the question asked...not neccessarily the "real world" Since when do question only deal 100% exclusively with reality?

Ron and Mike are absolutely correct. As they possit, it can't happen. You won't hear that and keep bullheadedly refusing to accept the question at face value.

Face it, as asked, the question was probably made up by someone who just gets a kick out of retards arguing on the internet.

[Mr Twigbert]

It blows my mind how some people still don't get it. It doesn't matter how fast the treadmill is going. http://www.youtube.com/watch?v=-EopVDgSPAk

I want to disagree but really can't after watching that video..

[Moparjim]

Blows my mind as well. The thing flys. End of discussion. The plane is driven by THRUST from the prop or the jet turbine acting on the AIR, not the wheels on conveyor. Doesn't matter **** what the conveyor does, the wheels just freewheel. All of you people are hung up thinking of it like a CAR not like a plane. THRUST moves the plane forward, creating lift, plane flys.

[6forwardgears]

Blows my mind as well. The thing flys. End of discussion. The plane is driven by THRUST from the prop or the jet turbine acting on the AIR, not the wheels on conveyor. Doesn't matter **** what the conveyor does, the wheels just freewheel. All of you people are hung up thinking of it like a CAR not like a plane. THRUST moves the plane forward, creating lift, plane flys.

Actually I think most people understand that the airplane is not powered through the wheels.

The problem comes in where people have the misconception that a treadmill can hold a plane stationary. So many people hear the phrase "if a plane's speed is matched by a treadmill moving in the opposite direction", and they immediately assume that "matching speed" means that the plane won't move. Then, to them it becomes a discussion of "well if the plane isn't moving, of course it won't take off."

The whole argument can be settled simply by saying, the conveyor belt cannot hold the plane still no matter what. You could have the conveyor belt shoot into full speed at 400mph and the plain would still take off just fine.

(I'm not arguing with your post obviously, just trying to explain why I think there is such a debate about this)

[badass88gt]

It flew. End of story. What more is there to debate? How long will it fly for? How high will it go? Seriously....

[USMARINE1108]

Just stop. Seriously.

You don't have to read the thread. :thumbsup




The whole argument can be settled simply by saying, the conveyor belt cannot hold the plane still no matter what.


Truth. People get stuck on the plane standing in one spot (belt matches the speed of the wheels) but in reality it will accelerate.

[Prince Valiant]

Truth. People get stuck on the plane standing in one spot (belt matches the speed of the wheels) but in reality it will accelerate.You are correct. In reality, it'll accelerate and fly.

But, that's not what the question ask (as ron posit it). That's what you refuse to accept.

It's a trick question imo.

[USMARINE1108]

You are correct. In reality, it'll accelerate and fly.

But, that's not what the question ask (as ron posit it). That's what you refuse to accept.

It's a trick question imo.


The way I asked the question in August was that the conveyer matches the speed of the wheels. This does not mean the airplane will not fly. In fact, it has absolutely nothing to do with the airplane flying. It means that the wheels will be spinning 2x the speed of the aircraft.

[6forwardgears]

You are correct. In reality, it'll accelerate and fly.

But, that's not what the question ask (as ron posit it). That's what you refuse to accept.

It's a trick question imo.

You're right, it is a trick question, designed to trick people who don't have a good understanding of the physics involved. But no matter how the question is worded (short of "Will a plane at rest take off?") the answer is always "yes, it will take off". You can say 8 million different wordings of the treadmill matching the plane's speed, or moving in the opposite direction of the plane equal to its forward speed, or whatever, the outcome is always exactly the same!!!

[05caddyext]

You could have the conveyor belt shoot into full speed at 400mph and the plain would still take off just fine.



I have to disagree with that one.

[6forwardgears]

I have to disagree with that one.

Explain why?

Other than the fact that tires and wheel bearings would fail. Assuming that you had some special ones that could handle 600+mph... why would the plane not take off?

[Knyghtmare]

The plane was still moving forward as the "conveyor" was going in the oposite direction. Which was probably mostly because of the weight of the plane on a burlap sack being pulled out from underneath it, the plane appeared to have traction regardless of what was under it. In my opinion thats a non accurate test... If the "conveyor" was truley matching the speed of the plane's take off speed(and the weight of a plane on lightweight burlap wasnt a factor), instead of just a constant speed, then the plane would have stayed in place moving along the "conveyor" as it was pulled beneath it until the plane would have gained lift and the wheels left the berlap rug it was on. Since a plane obtains lift from air moving around the wings, it wouldnt have been able to gain lift had the "conveyor" been matching the planes speed as it sped up. Havent any of you guys walked backwards on the moving walkways at O'Hare? Instead (again if the weight of the plane still creating traction wasnt a factor) the plane compensated for the constant loswer speed of the "conveyor" and was moving faster and still moved forward to gain enough speed and lift under the wings to take off.

I understand that the idea of the test was to just get the "conveyor" moving at whatever the normal take off speed of the plane was, but I think it would have been more interesting if Jamie would have kept accelerating the "conveyor" along with the plane to match the planes speed the entire time.

[UnderPSI]

I can't belive this is still an issue:durr

The wheels could be going 1,000miles an hour backwards on a treadmill and the plane would still take off pulling its self throught the stationary air. The plane doesn't drive forward with its wheels to take off, the propeller pulls it.

[6forwardgears]

The plane was still moving forward as the "conveyor" was going in the oposite direction. Which was probably mostly because of the weight of the plane on a burlap sack being pulled out from underneath it, the plane appeared to have traction regardless of what was under it. In my opinion thats a non accurate test... If the "conveyor" was truley matching the speed of the plane's take off speed(and the weight of a plane on lightweight burlap wasnt a factor), instead of just a constant speed, then the plane would have stayed in place moving along the "conveyor" as it was pulled beneath it until the plane would have gained lift and the wheels left the berlap rug it was on. Since a plane obtains lift from air moving around the wings, it wouldnt have been able to gain lift had the "conveyor" been matching the planes speed as it sped up. Havent any of you guys walked backwards on the moving walkways at O'Hare? Instead (again if the weight of the plane still creating traction wasnt a factor) the plane compensated for the constant loswer speed of the "conveyor" and was moving faster and still moved forward to gain enough speed and lift under the wings to take off.

I understand that the idea of the test was to just get the "conveyor" moving at whatever the normal take off speed of the plane was, but I think it would have been more interesting if Jamie would have kept accelerating the "conveyor" along with the plane to match the planes speed the entire time.

This post pretty much exemplifies the misconceptions I identified in my previous posts.

Take your example of walking along the walkways at O'Hare. Your feet provide your forward motion, that's why you don't go anywhere if you walk against the walkway at the same speed the conveyor. A plane, however, relies on AIR to move itself a long. Therefore, the only thing that happens when the conveyor is moving underneath the airplane is that the wheels spin a little faster.

Did you watch the part of the episode (before they did the Ultralight experiment) where they explained everything with some basic diagrams?

It doesn't matter how fast Jamie accelerated when the experiment started. He could have had the tarp attached to a Formula 1 car and the end result would have been exactly the same.

[Knyghtmare]

I can't belive this is still an issue:durr

The wheels could be going 1,000miles an hour backwards on a treadmill and the plane would still take off pulling its self throught the stationary air. The plane doesn't drive forward with its wheels to take off, the propeller pulls it.

True. The propeller pulls it, but the propeller doesnt get the air moving around the wings to get the lift... the propeller pulls the plane through the air up to speed to get the air around the plane to lift under the wings to get it to take off. A plane has to have forward motion to gain lift.

Think of it this way. Your driving your car on the road and you stick your hand out your open window and you can simulate the way a wing creates lift, we have all done it Im sure. Now think of doing the same thing while your car is on the Dyno... Your wheels are moving, but there is no motion through the air, the air isnt passing by the car at the speed your wheels are turning and so there is no air motion to create that lift on your hand.

[UnderPSI]

The propeller spinning provides the forward motion the wheels can free spin backwards as much as they want.

You could put a wheel barrow on a treadmill and spin it up as fast as you can get it to go and you would still be able, using your arms to provide the motion, to push it forward and back ward.

If the wheels of the plane are spinning backward it isn't like putting the brakes on. The propeller will still pull it forward. There isn't much resistance in a free-spinning wheel.

[UnderPSI]

Your wheels are moving, but there is no motion through the air, the air isnt passing by the car at the speed your wheels are turning and so there is no air motion to create that lift on your hand.


If the car wasn't strapped down and there was a propeller on it, it would get pulled of the dyno. It doesn't matter if there are wheels spinning backwards, or staionary or if the plane has pontoons on it the propeller will pull it forward and the planes wings will create lift

[Knyghtmare]

Hmmm, I see what your sayin... lemme check it out on You Tube again...

[UnderPSI]

All the planes wheels are doing is holding the plane off the ground. It doesn't matter what else they do, it is just a free spinning wheel. It just provides support. Thrust is what makes it go forward.

[Knyghtmare]

Alright, im seeing it from your prospective. I was looking at it a totally different way from contact with the ground and weight with the ground. I dont see how a stationary plane, no matter how fast the propeller is turning, as long as the plane isnt moving in a forward direction, can create the lift under the wings to get it off the ground... I guess I was thinking if a plane has its propeller going at max rpm and was strapped down and the plane wasnt moving forward and making air move over the wings it wouldnt get off the ground... but then again its the same way a plane takes off from an Aircraft carrier thats moving, its still going to take off. Its getting pulled through the air, not getting pushed by contact on the ground.

[Prince Valiant]

The way I asked the question in August was that the conveyer matches the speed of the wheels. This does not mean the airplane will not fly. In fact, it has absolutely nothing to do with the airplane flying. It means that the wheels will be spinning 2x the speed of the aircraft.BZZZZT! WRONG!

If the converyor and wheels are actually moving the same speed, there is NO net motion. Think about it.

In reality this wouldn't happen....we know this.

But in order for the motion to occur, the wheels HAS to turn faster than the conveyor belt...IE, in order for the plane to go 10 mph on a conveyor belt traveling the opposite direction at 10mph, the wheels has to be turning at a speed of 20mph.

That's not the same speed...the conveyor belt isn't MATCHING the speed of the wheels...it's going slower by 10mph.

You are correct...it IS twice the speed of the airplane...but also twice the speed of the conveyor belt too. Okay, so speed the conveyor belt up to 20mph...now the wheels are going 30mph for the plane to continue at 10mph. THE ONLY WAY THAT THE "the conveyer matches the speed of the wheels" IS WITH NO NET MOTION!!!

That's the ONLY way it can happen.

So, in reality, as long as the plane is moving, it CAN'T match the speed of the airplanes wheels...BUT at it's face value, the question is worded so that the plane is in fact, not moving....

It's STILL a trick question with no basis in reality. That's where everyone gets tripped up.

[USMARINE1108]

in order for the plane to go 10 mph on a conveyor belt traveling the opposite direction at 10mph, the wheels has to be turning at a speed of 20mph.

That's not the same speed...the conveyor belt isn't MATCHING the speed of the wheels...it's going slower by 10mph.



Um, thanks for proving my point? What you just described is if the conveyor belt matched the speed of the aircraft. That's not the case. If the aircraft is moving 10kts and the conveyor matches the speed of the wheels, the wheels and conveyor will both be at 20kts. The wheels and conveyor will always be moving at 2x the speed of the aircraft. As the aircraft accelerates, so will the wheels and conveyor.

[Prince Valiant]

Um, thanks for proving my point? What you just described is if the conveyor belt matched the speed of the aircraft. That's not the case. If the aircraft is moving 10kts and the conveyor matches the speed of the wheels, the wheels and conveyor will both be at 20kts. The wheels and conveyor will always be moving at 2x the speed of the aircraft. As the aircraft accelerates, so will the wheels and conveyor.
OMG :rolf I mean, this is comedy gold.

I mean...you are soooo beyond wrong.

Here, I'll try again, using several numbers...I picked 10mph in the last example because I figured it'd be easier to follow...little did I know :rolf

I'll try a number of scenario's:

1.Plane is traveling 25 mph. The wheel is traveling 25mph rolling in the SAME direction. Therefore the conveyor Cannot be MOVING.

2. Okay, plane is traveling 50mph. The tires are moving 100mph. Then the conveyor is moving 50 mph in the opposite direction.

3. The plane is moving 40 mph west. The conveyor is moving 80mph east. The wheels have to be turning 120mph west.

4. The plane is moving 1,204mph in the west direction. The wheel is turning 1,893 mph in the same direction. Then the conveyor HAS to be turning 689mph in the opposite direction.

5. Plane is traveling 65 mph. The wheels are traveling only 30 mph in the same direction. Therefore the conveyor must be traveling 35mph IN THE SAME DIRECTION.

6. The plane is traveling 100mph. The wheels are traveling 200mph in the opposite direction. The conveyor MUST be moving 300mph in the same direction of the plane!

7. If the plane is traveling 0mph. And the wheels are traveling 35mph west. Then the conveyor MUST be traveling 35mph east.

8. If plane is moving 43mph in the west direction, and the conveyor is moving 43 mph in the west direction, the the wheels are moving 0 mph.

It's a vector. Everything must add up (unless the tire is slipping on the conveyor).

Basically, the speed of the wheels must equal the difference of speed of plane and speed of conveyor.

What YOU describe in the quote above is a mathmatical impossibility. If plane moves X, and conveyor moves 2X in the opposite direction, then the wheels has to move 3X.

If plane moves X and wheels are moving 2X then the convyor HAS to be moving only 1X in the opposite direction.

Therefore, if the wheel is spinning 2X and the conveyor is traveling 2X in the opposite direction, then the plane is moving 0X...IE it is NOT moving AND not flying per the question asked.

Christ, even pulled out simple algebra.:goof

[USMARINE1108]

OMG :rolf I mean, this is comedy gold.

I mean...you are soooo beyond wrong.

Here, I'll try again, using several numbers...I picked 10mph in the last example because I figured it'd be easier to follow...little did I know :rolf

I'll try a number of scenario's:

1.Plane is traveling 25 mph. The wheel is traveling 25mph rolling in the SAME direction. Therefore the conveyor Cannot be MOVING.

2. Okay, plane is traveling 50mph. The tires are moving 100mph. Then the conveyor is moving 50 mph in the opposite direction.

3. The plane is moving 40 mph west. The conveyor is moving 80mph east. The wheels have to be turning 120mph west.

4. The plane is moving 1,204mph in the west direction. The wheel is turning 1,893 mph in the same direction. Then the conveyor HAS to be turning 689mph in the opposite direction.

5. Plane is traveling 65 mph. The wheels are traveling only 30 mph in the same direction. Therefore the conveyor must be traveling 35mph IN THE SAME DIRECTION.

6. The plane is traveling 100mph. The wheels are traveling 200mph in the opposite direction. The conveyor MUST be moving 300mph in the same direction of the plane!

7. If the plane is traveling 0mph. And the wheels are traveling 35mph west. Then the conveyor MUST be traveling 35mph east.

8. If plane is moving 43mph in the west direction, and the conveyor is moving 43 mph in the west direction, the the wheels are moving 0 mph.

It's a vector. Everything must add up (unless the tire is slipping on the conveyor).

Basically, the speed of the wheels must equal the difference of speed of plane and speed of conveyor.

What YOU describe in the quote above is a mathmatical impossibility. If plane moves X, and conveyor moves 2X in the opposite direction, then the wheels has to move 3X.

If plane moves X and wheels are moving 2X then the convyor HAS to be moving only 1X in the opposite direction.

Therefore, if the wheel is spinning 2X and the conveyor is traveling 2X in the opposite direction, then the plane is moving 0X...IE it is NOT moving AND not flying per the question asked.

Christ, even pulled out simple algebra.:goof

You are missing the point and failing on a scale never before seen. I see I need to go slow here. We'll start with something simple. What was the question I asked in August? I don't think you even remember what the question is.

[Prince Valiant]

The way I asked the question in August was that the conveyer matches the speed of the wheels. This does not mean the airplane will not fly. In fact, it has absolutely nothing to do with the airplane flying. It means that the wheels will be spinning 2x the speed of the aircraft.And then did you see how vector's must always equal?

If the conveyor equals 2X, and the wheels equal 2x in the opposite direction then plane speed equals 0.

Trust me. You = the fail.

BUT, since you are so up to it...take one, two....hell, all 8 of the above examples if you want and show where it's wrong.

Trust me...you can't.

[05caddyext]

You are missing the point and failing on a scale never before seen. I see I need to go slow here. We'll start with something simple. What was the question I asked in August? I don't think you even remember what the question is.

Physics Brainteaser - input from you smart people

--------------------------------------------------------------------------------

So the following question was posted on another message board I frequent, and it turned into a 66 page flame war with multiple bans and no answer.

"Imagine a plane is sitting on a massive conveyor belt, as wide and as long as a runway. The conveyer belt is designed to exactly match the speed of the wheels, moving in the opposite direction. Can the plane take off?"

[USMARINE1108]

And then did you see how vector's must always equal?

If the conveyor equals 2X, and the wheels equal 2x in the opposite direction then plane speed equals 0.

Trust me. You = the fail.

BUT, since you are so up to it...take one, two....hell, all 8 of the above examples if you want and show where it's wrong.

Trust me...you can't.


Alright princess. You are oversimplifying the problem. Your effort in trying to sound smart is valiant, however it's making you look like an idiot to anyone who knows what they're talking about (math, physics). You are using the wrong formula. At least, between your attempt of puffing out your chest and snide remarks, your 10th grade math/physics skills are what's apparent. Now, if you want to get into a pissing match on the internet, that's fine. I can play that game. However, I'm more interested in a debate between two people who want to find the correct answer to a problem. Can you calm down and act like an adult and stop being a Mr sassy pants?

Let's back up. Look at the original question. It asks if the airplane will take off, right? We can all agree the airplane will take off, can't we? I mean it's been proven many times, many different ways and on video. If you don't get that, read the original thread (but I think it may have been lost when the server crashed) or go to youtube and watch the many videos on the subject. You're trying to prove mathematicaly that the airplane won't fly because it doesn't make sence with the speed of the wheels/speed of the conveyor/speed of the aircraft, right? You are going about it incorrectly. Let me ask you this: In the videos you can see of the problem, how are the wheels of the airplane keeping up with the aircraft if your theory is correct? You are not accounting for thrust. You're leaving a vector out, which just happens to be the most important one in the question. Yes, your MATH works out correctly, but it does not apply to the problem. From what I can see, you are thinking that wr = Vb for the problem, right? A vector is just a quantity that has a direction. Velocity has a direction, and you're leaving it out. You can also add the vector of drag of the aircraft+drag from the wheel bearings, but we don't really need to make it that complicated. T>f which implies forward motion where T is thrust and f is the frictional forces. For something to be in static equilibrium, which is how you are looking at it, then the force vectors must equal zero. I.e. the sum of all forces must be equal to zero or Sigma. F = 0. But, since in reality Sigma F does not equal zero, then Sigma F = M*A where M is mass and A is acceleration. You are leaving important parts out.

Edited to add these: I didn't make them, but remembered seeing them. They show all forces at work which need to be included if you want to figure it out that way.

http://img150.imageshack.us/img150/6036/slide1nw9.jpg (http://imageshack.us)
http://img525.imageshack.us/img525/3272/slide2lw9.jpg (http://imageshack.us)
http://img525.imageshack.us/img525/3272/slide2lw9.b58091e156.jpg (http://g.imageshack.us/g.php?h=525&i=slide2lw9.jpg)
http://img156.imageshack.us/img156/2649/slide3sf9.jpg (http://imageshack.us)
http://img156.imageshack.us/img156/1976/freebodydiagrampage4ay2.jpg (http://imageshack.us)