Plane on a Treadmill?

[beaverretriever]

This was posted on another forum and it has gone about 40 pages so far. I cant believe people cant figure this out. Its scarry how dumb people are. :rolleyes:
A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?

[Phat Matt]

Depends

[beaverretriever]

Depends
No, it will fly... There is no question about it. :)

[Phat Matt]

http://www.jefflewis.net/graphics/aircraft/V-22_Osprey_in_helicopter_mode.jpg

[beaverretriever]

Either way it will take off. LOL :)

[BadKachina]

The wheels just roll so it doesn't matter how fast your spinning the conveyor belt, the wheels will just be moving faster. The plane will still fly, you'll just have more rolling resistance on take-off.

[racecar.hotshoe]

It wont fly theres no air going over the wings so theres no lift........ :rolleyes:

[Kachina26]

Yes.

[bonesfab]

no air speed, no lift off. it can go 200 mph on the tread mill but it still has no lift. unless you have one hell of a head wind.

[scooooter7]

How fast is the wind blowing??

[BadKachina]

It wont fly theres no air going over the wings so theres no lift........ :rolleyes:
What would stop the plane from moving foward? The thrust isn't created from the wheels so it doesn't matter how fast the ground is moving.

[beaverretriever]

Of course it will fly. The plane is producing thrust at the body, not the wheels. It doesnt matter whats going on at the wheels. If it was a car with wings, NO it wouldnt take off.
I hope you guys are kidding when you say it wont take off. :rolleyes:
http://www.focushacks.com/uploads/diagram.jpg

[Tom Brown]

The plane will crash without taking to the air but the runway will accelerate at twice it's normal rate, take off, exceed Vne, and then crash also.

[Cheap Thrills]

It wont fly theres no air going over the wings so theres no lift........ :rolleyes:
Ding ! no air no lift. air has to travel across the wing to provide lift period !
C.T. :wink:

[racecar.hotshoe]

Ding ! no air no lift. air has to travel across the wing to provide lift period !
C.T. :wink:
See!........... :crossx:

[Tom Brown]

If the plane had sufficient power, it might be able to take off with full brakes applied by stripping out the gears on the conveyor freewheeling the belt up to takeoff speed.

[Jetaholic]

A treadmill moving in the opposite direction of the plane, but at the same speed as the plane will cancel out all movement of the airplane, making it stand completely still. This will cancel out all airflow over the wings, thereby cancelling out all lift. All you end up with is the propwash...which does not produce lift...only thrust.
Now if the headwind is going the same speed as the airplane's Vr(speed of rotation), it will, however that would be one hell of a storm to fly into.

[upsman105]

Ding ! no air no lift. air has to travel across the wing to provide lift period !
C.T. :wink:
I concur....

[racecar.hotshoe]

If the plane had sufficient power, it might be able to take off with full brakes applied by stripping out the gears on the conveyor freewheeling the belt up to takeoff speed.
Doing a little reaching there Tom.............. :p

[Cheap Thrills]

The plane will crash without taking to the air but the runway will accelerate at twice it's normal rate, take off, exceed Vne, and then crash also.
Hey if he's a good pilot he could stab the toe brake on one side , spin the plane around and use the conveyor speed to sling it airborne. :D
C.T. :wink:

[racecar.hotshoe]

are we on page two yet? :crossx:

[Tom Brown]

A treadmill moving in the opposite direction of the plane, but at the same speed as the plane will cancel out all movement of the airplane, making it stand completely still.
No it won't. A plane doesn't use drive wheels to accelerate like a car does. It pushes against the air with a propeller or jet thrust making wheel speed almost irrelevant, within the limits of the bearings and wheels ability to withstand the centripetal force that comes from rotation.

[Sotally Tober]

Who cares?? It will, the jet engines are producing the thrust. Simple.

[racecar.hotshoe]

Hey if he's a good pilot he could stab the toe brake on one side , spin the plane around and use the conveyor speed to sling it airborne. :D
C.T. :wink:
unless hes in a tail dragger...........................

[Tom Brown]

Who cares??
Everyone who takes the time to post in this thread.

[vmjtc3]

This was posted on another forum and it has gone about 40 pages so far. I cant believe people cant figure this out. Its scarry how dumb people are. :rolleyes:
A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?
Yep it will take off, Conveyor tracks the planes speed therefore the plane is moving under it's own power. The wheels can spin either forwards or backwords makes no diff, the plane will move under it's own power and take off. :rolleyes:

[Cheap Thrills]

unless hes in a tail dragger...........................
Hmmm you're right . that may be the best groundloop ever ! Hold my beer,, lets try it :D
C.T. :wink:

[racecar.hotshoe]

Hmmm you're right . that may be the best groundloop ever ! Hold my beer,, lets try it :D
C.T. :wink:
Hit it! :coffeycup :D

[beaverretriever]

No it won't. A plane doesn't use drive wheels to accelerate like a car does. It pushes against the air with a propeller or jet thrust making wheel speed almost irrelevant, within the limits of the bearings and wheels ability to withstand the centripetal force that comes from rotation.
Is'nt crazy people dont understand that. :rollside:

[Tom Brown]

Is'nt crazy people dont understand that. :rollside:
Your graphic pretty much lays it out as clear as it could possibly be.
Speaking of laying out, I'm going to go back to imagining what it would be like to lay down with Pamala David.
Have a nice evening. :)

[racecar.hotshoe]

Your graphic pretty much lays it out.
Speaking of laying out, I'm going to go back to imagining what it would be like to lay down with Pamala David.
Have a nice evening. :)
Thats right Tom I knew you would be the one to leave your wingman! :cool:

[Tom Brown]

My wingman is in tight formation right now.
ttyl...

[racecar.hotshoe]

My wingman is in tight formation right now.
ttyl...
"TMI"

[deltaAce]

I can't see how they argued this to 40 pages. I seems clearly evident that the thrust from a prop or jet would propell an airframe forward irrespective of a conveyor belt runway.
Then again, we went 120 pages on "sunk the boat" & still have to ask when the boats gonna come up! :rolleyes:

[OCMerrill]

If "Later" posts then this could go 40 pages :)
Very complicated way of asking " If a Rooster laid an egg?".
The very second the plane is throttled up it will move forward....and it doesent matter if the wheels are spinning 1000 mph just as long as they are there to support the plane until "V2" is reached and the plane can take off.
Its an air speed thing.
If the plane is moving 100 knots then the wheels are moving 200 knots. Makes no difference. Need a runway length treadmill though.

[Ziggy]

I can't see how they argued this to 40 pages. I seems clearly evident that the thrust from a prop or jet would propell an airframe forward irrespective of a conveyor belt runway.
Then again, we went 120 pages on "sunk the boat" & still have to ask when the boats gonna come up! :rolleyes:
Seems to me no matter how much thrust is applied with the plane still on the ground it will not create groundspeed since the treadmill compensates for any forward motion of the wheels.
So as been said, no lift............she stays on the ground. :rolleyes:

[ahhell]

it would be the same if you were to secure the plane to the ground...no forward motion no lift off
but im no pilot

[ZBODaytona]

the answer was up top somwhere..ground speed would be X but airspeed would be say Y "something different"... if the plane needs 150 knots to take off then the wheels or ground speed would be at 300knots but the airspeed would still be 150knots....as stated above dosen't matter what the wheels are turing all that matters is that the plane is thrusting forward... if it was a car it wouldn't move but since the wheels on a plan just freespin (unless under breaking); the plane will still move....

[Sleek-Jet]

Yes, it will fly... the question never states the airplane stay stationary... just that the treadmill moves in the opposite direction as the wheel speed... the wheels will just be going twice as fast when the airplane lifts off.

[Jordy]

the question never states the airplane stay stationary... just that the treadmill moves in the opposite direction as the wheel speed
Hey Sleek, reread the question. It never mentions wheel speed it says PLANE speed and then moves the treadmill in the opposite direction accordingly, which would mean that the plane stays stationary, which means no lift, which means no takeoff. ;)
A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the PLANE'S
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?

[Sleek-Jet]

Hey Sleek, reread the question. It never mentions wheel speed it says PLANE speed and then moves the treadmill in the opposite direction accordingly, which would mean that the plane stays stationary, which means no lift, which means no takeoff. ;)
A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the PLANE'S
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?
Last time I checked, my airplane didn't care how fast it was traveling over the ground, it's all about the airspeed... and again, the question never states the airplane remains stationary...
If anyone wants to try this out... you can simulate this with a little rubber band powered airplane and a treadmill... Turn the treadmill up, wind the rubber band, set the airplane down on the treadmill and it will take off... :idea:

[sleekcraft137]

Just call Mythbusters and let them test it. :)

[Jordy]

Last time I checked, my airplane didn't care how fast it was traveling over the ground, it's all about the airspeed... and again, the question never states the airplane remains stationary...
OK, so if the treadmill is going exactly the same speed as the plane in the opposite direction, thereby cancelling out any air, or ground speed, it's not going to fly. Think of it as trying to walk up the down escalator at exactly the same speed as the steps, kind of like a Slinky. You'll be in the same place all day.

[CBadDad]

So what is the answer?
I have a feelin' this is gonnabe a long day...

[Halvecta]

So if some of you think that it will not fly.
Then reverse the treadmill. Will the plane now take off twice, three, four, etc. times faster? NO. The wheels are free from power.
If the plane needs hypothetically 80 mph to take off, then when the PLANE gets to 80 mph the plane takes off, and the wheels are going 160 mph.
If the brakes on the plane were stuck, and the plane had enough engine power, wouldn't it still be able to "skid" down the runway and take off (yes, that would take a whole lot of power).
What about the military jets taking off from aircraft cariers, when taking off into the wind, the wheels are not traveling any faster than when they would take off with the wind, it is just that into the wind gets them the lift (air over wing) quicker than with the wind.
I am just glad when I fly to Chicago next month, the pilots will not be concerned with the "wheel" speed, rather its air speed. Kinda like a GPS thing.
If your are thinking along the lines of surfing or skiing "up river". It is the water flow that is creating lift, not the speed of my body. Flying is just the opposite.
Blah, blah, blah, blah................................

[ZBODaytona]

OK, so if the treadmill is going exactly the same speed as the plane in the opposite direction, thereby cancelling out any air, or ground speed, it's not going to fly. Think of it as trying to walk up the down escalator at exactly the same speed as the steps, kind of like a Slinky. You'll be in the same place all day.
not the same...again the wheels are not providing the forward movement, if the wheels where providing the forward movement then yes it would be the same. again ground speed would be great..but like sleek said the plane doesn't care what the wheels are turning or what ground speed is....of course this all implies that the wheels can handle the increase in speed on them and the plane can over come the rolling resistance which i am assuming isn't that much...if the tread mill match the planes airspeed then the wheel speed will just keep increasing but the plane will continue to move forward.
if you want to try this out...take a model rocket mount it to a skate, then put it on a trade mill...gurantee the skate will move against the trade mill........or take a model airplane, take the wings off fire up the motor and put it on a tread mill i bet it will move forward....

[Ziggy]

Last time I checked, my airplane didn't care how fast it was traveling over the ground, it's all about the airspeed... and again, the question never states the airplane remains stationary...
If anyone wants to try this out... you can simulate this with a little rubber band powered airplane and a treadmill... Turn the treadmill up, wind the rubber band, set the airplane down on the treadmill and it will take off... :idea:
Wow, this is great. Me and Jordy agree on something :D:D:D
.
Sleek, it says the plane is "standing" on the moving runway. To get airspeed you first need groundspeed which the treadmill is preventing cuz it "instantly" compensates for ground motion.
.
Its like a car on a Dino.........haulin ass but going nowhere :)

[Jordy]

OK, so you super techy types are way overthinking this whole deal. I even did a Google search and found where people were figuring out friction from the bearings and rolling resistance from the tires. With that much free time they should be on ***boat figuring out the amount of lift needed to unsink Later's boat. :D :D :D
If the treadmill is matching the plane's speed in the opposite direction as the question states, the plane will be stationary. Explain how a stationary plane can gain airspeed, without some ridiculous amount of headwind.

[Cat & Mice]

This is a good one. the problem is that it states that the belt can match the planes ground speed which would be very hard to do. If it can then the belt would cause to much friction and the plane could not lift off. Plane needs to move through the air to create lift. Unless it has upward thrust.
Now if the belt was spinning so fast that it created enough head wind then maybe.
If the plane had engines that pushed air over the wings that would help
In Beaverretriever's great illistration there is a problem, the problem is that the forward thrust comes from air movement not a direct connection with the ground. If the belt can move fast enough then it does not matter how fast the engines move the air.
If you had the wheels of a plane chucked on the ground, not allowing movement then the forward thrust would have a very difficult time making the plane fly. I have had a small plane at full throttle with wheel chucks and it didn't take off!
So I would say No!
but I thought yes at first.
MP

[Halvecta]

"If the treadmill is matching the plane's speed in the opposite direction as the question states, the plane will be stationary. Explain how a stationary plane can gain airspeed, without some ridiculous amount of headwind.[/QUOTE]"
Because the wheels are simply going twice as fast as the plane itself is.

[Jordy]

Because the wheels are simply going twice as fast as the plane itself is.
Where does it say anything about the wheels???? It pretty much states that the treadmill is keeping the plane stationary by matching the plane's speed in the opposite direction. Not one time does it mention wheel speed.

[Sleek-Jet]

Wow, this is great. Me and Jordy agree on something :D:D:D
.
Sleek, it says the plane is "standing" on the moving runway. To get airspeed you first need groundspeed which the treadmill is preventing cuz it "instantly" compensates for ground motion.
.
Its like a car on a Dino.........haulin ass but going nowhere :)
But an airplane's engines do not drive the wheels, (that's the key difference)... they act on the airframe.
If I put an airplane on a wheel dyno, spin the dyno up to 60 mph, and give the airplane a boost of throttle... it'll taxi off the dyno...

[ZBODaytona]

OK, so you super techy types are way overthinking this whole deal. I even did a Google search and found where people were figuring out friction from the bearings and rolling resistance from the tires. With that much free time they should be on ***boat figuring out the amount of lift needed to unsink Later's boat. :D :D :D
If the treadmill is matching the plane's speed in the opposite direction as the question states, the plane will be stationary. Explain how a stationary plane can gain airspeed, without some ridiculous amount of headwind.
how can negate forward movement on something that the wheels just free spin on??? wouldn't the wheels just go faster and faster....

[Jordy]

how can negate forward movement on something that the wheels just free spin on??? wouldn't the wheels just go faster and faster....
How do you build a treadmill the length of a runway that can match a planes speed instantaneously???
WHERE DOES IT MENTION WHEELS?????????????
As I said, you guys are reading way too much into the question. The treadmill is keeping the plane stationary. How can you gain airspeed on a plane that isn't moving???

[Cat & Mice]

not the same...again the wheels are not providing the forward movement, if the wheels where providing the forward movement then yes it would be the same. again ground speed would be great..but like sleek said the plane doesn't care what the wheels are turning or what ground speed is....of course this all implies that the wheels can handle the increase in speed on them and the plane can over come the rolling resistance which i am assuming isn't that much...if the tread mill match the planes airspeed then the wheel speed will just keep increasing but the plane will continue to move forward.
if you want to try this out...take a model rocket mount it to a skate, then put it on a trade mill...gurantee the skate will move against the trade mill........or take a model airplane, take the wings off fire up the motor and put it on a tread mill i bet it will move forward....
That is unless the treadmill can match the thrust with friction. If the treadmill is able to speedup and move fast enough it could create enough friction to cancel out the forward thrust.
I just saw that Jordy and I agreed! :) :)

[ZBODaytona]

This was posted on another forum and it has gone about 40 pages so far. I cant believe people cant figure this out. Its scarry how dumb people are. :rolleyes:
A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?
doesn't say anything about the plane not moving or staying stationary..just that the runway can keep up with the airplanes speed..hence again the wheels would just move twice the speed of the plane.....cause they are free spining

[Jordy]

doesn't say anything about the plane not moving..
Sure it does "A plane is standing on a runway":
OK, so in all seriousness:
This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly
So back to the escalator. There is an escalator that will match your exact speed instantly but in the opposite direction. You run, it goes faster in the opposite direction, you walk it goes slower, in the opposite direction. Are you gaining any forward progress???

[ZBODaytona]

Sure it does "A plane is standing on a runway":
OK, so in all seriousness:
So back to the escalator. There is an escalator that will match your exact speed instantly but in the opposite direction. You run, it goes faster in the opposite direction, you walk it goes slower, in the opposite direction. Are you gaining any forward progress???
no i am not..but because my feet (the wheels) are what move me forward...now lets say it is a moving side walk..i have rollerskates on...now i have an outside power source (jet motor, rocket engine on the skates) that doesn't rely on the ground to move me...i will move forward...even if it moves faster..my wheels will just turn faster...so my body speed (air speed) would be lets say 5 mph but my wheel speed would be 10 mph....again as long as the friction created doesn't over come my thrust...all this being hypothetical..

[Cat & Mice]

Ok wait!
"A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly."
It does not say it tracks the wheels speed or ground speed.
I change my mind again :rolleyes:
If the plane gets any speed then it does not matter what the ground does.
Sorry Jordy! :p
Actually I have no fricken idea :mad: :cry:
Pyle Out!!

[Ziggy]

Its so easy even a Caveman can do it :p

[Jordy]

no i am not..but because my feet (the wheels) are what move me forward...now lets say it is a moving side walk..i have rollerskates on...now i have an outside power source (jet motor, rocket engine on the skates) that doesn't rely on the ground to move me...i will move forward...even if it moves faster..my wheels will just turn faster...so my body speed (air speed) would be lets say 5 mph but my wheel speed would be 10 mph....again as long as the friction created doesn't over come my thrust...all this being hypothetical..
Still hung up on the wheels huh??? :notam:

[Ziggy]

Ok wait!
"A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly."
It does not say it tracks the wheels speed or ground speed.
I change my mind again :rolleyes:
If the plane gets any speed then it does not matter what the ground does.
Sorry Jordy! :p
Actually I have no fricken idea :mad: :cry:
Pyle Out!!
Well maybe there's no wheels on the plane....LOL :idea:
.
Forward motion = lift
Conveyor belt consensates any forward motion= no lift

[ZBODaytona]

Still hung up on the wheels huh??? :notam:
your right it did say standing.....

[Jordy]

It does not say it tracks the wheels speed or ground speed.
Probably because 99.9% of the people who are asked the question don't know the difference because they aren't pilots or geeks or geeky pilots. Plane speed is plane speed to the average Joe. They don't need to know about SOG, airspeed, wheel speed, or where to buy speed for that all night flight. :D :D :D

[Cat & Mice]

"This conveyor has a control system"
If the control system runs on windows then it will crash and the plane will fly.
Did I win? :)
MP

[Sleek-Jet]

Airplanes travel through the air... so if the treadmill is somehow able to bend the laws of physics and make the air move in the opposite direction... the airplane will still take off... unless we're in a vacuum, and then it won't because the wings won't develope any lift.
If this was true, all airplanes would have to avoid flying over LA Fitness... :D

[HM]

Alright you mental midgets, you probably have no idea that the 3 legged hairy angry midget has a B.S. in Physics and Mechanical engineering...did ya?
The plane takes off. The question states the conveyor will go in the exact speed of the "plane" in the opposite direction. So, if the plane is moving at 100 knots, then the conveyor will go the other way at 100 knots. The wheels will be going 200 knots. Regardless of what drives the plane, the plane will take off - even if the wheels were the force moving the plane forward as it states "plane speed" not "Wheel speed". Again, if the conveyor moves in the opposite direction at the exact speed of the "plane" the wheels would mearly have to get to a speed of 200 knots to propel the plane forward at 100 knots. So those of you that think that because the wheels are not driving that it can move forward are also a taco short of a full combo platter. It is very simple...the wheels will be traveling twice the speed of the plane speed.
Now, if the question had stated that the conveyor would go in the opposite and exact speed of the "wheels", it does not matter what propels it, as the speed of the wheels would be moving towards and infinite speed and there is no way to have a wheel that could handle the heat from the friction of that kind of speed and you would have mechanical failure of the wheels - or anything else that was in contact with the conveyor.
Now I know why logic fails so much on hot boat. If you think the plane does not take off, I will send over the shortbus to your home to take you back to school. And the shortbus is coming for those that argued that because the wheels were not pushing the plane was why it would take off.
This is not up for debate. It is a simple math question that many of you are failing.

[Cat & Mice]

Airplanes travel through the air... so if the treadmill is somehow able to bend the laws of physics and make the air move in the opposite direction... the airplane will still take off... unless we're in a vacuum, and then it won't because the wings won't develope any lift.
If this was true, all airplanes would have to avoid flying over LA Fitness... :D
Thats pretty funny! :D

[ahhell]

How does a stationary plane take off ????????
:argue:

[Cat & Mice]

Alright you mental midgets, you probably have no idea that the 3 legged hairy angry midget has a B.S. in Physics and Mechanical engineering...did ya?
The plane takes off. The question states the conveyor will go in the exact speed of the "plane" in the opposite direction. So, if the plane is moving at 100 knots, then the conveyor will go the other way at 100 knots. The wheels will be going 200 knots. Regardless of what drives the plane, the plane will take off - even if the wheels were the force moving the plane forward as it states "plane speed" not "Wheel speed". Again, if the conveyor moves in the opposite direction at the exact speed of the "plane" the wheels would mearly have to get to a speed of 200 knots to propel the plane forward at 100 knots. So those of you that think that because the wheels are not driving that it can move forward are also a taco short of a full combo platter. It is very simple...the wheels will be traveling twice the speed of the plane speed.
Now, if the question had stated that the conveyor would go in the opposite and exact speed of the "wheels", it does not matter what propels it, as the speed of the wheels would be moving towards and infinite speed and there is no way to have a wheel that could handle the heat from the friction of that kind of speed and you would have mechanical failure of the wheels - or anything else that was in contact with the conveyor.
Now I know why logic fails so much on hot boat. If you think the plane does not take off, I will send over the shortbus to your home to take you back to school. And the shortbus is coming for those that argued that because the wheels were not pushing the plane was why it would take off.
This is not up for debate. It is a simple math question that many of you are failing.
OK I hate to say it but I think Holy wins. He was able to explain in one post.
Go ahead and tell him what he won!
MP

[Jordy]

Airplanes travel through the air...
But to do that they have to generate lift. You still haven't explained how a plane that isn't moving can do that. Perhaps by bending the laws of physics??? :idea:
I know, it's a trick question, the plane is actually a Harrier and can VTO right??? :notam:

[Infomaniac]

LOL
Ground speed has nothing to do with flight.
If you can get the air to move like a treadmill it will fly.
DUH !!

[Jordy]

How does a stationary plane take off ????????
:argue:
Bingo. Some people just apparently like to overthink simple questions. :D
Hey, I know, whether or not the plane takes off depends on how many hot stewardesses are on the plane and how big their implants are. :D

[Sleek-Jet]

Alright you mental midgets, you probably have no idea that the 3 legged hairy angry midget has a B.S. in Physics and Mechanical engineering...did ya?
The plane takes off. The question states the conveyor will go in the exact speed of the "plane" in the opposite direction. So, if the plane is moving at 100 knots, then the conveyor will go the other way at 100 knots. The wheels will be going 200 knots. Regardless of what drives the plane, the plane will take off - even if the wheels were the force moving the plane forward as it states "plane speed" not "Wheel speed". Again, if the conveyor moves in the opposite direction at the exact speed of the "plane" the wheels would mearly have to get to a speed of 200 knots to propel the plane forward at 100 knots. So those of you that think that because the wheels are not driving that it can move forward are also a taco short of a full combo platter. It is very simple...the wheels will be traveling twice the speed of the plane speed.
Now, if the question had stated that the conveyor would go in the opposite and exact speed of the "wheels", it does not matter what propels it, as the speed of the wheels would be moving towards and infinite speed and there is no way to have a wheel that could handle the heat from the friction of that kind of speed and you would have mechanical failure of the wheels - or anything else that was in contact with the conveyor.
Now I know why logic fails so much on hot boat. If you think the plane does not take off, I will send over the shortbus to your home to take you back to school. And the shortbus is coming for those that argued that because the wheels were not pushing the plane was why it would take off.
This is not up for debate. It is a simple math question that many of you are failing.
What's knot???
I like Tacos... :D
I never knew Midget's are so articulate. :idea:

[MudPumper]

Does the plane have fuel and have they completed their pre-flight check list and walk around????? Have they been cleared for take off by the tower???
You guys kill me.....Don't make me start the debate about if a Jetboat is propelled by the trust of the water coming out the back or by getting pulled through the water by the impeller. :crossx:

[Infomaniac]

But to do that they have to generate lift. You still haven't explained how a plane that isn't moving can do that. Perhaps by bending the laws of physics??? :idea:
I know, it's a trick question, the plane is actually a Harrier and can VTO right??? :notam:
I havent read every post. so........
Air flow over and under the wing generates lift. A very strong wind (duh) will make a stationary plane fly. Thats one reason you tie them down when parked.
Bernouli's principal is how they fly. The cambered top surface of the wing creates a low pressure when air flows over it. The relatively flat bottom surface (compared to the top) of the wing allows the air flow to remain at static pressure. The difference of higher pressure under the wing and lower pressure on top of the wing creates lift.
does not matter what causes the aif flow. Wind by itself or fwd motion of the plane. or both.

[Jordy]

I havent read every post. so........
Air flow over and under the wing generates lift. A very strong wing will make a stationary plane fly. Thats one reason you tie them down when parked.
Bernouli's principal is how they fly. The cambered top surface of the wing creates a low pressure when air flows over it. The relatively flat bottom surface (compared to the top) of the wing allows the air flow to remain at static pressure. The difference of higher pressure under the wing and lower pressure on top of the wing creates lift.
does not matter what causes the aif flow. Wind by itself or fwd motion of the plane. or both.
I took physics too and understand the principles of flight, lift, drag, etc. However, I've yet to see anyone explain how a stationary plane can generate lift.
If the treadmill is matching the planes speed in the opposite direction it won't move, and if it's not moving, and there aren't hurricane force winds, it's not going to take off. The question doesn't ask anything about wheel speed, wind speed, fuel levels, scenery or anything else. ;)

[Infomaniac]

I took physics too and understand the principles of flight, lift, drag, etc. However, I've yet to see anyone explain how a stationary plane can generate lift.
If the treadmill is matching the planes speed in the opposite direction it won't move, and if it's not moving, and there aren't hurricane force winds, it's not going to take off. The question doesn't ask anything about wheel speed, wind speed, fuel levels, scenery or anything else. ;)
No one is going to explain how a stationary plane is going to generate lift with a treadmill. it cant happen.
unless they get lucky and an enormous gust oif wind happens at the same time.
LOL

[Ziggy]

One train leaves New York at 6am traveling west at an average speed of 80mph.....
Another leaves Los Angeles at the same time and traveling at the same speed, where will they meet?

[HM]

I took physics too and understand the principles of flight, lift, drag, etc. However, I've yet to see anyone explain how a stationary plane can generate lift.
Very simple...the PLANE is NOT stationary. You obviously didn't read my post. The conveyor moves in relation to the plane speed - not the wheel speed. Don't worry kid, Einstein failed math too. Nothing to do with lift here. Very simple...the wheels travel at twice the speed. The Shortbus is coming to Phoenix first. :D

[Ziggy]

Very simple...the PLANE is NOT stationary. You obviously didn't read my post. The conveyor moves in relation to the plane speed - not the wheel speed. Don't worry kid, Einstein failed math too. Nothing to do with lift here. Very simple...the wheels travel at twice the speed. The Shortbus is coming to Phoenix first. :D
This thread is worthless without pics :p

[Jordy]

Very simple...the PLANE is NOT stationary.
So how can a plane be moving if the treadmill is matching the plane's speed in the opposite direction exactly and instantaneously??? They cancel each other out Einey. ;)
You obviously didn't read my post. The conveyor moves in relation to the plane speed - not the wheel speed.
Exactly, in the OPPOSITE direction. Go back to the escalator example, it might be easier for you to understand.
Very simple...the wheels travel at twice the speed.
The wheels could travel 11,000 400 37 dozen times the speed, but if the plane isn't moving it's not going to take off. Where does it say anything about the plane's wheels Mighty Might???
The Shortbus is coming to Phoenix first. :D
From what I can tell it doesn't need to leave Cali because it's going to be full. Sleek could just fly over but his plane is on the treadmill and won't take off so he's really puzzled now. :D :D :D

[Jordy]

No one is going to explain how a stationary plane is going to generate lift with a treadmill. it cant happen.
Bingo, so the plane isn't going to take off. ;)

[thumbs]

It wont fly theres no air going over the wings so theres no lift........ :rolleyes:
I concur.

[CHEETAH24]

I say the firestone tire overheats and has a blowout, then ends up spinning out of control all over the tarmac.

[racecar.hotshoe]

it would work with this one........The Harrier is bad a$$
http://www.airforce-technology.com/projects/fa2/images/seaharrier4.jpg

[Jordy]

it would work with this one........The Harrier is bad a$$
Refer to post #71. :D

[CHEETAH24]

Who says the engines are running anyway? A plane sitting on the treadmill would indicate the engines are off. So no liftoff.

[racecar.hotshoe]

Refer to post #71. :D
Posts without pics dont count..... :coffeycup :D

[deltaAce]

Let me try once more,
The trust produced by a prop or jet overcomes ambient air to produce the forward motion. Reguardless of what force a treadmill exerts to spin the tires, the extreem force of the propulsion device pushing against stationary air will propell an airframe forward in relation to the stationary air, not the conveyor. For every action there is an equall reaction, thus the propullsion from thrust against the air provides forward motion. Will a sea plane take off agaist a fast river current? If the thrust will overcome the drag of the water against the pontoons!

[AirtimeLavey]

So, I thought the wheels were attached to the plane. If they are attached to the plane, how can they travel at twice the speed of the plane?
You're not talking rotation speed of the wheels, as that would not be only twice the speed of the plane, it would be much more. The question implies ground speed w/the comment of "plane speed" while standing on the runway.
Having said that, I believe once power is applied, it will fly as the wheels rotation won't affect it's ultimate ability to takeoff, and the thrust provided creates movement/airspeed that overcomes whatever contact the wheels have with the ground/gravity.
Where do I get in line for the bus? :mix: :messedup:

[Jordy]

Let me try once more,
Me too... WHO SAID ANYTHING ABOUT WHEELS??? Hell, for all we know the plane doesn't even have wheels.
The trust produced by a prop or jet overcomes ambient air to produce the forward motion. Reguardless of what force a treadmill exerts to spin the tires, the extreem force of the propulsion device pushing against stationary air will propell an airframe forward in relation to the stationary air, not the conveyor.
But the treadmill is matching the plane's exact speed in the OPPOSITE direction, thereby making the plane stationary. As was pointed out stationary planes don't generate lift. ;)
For every action there is an equall reaction, thus the propullsion from thrust against the air provides forward motion.
It's an equal and opposite reaction, of which the treadmill is the opposite reaction, keeping the plane stationary, and thus, on the ground. ;)
Will a sea plane take off agaist a fast river current. If the thrust will overcome the drag of the water against the pontoons!
OK, say the river can match EXACTLY and instantaneously, in the opposite direction, the speed of the sea plane. Will it take off??? No, it's going to stay in the same spot. ;)

[AirtimeLavey]

Let me try once more,
The trust produced by a prop or jet overcomes ambient air to produce the forward motion. Reguardless of what force a treadmill exerts to spin the tires, the extreem force of the propulsion device pushing against stationary air will propell an airframe forward in relation to the stationary air, not the conveyor. For every action there is an equall reaction, thus the propullsion from thrust against the air provides forward motion. Will a sea plane take off agaist a fast river current? If the thrust will overcome the drag of the water against the pontoons!
This is best explanation.... :boxed:

[CBadDad]

If it will fly, then why don't airports have treadmills instead of runways?

[Ziggy]

Let me try once more,
The trust produced by a prop or jet overcomes ambient air to produce the forward motion. Reguardless of what force a treadmill exerts to spin the tires, the extreem force of the propulsion device pushing against stationary air will propell an airframe forward in relation to the stationary air, not the conveyor. For every action there is an equall reaction, thus the propullsion from thrust against the air provides forward motion. Will a sea plane take off agaist a fast river current? If the thrust will overcome the drag of the water against the pontoons!Only if the forward motion overcomes the speed of the waterflow........in this equation its stated the the conveyor(or waterflow) equals the speed of the plane, in other words its stays in the same place and doesn't move forward.
.
Consider a jetboat(or any for that fact) and how much throttle is required just to stay in one spot.

[Jordy]

This is best explanation.... :boxed:
Too bad it's incorrect based upon the information given in the question. ;)

[AirtimeLavey]

OK, say the river can match EXACTLY and instantaneously, in the opposite direction, the speed of the sea plane. Will it take off??? No, it's going to stay in the same spot. ;)
This is different, because the pontoons are fixed, and no compensation for the water flow, whereas the wheels cancel out reverse direction of the treadmill.
CHEETAH24 I say the firestone tire overheats and has a blowout, then ends up spinning out of control all over the tarmac.
Don't know why airports don't have treamills, but now I know why my boat trailer will never fly.

[Jordy]

whereas the wheels cancel out reverse direction of the treadmill.
OK, once again:
WHERE DOES IT MENTION WHEELS???????
It says the treadmill matches the plane's speed in the opposite direction. Show me where wheels are even mentioned. :idea:

[deltaAce]

But the treadmill is matching the plane's exact speed in the OPPOSITE direction, thereby making the plane stationary. As was pointed out stationary planes don't generate lift. ;)
It's an equal and opposite reaction, of which the treadmill is the opposite reaction, keeping the plane stationary, and thus, on the ground. ;)
The treadmill is spinning the wheels backward, but the extreem thrust against ambient air is still generating forward motion on the airframe.
The equal and opposite reaction is the thrust against ambient air.
It's easy to see that a car would remain stationary on a conveyor because it is driven by the wheels, but a plane is propelled by the thrust exerted against the atomosphere.

[Jbb]

Rd Sux!

[Biglue]

HB Mythbusters???? :idea: :D

[AirtimeLavey]

OK, once again:
WHERE DOES IT MENTION WHEELS???????
It says the treadmill matches the plane's speed in the opposite direction. Show me where wheels are even mentioned. :idea:
Lol...Ok, with that logic, then where does it say the plane has wings? or an engine? or a pilot? Most planes have wheels, except maybe that rocket plane from WWII, or those suicide gliders they used to deliver troops.
Ok, gimme my dork card, now, damn it! :boxed: :rollside:

[Jordy]

So it seems as though this is more of a question regarding reading comprehension than the acutal physics of flight. So lets try again:
A plane is standing on a runway that can move (like a giant conveyor belt).
This conveyor has a control system that tracks the plane's speed and tunes the speed of the conveyor to be exactly the same (but in the opposite direction) instantly.
Will the plane be able to take off?
I bolded the important part so it wouldn't be missed.
Now I don't know about anyone else, but all I'm seeing is that the conveyor is going to cancel out the speed of the plane. No mention of wheel speed, ground speed, speed over ground, headwinds, big titted stewardess' or the pilot's BAC.
The treadmill is spinning the wheels backward, but the extreem thrust against ambient air is still generating forward motion on the airframe.
Still stuck on the wheels I see. It doesn't even say the plane has wheels. You're making assumptions here that aren't stated and then overthinking the answer.
The equal and opposite reaction is the thrust against ambient air.
The way I see it, based upon how the question is worded and what we know, is that the two equal and opposite forces are the planes speed and the treadmill, which effectively cancel each other out, leaving the plane stationary on the ground.
It's easy to see that a car would remain stationary on a conveyor because it is driven by the wheels, but a plane is propelled by the thrust exerted against the atomosphere.
I don't give a shit if the wheels are 28" spinners, they're not relevent to the question as it's worded.

[Jordy]

This thread is at least still better than the sunk the boat thread, for now anyway. ;)
You can do a google search of this question and find a million different answers with people trying to offer solutions based up on rolling resistance, elevation, flap settings, ambient temperature, wind speed, thrust of the engines, jet or piston, wing surface area, payload, lift coefficient, and on and on and on. Yes, all that stuff comes into play with flight, however, none of that is a factor in the question the way it's worded. :notam:
The simple fact is, the plane isn't moving and a stationary plane, based upon the facts we know, won't generate lift. Lesson over. Tip your waitresses. :D
Now Midget Boy, about that short bus... :D

[Sleek-Jet]

I don't give a shit if the wheels are 28" spinners, they're not relevent to the question as it's worded.
They be spinnen when I's stopped... and the ain't spinnen when I's movin... :D Look at 'em... theyz spinnen... theyz spinnen...

[CornWater]

Wheels shmeels.... It does'nt matter.. The speed of the conveyor is irrelevant. If plane air speed needs to be 200mph (arbitrarily) to take off, conveyor will be moving 200mph in other direction. Most def. will take off...

[AirtimeLavey]

So it seems as though this is more of a question regarding reading comprehension than the acutal physics of flight. So lets try again:
Now I don't know about anyone else, but all I'm seeing is that the conveyor is going to cancel out the speed of the plane. No mention of wheel speed, ground speed, speed over ground, headwinds, big titted stewardess' or the pilot's BAC.
Still stuck on the wheels I see. It doesn't even say the plane has wheels. You're making assumptions here that aren't stated and then overthinking the answer.
The way I see it, based upon how the question is worded and what we know, is that the two equal and opposite forces are the planes speed and the treadmill, which effectively cancel each other out, leaving the plane stationary on the ground.
I don't give a shit if the wheels are 28" spinners, they're not relevent to the question as it's worded.
The.....wheels'.....rotation.....cancel .....out....the.....treadmill. So,....we're....left....with....thrust.....from... ..the....engine....creating....forward .....movement. I could be wrong, though. :crossx:
The plane won't fly with spinners, as no matter how fast the tires rotate, the wheels appear stationary. They cancel each other out. :idea: :boxed:

[CBadDad]

A new B.S. thread that isn't about Later.
This is what HB is all about.
:cool:

[Jordy]

Wheels shmeels.... It does'nt matter..
Exactly. Finally someone gets that part of it. ;)
The speed of the conveyor is irrelevant.
Wrong, that's one of 2 things that are relevant in this equation, the other being plane speed.
If plane air speed needs to be 200mph (arbitrarily) to take off, conveyor will be moving 200mph in other direction.
OK, so it's been a while since I've taken physics, but this is pretty simple so I'll give it a shot.
We'll call your 200mph plane speed +200. We'll call the treadmill's 200mph speed in the opposite direction -200.
Now we take +200 and add it to -200 and come up with 0 for an overall speed. The plane isn't moving.
Most def. will take off...
How??? Even the people who are hung up on the wheel thing can agree that a plane that isn't moving doesn't generate lift and won't fly. ;)

[BajaMike]

This thread is at least still better than the sunk the boat thread, for now anyway. ;)
The simple fact is, the plane isn't moving and a stationary plane, based upon the facts we know, won't generate lift. Lesson over. Tip your waitresses. :D
Now Midget Boy, about that short bus... :D
Jordy is right.....you can only use the information you are given.... :cool:
"A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?"
The "plane is standing on the runway". "Standing" implies a stationary airplane....it says nothing about thrust or movement......the plane is not moving, so the "speed of the conveyor.....is exactly the same" as the airplane......0 miles per hour! :idea: Not likely to take off at 0 miles per hour.
You've got to use the information given and only that information!
:cool:

[Tom Brown]

Now we take +200 and add it to -200 and come up with 0 for an overall speed. The plane isn't moving.
... and if I take your 0 result and add 1.59 to it, you get the cost of a McRib sandwich. :idea:

[CornWater]

OK, so it's been a while since I've taken physics, but this is pretty simple so I'll give it a shot.
We'll call your 200mph plane speed +200. We'll call the treadmill's 200mph speed in the opposite direction -200.
Now we take +200 and add it to -200 and come up with 0 for an overall speed. The plane isn't moving.
Well it has been a lil' while since I've had dynamics, but it is simply reference velocity. So by that theory, does it mean that two trains passing each other at 50mph in opposited directions have on overall velocity of 0mph??? No.

[Jordy]

Jordy is right.....you can only use the information you are given.... :cool:
"A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?"
The "plane is standing on the runway". "Standing" implies a stationary airplane....it says nothing about thrust or movement......the plane is not moving, so the "speed of the conveyor.....is exactly the same" as the airplane......0 miles per hour! :idea: Not likely to take off at 0 miles per hour.
You've got to use the information given and only that information!
:cool:
Bingo. But to even go a step further and go under the assumption that the plane is going to try and take off under power, the tread mill speed will cancel out the plane speed, leaving it standing on the runway, not taking off. ;)
I'll be here all week. Try the veal!!! :D :D

[Jordy]

So by that theory, does it mean that two trains passing each other at 50mph in opposited directions have on overall velocity of 0mph??? No.
No, because they're separate forces not acting upon each other like the treadmill and the plane are. ;)

[AirtimeLavey]

... and if I take your 0 result and add 1.59 to it, you get the cost of a McRib sandwich. :idea:
So how do they get it shaped like that, anyway? :idea:

[Tom Brown]

So how do they get it shaped like that, anyway? :idea:
They use a CNC rib press.

[beaverretriever]

... and if I take your 0 result and add 1.59 to it, you get the cost of a McRib sandwich. :idea:
Boy do I have the good post? Treadmills and McRibs.. :D

[BajaMike]

I can't see how they argued this to 40 pages. I seems clearly evident that the thrust from a prop or jet would propell an airframe forward irrespective of a conveyor belt runway.
:rolleyes:
If that theory worked, they could use conveyor belts to test aircraft aerodynamics instead of wind tunnels......thrust doen't create lift, air over the wings does (except in a rocket, but those go straight up, so the conveyor wouldn't matter). :idea:
Plus you are reading too much into it....the airplane is "standing" on the runway!
:rollside:

[CBadDad]

Where's the three legged midget when we need him to straighten us all out now?

[1980Cougar]

OK, so it's been a while since I've taken physics, but this is pretty simple so I'll give it a shot.
We'll call your 200mph plane speed +200. We'll call the treadmill's 200mph speed in the opposite direction -200.
Now we take +200 and add it to -200 and come up with 0 for an overall speed. The plane isn't moving.
The plane will fly, regardless of the speed of the treadmill.
Lets assume that our plane can fly 200 mph.
Lets fly the plane over the treadmill with the landing gear up.
The treadmill is moving in the opposite direction at 200 mph.
Our pilot lowers his wheels and sets the plane onto them.
The plane is still moving at 200 mph.
The planes wheels are turning as though the plane is going 400 mph over a normal runway.
The plane will continue flying.
If our planes engines can create thrust for 200 mph, then our plane can take off of a treadmill moving in the opposite direction.
No problem! :)

[HEDJUG]

-Air speed is not effected. (the plane uses thrust to create speed, not friction from the ground like a car or person does)
-Ground speed (by GPS) is not effected.
-Thrust is not effected.
-Acceleration is not effected.
-Wheel speed is effected. Thats it.
The only force that will effect the plane is the extra friction on the wheel bearings & the extra rolling resistance from the wheels spinning 2x faster than usual. That is in no way enough friction to stop the plane from taking off. Assuming the wheel bearings & the tires could handle the speed, that tread mill could go 4x, 6x, 8x, 10x... faster in the opposite direction & the plance would take off.
The plane will take off. Its maximum ground speed may only slow by a tiny-tiny-tiny factor , but not enough to stop the plane.

[Tom Brown]

Plus you are reading too much into it....the airplane is "standing" on the runway!
Have a McRib sandwich.

[Desert Rat]

It wont fly theres no air going over the wings so theres no lift........ :rolleyes:
Bingo
aircraft need air moving over and under the wing to create LIFT, spinning the wheels won't do it

[CornWater]

I did'nt mean to imply that the wheels were irrelevant, only that they provide no forward thrust, as in a car. The thrust is solely a result of propulsion from either a propellor or turbine. The only difference is that the wheels wheel now move twice as fast as the plane due to the conveyor in the opposite direction.

[racecar.hotshoe]

The plane will fly, regardless of the speed of the treadmill.
Lets assume that our plane can fly 200 mph.
Lets fly the plane over the treadmill with the landing gear up.
The treadmill is moving in the opposite direction at 200 mph.
Our pilot lowers his wheels and sets the plane onto them.
The plane is still moving at 200 mph.
The planes wheels are turning as though the plane is going 400 mph over a normal runway.
The plane will continue flying.
If our planes engines can create thrust for 200 mph, then our plane can take off of a treadmill moving in the opposite direction.
No problem! :)
"wrong"
http://www.***boat.com/image_center/data/520/1917M_m2.JPG

[YeLLowBoaT]

A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?
I remember in ground school being asked this Q, but it was worded alot better. :rolleyes: That Q was ez... it was yes
This one, do to the way its worded is not as ez( the choice of phrasing and wording are very poor). Speed is all relative too the observer. So it all depends on the observer. :) Thats going a little too deep...
So rather or not it will take off depends on, what speed you use and who is seeing it. :crossx:

[HEDJUG]

Bingo
aircraft need air moving over and under the wing to create LIFT, spinning the wheels won't do it
You boys are missing the point. Lets make is very simple.
The thrust from the engines move the plane foward. The wheels spin faster as the speed increases. If the ground decides to move in the opposite direction of the plane, at any speed, the plane will continue to move forward at the same rate. The wind across the wings will not be effected at all. The plane will be able to accelerate at will.

[ZBODaytona]

the way i read the question is that a plane is on a treadmill, if the planes speed was to change the tread mill would go the other way in that speed..then it ask can the plane take off. the answer is yes the plane can take off in my way of thinking since i am hung on the wheels...
but i also see what jordy's is saying as well.
i do agree this is more fun the sunk boat thread, and i get to finally help my post count yeah...if that matters

[R.A.D.man]

Hey, anyone else remember this thread?
http://www2.***boat.com/forums/showthread.php?t=99838&highlight=treadmill

[Tom Brown]

How come nobody has started a "Sunk the Plane" thread?

[ratso]

This was posted on another forum and it has gone about 40 pages so far. I cant believe people cant figure this out. Its scarry how dumb people are. :rolleyes:
A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?
NO!

[AirtimeLavey]

How come nobody has started a "Sunk the Plane" thread?
LMAO...the question didn't say anything about water... :rolleyes:
But can a plane sink while it's sitting on a runway that's also a conveyor belt? Will the McRib float when the plane sinks?

[ZBODaytona]

aww that one only made 5 pages..6 here...

[seanv]

has anyone posted "rd sux" yet??? :rolleyes:
the plane in a stationary state will not take off unles later is the pilot and he has enough in donations to pay for the fuel. it will end in tradgedy when this one goes down though...

[Tom Brown]

Will the McRib float when the plane sinks?
I don't think a McRib will float on anything.

[Jbb]

has anyone posted "rd sux" yet??? :rolleyes:
the plane in a stationary state will not take off unles later is the pilot and he has enough in donations to pay for the fuel. it will end in tradgedy when this one goes down though...
Post #100.. :rolleyes: ..Please pay attention...

[racecar.hotshoe]

I don't think a McRib will float on anything.
I think your wrong.......Go eat one and tomorrow you can watch it float :p

[HM]

Here is an interesting question for Jordy...How does the conveyor move if the plane does not move? The plane moves relative to the ground. The conveyor moves relative to the plane. The speed between the conveyor and the plane is 2x's that of the plane to ground speed. The conveyor is only on the runway.
This is a reference riddle. And Jordy failed. ;)

[AirtimeLavey]

Does anyone know the location of the plane?

[Jbb]

I think your wrong.......Go eat one and tomorrow you can watch it float :p
Uggh...dont give him any ideas......tomorrow you will wake up to a stage 3 Mcrib floater......still pics and video... :p

[racecar.hotshoe]

:p Uggh...dont give him any ideas......tomorrow you will wake up to a stage 3 Mcrib floater......still pics amd video... :p

[seanv]

Does anyone know the location of the plane?
somewhere around lake piru... :rolleyes:

[UltraClean]

Just call Mythbusters and let them test it. :)
LOL those guys are too much!!! they frequent the bars in San Francisco ...have seen them from time to time :mad: ....in my opinion though the plane would take off... :argue:

[AZJD]

This was posted on another forum and it has gone about 40 pages so far. I cant believe people cant figure this out. Its scarry how dumb people are. :rolleyes:
A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?
THE ANSWER IS NO!!!!!!!!!!!!!!!!!!!!!!!!!!! This is funny stuff..........what does it take for a plane to become airborn? LIFT! How is LIFT attained? Head wind! If the plane is not able to achieve forward momentum, no head wind is generated, therefore there will be no lift achieved!

[Tom Brown]

THE ANSWER IS NO!!!!!!!!!!!!!!!!!!!!!!!!!!!!
I think you're incorrect!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!

[HEDJUG]

THE ANSWER IS NO!!!!!!!!!!!!!!!!!!!!!!!!!!! This is funny stuff..........what does it take for a plane to become airborn? LIFT! How is LIFT attained? Head wind! If the plane is not able to achieve forward momentum, no head wind is generated, therefore there will be no lift achieved!
O.K. genius. Tell us why the plane won't be able to achieve headwind.

[AZJD]

I think you're incorrect!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!
It's a good thing you are entitled to your opinion around here! :)

[CBadDad]

O.K. genius. Tell us why the plane won't be able to achieve headwind.
Uh, because it's not moving.

[SB]

You boys are missing the point. Lets make is very simple.
The thrust from the engines move the plane foward. The wheels spin faster as the speed increases. If the ground decides to move in the opposite direction of the plane, at any speed, the plane will continue to move forward at the same rate. The wind across the wings will not be effected at all. The plane will be able to accelerate at will.
I do see your point, but I don't agree.
When I run on a treadmill, there is no wind in my face.
The plane is not moving through the air, no lift under the wings.

[AZJD]

O.K. genius. Tell us why the plane won't be able to achieve headwind.
Because it is on a treadmill that is countering any forward movement by matching its wheelspeed, or attempt at generating groundspeed!

[AZJD]

I do see your point, but I don't agree.
When I run on a treadmill, there is no wind in my face.
The plane is not moving through the air, no lift under the wings.
Just to set the record straight here, lift is created at the top of the wing. The wing does not ride on a cusion of air, a lift is created the pulls the top of the wing!

[ratso]

O.K. genius. Tell us why the plane won't be able to achieve headwind.
lol... maybe Myth Busters can try this. :idea:

[Tom Brown]

It's a good thing you are entitled to your opinion around here! :)
Many would argue that. :D

[Tom Brown]

Because it is on a treadmill that is countering any forward movement by matching its wheelspeed, or attempt at generating groundspeed!
The treadmill will not counter forward movement of the plane. That is the whole point of aircraft landing gear.

[SB]

Furthermore, if this were possible, the Navy would not have to build aircraft carriers with long runways. The Navy could just build a ****in treadmill on the deck, and let the plane takeoff.
Well ok, they'd still have to land. But I suppose you folks think the plane could land on a treadmill too.

[AZJD]

lol... maybe Myth Busters can try this. :idea:
They wouldn't waste the production $$$$$$$$$$$$$$, this is the dumbest arguement I have ever heard!
If you want to put a huge fan in front of it, (which I believe has been proposed) to generate or duplicate headwind, it may work!

[SB]

Just to set the record straight here, lift is created at the top of the wing. The wing does not ride on a cusion of air, a lift is created the pulls the top of the wing!
Excuse me, this is correct.

[Tom Brown]

Just to set the record straight here, lift is created at the top of the wing. The wing does not ride on a cusion of air, a lift is created the pulls the top of the wing!
Let's set the record straighter.
The wing is formed in such a way that forces air to travel a further distance across the top surface of the wing than the bottom surface. Because of this, the air has to 'stretch'. This 'stretching' has the effect of lowering the density and, therefore, air pressure on the top of the wing. The larger force of the denser air on the bottom of the wing is able to overcome the smaller force of the less dense air on the top of the wing, pushing the wing up from the bottom, in that sense.
I've got Bernoulli on my speed dial.

[AZJD]

The treadmill will not counter forward movement of the plane. That is the whole point of aircraft landing gear.
Landing gear on a carrier?! :idea:
They have what is called a catapault system which works like a slingshot! This indeed creates headwind. It is moving the aircraft forward!
They use this system to create, or double the MOMENTUM needed to take off on such short runways!

[AirtimeLavey]

ROTFLMAO.....this is too good. :boxed: I wonder how many pages the circular arguing will go? :idea:
Even if the plane doesn't take off, this thread sure did. :boxed:

[clownpuncher]

It will fly. Done deal

[AZJD]

Let's set the record straighter.
The wing is formed in such a way that forces air to travel a further distance across the top surface of the wing than the bottom surface. Because of this, the air has to 'stretch'. This 'stretching' has the effect of lowering the density and, therefore, air pressure on the top of the wing. The larger force of the denser air on the bottom of the wing is able to overcome the smaller force of the less dense air on the top of the wing, pushing the wing up from the bottom, in that sense.
I've got Bernoulli on my speed dial.
:) :) :)

[Tom Brown]

Landing gear on a carrier?! :idea:
I assume you're talking about an aircraft carrier. There is no aircraft carrier on this conveyor belt.

[AZJD]

I assume you're talking about an aircraft carrier. There is no aircraft carrier on this conveyor belt.
Mixed up my response between yourself and SB's post! :cool:

[AirtimeLavey]

Let's set the record straighter.
The wing is formed in such a way that forces air to travel a further distance across the top surface of the wing than the bottom surface. Because of this, the air has to 'stretch'. This 'stretching' has the effect of lowering the density and, therefore, air pressure on the top of the wing. The larger force of the denser air on the bottom of the wing is able to overcome the smaller force of the less dense air on the top of the wing, pushing the wing up from the bottom, in that sense.
I've got Bernoulli on my speed dial.
LOL....Excuse me, this is correct.
Can they make a treadmill that can hold a multi-ton airplane and spin at over 200 knots? Now that would be impressive. Geez, think of the energy bill to power that thing? Wonder why they don't have them already? :rolleyes:

[AZJD]

I assume you're talking about an aircraft carrier. There is no aircraft carrier on this conveyor belt.
If there was, would it be able to plane out!!!!????????? And if so, how long would it take to do so!?

[Tom Brown]

Can they make a treadmill that can hold a multi-ton airplane and spin at over 200 knots?
I think this could be proven experimentally with a model aircraft and an industrial conveyor. Some of those coal conveyors can hustle along pretty well.
If the conveyor can run at a rate of 40 mph, there are lots of model aircraft that can lift off at that speed.
Simply find how much throttle is required to run the aircraft at 40 mph (in this example). Perhaps that is 1/2 throttle. Then, put the plane on the conveyor and slowly crank it up as you increase throttle on the model aircraft to a maximum of 1/2. This should provide effective results to prove/disprove this question.

[Tom Brown]

If there was...
I like your avatar.

[HEDJUG]

Because it is on a treadmill that is countering any forward movement by matching its wheelspeed, or attempt at generating groundspeed!
Wrong. Wheel speed has little or no effect. The wheels will spin faster, that’s it. But the force propelling the craft forward has nothing to do with what the ground is doing (in this case). You are thinking of it in terms of what a car would do, not a plane. A car relies on friction from the ground to push the car along, a plane doesn’t. A plane doesn't use the ground in any way to create movement, it uses air. The engines will push air, move the plane, the wheels will roll, the plane will gain speed & take off.
This is actually very simple.

[AZJD]

I think this could be proven experimentally with a model aircraft and an industrial conveyor. Some of those coal conveyors can hustle along pretty well.
If the conveyor can run at a rate of 40 mph, there are lots of model aircraft that can lift off at that speed.
Simply find how much throttle is required to run the aircraft at 40 mph (in this example). Perhaps that is 1/2 throttle. Then, put the plane on the conveyor and slowly crank it up as you increase throttle on the model aircraft to a maximum of 1/2. This should provide effective results to prove/disprove this question.
Where is the headwind coming from that is required to create lift??????????? :mad: :)

[AZJD]

Wrong. Wheel speed has little or no effect. The wheels will spin faster, that’s it. But the force propelling the craft forward has nothing to do with what the ground is doing (in this case). You are thinking of it in terms of what a car would do, not a plane. A car relies on friction from the ground to push the car along, a plane doesn’t. A plane doesn't use the ground in any way to create movement, it uses air. The engines will push air, move the plane, the wheels will roll, the plane will gain speed & take off.
This is actually very simple.
NOT IF IT CANT GENERATE FORWARD MOVEMENT!!!!!!!!!!!!!! THIS IS SIMPLE PEOPLE! If the plane cannot move forward gaining momentum it will not generate the lift................................. :mad: :mad: :mad: :mad:

[Tom Brown]

Where is the headwind coming from that is required to create lift??????????? :mad: :)
It might come from engine thrust. You never know. :)

[Tom Brown]

THIS IS SIMPLE PEOPLE!
I couldn't agree more but some people seem to be struggling with it.

[Jbb]

Brown...Im coming up there to kick your ass... :mad:

[Sleek-Jet]

I think this could be proven experimentally with a model aircraft and an industrial conveyor. Some of those coal conveyors can hustle along pretty well.
If the conveyor can run at a rate of 40 mph, there are lots of model aircraft that can lift off at that speed.
Simply find how much throttle is required to run the aircraft at 40 mph (in this example). Perhaps that is 1/2 throttle. Then, put the plane on the conveyor and slowly crank it up as you increase throttle on the model aircraft to a maximum of 1/2. This should provide effective results to prove/disprove this question.
I suggested that... I was ignored... feel free to continue to do so...
No where in the question does it state the airplane cannot move... just that it starts out stationary.
Plus it BS anyway... we don't know what the treadmill is counter acting, ground speed or air speed...
And Bernoulli was a wrong... it takes money to make an airplane fly... :idea:

[AZJD]

It might come from engine thrust. You never know. :)
Its not enough! And besides if we are talking about your typical commercial airliner, the thrust is expelled under the wing.........

[ratso]

http://www.youtube.com/watch?v=OGs_tux3quw
...okay, let's just use this for an example... :jawdrop:

[Tom Brown]

NOT IF IT CANT GENERATE FORWARD MOVEMENT!!!!!!!!!!!!!!
Those exclamation points are not adding any value to your argument.
If you had a trailer with an offset hitch so that the trailer could trail your truck in the adjacent lane, and if you put that trailer on a conveyor belt under the trailer traveling in the opposite direction of your truck at 60 mph, would you be standing still when your truck speedo was registering 60 mph?

[AZJD]

I suggested that... I was ignored... feel free to continue to do so...
No where in the question does it state the airplane cannot move... just that it starts out stationary.
Plus it BS anyway... we don't know what the treadmill is counter acting, ground speed or air speed...
And Bernoulli was a wrong... it takes money to make an airplane fly... :idea:
The question states that what ever speen is attained it will be countered by the treadmill! In this case AIRSPEED and GROUNDSPEED will be ZERO............The plane cannot move! GAWSH!

[racecar.hotshoe]

http://www.youtube.com/watch?v=OGs_tux3quw
...okay, let's just use this for an example... :jawdrop:
I dont know much but I do know she wont fly.........Thanks I was having lunch.... :rolleyes:

[ratso]

Those exclamation points are not adding any value to your argument.
If you had a trailer with an offset hitch so that the trailer could trail your truck in the adjacent lane, and if you put that trailer on a conveyor belt under the trailer traveling in the opposite direction of your truck at 60 mph, would you be standing still when your truck speedo was registering 60 mph?
...no. :idea:

[Tom Brown]

The question states that what ever speen is attained it will be countered by the treadmill!
No it doesn't!! :D
Give this a read:
A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?

[AZJD]

Those exclamation points are not adding any value to your argument.
If you had a trailer with an offset hitch so that the trailer could trail your truck in the adjacent lane, and if you put that trailer on a conveyor belt under the trailer traveling in the opposite direction of your truck at 60 mph, would you be standing still when your truck speedo was registering 60 mph?
Now your just stirring the pot! :) :) :)

[Sleek-Jet]

The question states that what ever speen is attained it will be countered by the treadmill! In this case AIRSPEED and GROUNDSPEED will be ZERO............The plane cannot move! GAWSH!
They are measured differently... so which is it, airspeed or groundspeed...

[Tom Brown]

I dont know much but I do know she wont fly.........Thanks I was having lunch.... :rolleyes:
According to HavasuBarney, you could put a jet engine up her ass and achieve flight.

[ratso]

I dont know much but I do know she wont fly.........Thanks I was having lunch.... :rolleyes:
http://www.youtube.com/watch?v=-UAfP0b3vno
...they do for a lil bit.

[Hal]

As said many times the plane uses thrust to move forward to get to takeoff speed and is not driven by wheel power. The thrust that moves the plane forward couldn't care less what the wheels on the conveyor belt are doing as long as they are freewheeling.
For every pound of thrust produced by the jet engines there is an equal amount of thrust applied in the opposite direction.
The only way you could stop the plane from moving forward and taking off would be to install the equal amount of engines with equal amount of thrust facing the opposite direction on the plane.
The only effect the conveyor belt could have on the plane is that it would cause the wheels to turn twice as fast as they normally would.
The conveyor belt could match the plane speed in the opposite direction but its not going to have anything to do the forward movement of the plane.
The plane would thrust itself forward up to take off speed and take off no matter how fast the belt goes.
I guess if the plane needs to reach 150 mph to take off the belt would match that speed in the opposite direction at 150 mph but there will be a 300 mph difference in the plane speed and the belt speed.
Hum, I wonder what would happen if we replaced the conveyor belt with a wind tunnel?

[Tom Brown]

Now your just stirring the pot! :) :) :)
No I'm not. Aircraft landing gear free wheels when the brakes are not applied. You could hook an airplane to the back of your truck and tow it like a trailer. Because of that, aircraft wheel speed is pretty much irrelevant.

[AirtimeLavey]

Ok, my cheeks hurt from laughing. :crossx:
What if the runway is slanted downhill? Is the plane going slide down the runway conveyor, or stay stationary? :idea: :boxed:

[HEDJUG]

NOT IF IT CANT GENERATE FORWARD MOVEMENT!!!!!!!!!!!!!! THIS IS SIMPLE PEOPLE! If the plane cannot move forward gaining momentum it will not generate the lift................................. :mad: :mad: :mad: :mad:
IT CAN MOVE FOWARD. ITS CALLED THRUST. THRUST PUSHES THE PLANE REGARDLESS OF WHAT THE GROUND IS DOING. TAKE THE FRIGGIN WHEELS OFF & THE PLANE WILL STILL GO(till it breaks up, but it will go).
Go home & put a toy car on a moving treadmill. Hold it in one place for a while. Then gently push the car forward with your arm. The car will easily go forward. Your arm is pushing the car just as the jet engine will push the plane. The plane will go foward & create lift. Thats it. Simple.
You are slowly killing me.

[Sleek-Jet]

Hum, I wonder what would happen if we replaced the conveyor belt with a wind tunnel?
Hal, that would change everything in relation to the question that was asked as wind does directly effect the lift of the plane. Ask any pilot and they'll tell you that head wind or tailwind will increase or decrease the speed of rotation or landing by just that amount. Also increases or decreases the amount of runway consumned(sp).
Rio
No it doesn't Rio... an airplane lands and takes-off at the same airspeed, no matter what the wind is doing.
Now, if we are talking ground speed, than yes, that is different based on a headwind or tailwind or crosswind. And it does increase or decrease the amount of runway used.
But the airspeed remains the same.

[Tom Brown]

Now, if we are talking ground speed, than yes, that is different based on a headwind or tailwind or crosswind.
Interesting. He said 'speed of rotation' which I would take to mean airspeed, just as you have assumed.

[AirtimeLavey]

Airtimelavey, Riverside airport is a prime example of a runway that slants downhill. Go put an plane on the ne end and see if it'll roll downhill.
Rio
Yeah, but it needs to have a conveyor as well for my question. :)

[Tom Brown]

If you're the top man in an airtight chick project, will your forward thrust be counter acted by the woman's tongue sliding out toward your balls as you push your man hood deeper into her oral cavity? :idea:

[AZJD]

Alright, I think I get it! If I load my truck and boat on a treadmill and set it to run 80mph would I still reach Havasu in 3 1/2 hrs. And would I bur 3/4 of a tank of diesel too?

[Tom Brown]

Alright, I think I get it!
That makes one of us.

[Tom Brown]

If I load my truck and boat on a treadmill and set it to run 80mph would I still reach Havasu in 3 1/2 hrs.
OK... how about this. (I'm just loitering until someone answers or even notices my airtight question)
If you put your truck on a conveyor that travels in the opposite direction of your truck at 80 mph, and you run your truck in forward gear so it indicates 80 mph, a few people here would probably agree that the truck will be geographically stationary.
OK.... now if you slipped your truck into neutral and fired up a jet engine on a nacell that is mounted to the bed of your pickup (intake above the cab), would that jet be disadvantaged the same 80 mph that your diesel engine running the drive wheels was?

[Schiada76]

If you dropped a car revved to the max in gear from say under the wing of a B-52 at 30000 ft it'll make a nice dent in the earth.
Drop a jet powered aircraft from the same plane and it will fly.
Does that help? :rolleyes:

[AZJD]

That makes one of us.
I'm still right i just dont wanna argue anymore........It makes me want to drink! :argue: :)

[CBadDad]

I've changed my mind so many times on this subject, I'm not sure what I believe right now.
Thanks

[Tom Brown]

I'm still right i just dont wanna argue anymore........
Now we're getting somewhere. :cool:

[lucky]

Now we're getting somewhere. :cool:
talk about ****ing up hot boat !

[AZJD]

Now we're getting somewhere. :cool:
But I do wanna drink!

[Sleek-Jet]

I've changed my mind so many times on this subject, I'm not sure what I believe right now.
Thanks
God is a gigantic Spaghetti monster... :idea:

[Tom Brown]

Here's a question:
If you routinely discover a gerbil carcass in the toilet bowl after a bowl movement, does that automatically mean you're gay?

[AZJD]

Here's a question:
If you routinely discover a gerbil carcass in the toilet bowl after a bowl movement, does that automatically mean you're gay?
Only if someone else sees it too! Kinda like when the tree falls in the middle of the forrest, does it make a sound! Only if someone is there to see it!

[lucky]

Here's a question:
If you routinely discover a gerbil carcass in the toilet bowl after a bowl movement, does that automatically mean you're gay?
that or your boyfriend purgded first

[AirtimeLavey]

is the gerbil male or female...?

[AZJD]

Here's a question:
If you routinely discover a gerbil carcass in the toilet bowl after a bowl movement, does that automatically mean you're gay?
Maybe it died on the treadmill! :crossx: It must be harder to run on then the wheel.

[lucky]

if the plane took off , the treadmill stopped , and the gerbil flew - what would the odds be that it would die up your ass ?

[ZBODaytona]

wow this went to 9 pages...guess i will have to put it on another forum see how long it goes...hmm must be the weather for some people

[Tom Brown]

wow this went to 9 pages...guess i will have to put it on another forum see how long it goes...hmm must be the weather for some people
While you're here, can you tell me which is more important, torque or horsepower?

[AZJD]

While you're here, can you tell me which is more important, torque or horsepower?
Depends on the application!

[ZBODaytona]

i like both.......more the better

[AZJD]

i like both.......more the better
Yes but if you have a light weight sports car torque is not your friend!

[AZJD]

Bob Marley said it best: Stir it up!

[HM]

OK... how about this. (I'm just loitering until someone answers or even notices my airtight question)
If you put your truck on a conveyor that travels in the opposite direction of your truck at 80 mph, and you run your truck in forward gear so it indicates 80 mph, a few people here would probably agree that the truck will be geographically stationary.
The speedo would be reading a speed relative to the conveyor belt. If you had a GPS speedo in the truck, and the conveyor belt was going 80, you would only be moving forward at 10 MPH in a Ford and you would be doing 80 MPH in a Chevy. :crossx:

[AZJD]

The speedo would be reading a speed relative to the conveyor belt. If you had a GPS speedo in the truck, and the conveyor belt was going 80, you would only be moving forward at 10 MPH in a Ford and you would be doing 80 MPH in a Chevy. :crossx:
Yes but would you burn the same amount of fuel as traveling on pavement?

[Tom Brown]

HolyMoly, canuck1 asked me to give you a message.
... but before I do, is he mad at you or something? :confused:

[HM]

Yes but would you burn the same amount of fuel as traveling on pavement?
Depends on if you have a turbonator. :D

[HM]

HolyMoly, canuck1 asked me to give you a message.
... but before I do, is he mad at you or something? :confused:
Yah, I pulled out and shot it in his eye. :crossx:

[Tom Brown]

What did Hoolign say when you did that? :D

[AZJD]

Depends on if you have a turbonator. :D
I use the fastfreddy blower switch for my turbo...........but only when I need the extra power for passing!

[Debbolas]

It depends on what the people in the plane are wearing :D
Someone (a very cute guy) once described flying to me in this way....a plane is pretty much just an "add on" to the wing, the wing is responsible for the lift. Wings fly and you just add the fuseloge (sp) to them to carry people.
Now, I am blonde, but it seems to me that if there is no lift/air under the wing, it doesn't matter how fast the wheels on the treadmill turn, the plane will not fly :D

[HM]

What did Hoolign say when you did that? :D
No Fair!!!

[HM]

It depends on what the people in the plane are wearing :D
Someone (a very cute guy) once described flying to me in this way....a plane is pretty much just an "add on" to the wing, the wing is responsible for the lift. Wings fly and you just add the fuseloge (sp) to them to carry people.
Now, I am blonde, but it seems to me that if there is no lift/air under the wing, it doesn't matter how fast the wheels on the treadmill turn, the plane will not fly :D
Math is hard. You sat next to Jordy?

[Desert Rat]

LOL....Excuse me, this is correct.
Can they make a treadmill that can hold a multi-ton airplane and spin at over 200 knots? Now that would be impressive. Geez, think of the energy bill to power that thing? Wonder why they don't have them already? :rolleyes:
Nuclear power available on carriers can produce more then enough power for such a contraption. I think the US Navy would have more then enough $$ to complete such a project that is if it would work (which it won't) :rolleyes:

[Tom Brown]

... so if there is no water under a boat to float it, will it sink?

[lucky]

i wonder if the same theroy applys to tampoons with wings ? I'm gonna have to go fly some of dem

[AZJD]

... so if there is no water under a boat to float it, will it sink?
If there is no water it wouldn't be considered sinking......... :)

[HM]

If Her454 weighs as much as a duck, she's a witch!

[Debbolas]

Math is hard. You sat next to Jordy?
No! :rolleyes: He's an ass ;)
was I wrong? I have to go teach some more kids and don't want to scroll back through.......

[Debbolas]

... so if there is no water under a boat to float it, will it sink?
If it isn't on a trailer it will tilt to one side :D

[Debbolas]

If Her454 weighs as much as a duck, she's a witch!
I LOVE that Monty Python movie :D

[AirtimeLavey]

No! :rolleyes: He's an ass ;)
was I wrong? I have to go teach some more kids and don't want to scroll back through.......
:2purples:
j/k, just don't give them flying lessons. ;) :D

[Tom Brown]

was I wrong?
Not if you don't admit it.

[RiverDave]

I read to page 6 before I couldn't take it anymore..
You guys are literally answering
What does a cow drink?
"Milk" everytime, and even after thinking about it, still saying milk.. (the right answer is water)
A plane is "standing" on a conveyor belt. I.E. the plane is free standing engines off.
Plane speed is 0, conveyor speed is zero..
Now common sense would say that if the plane moved 2mph forward and the conveyor moved 2mph backwards the plane would stand still. That however is INCORRECT, becuase the plane as mentioned before is not dependant upon ground speed. The wheels would now be doing 4 mph (matches the plane speed, but opposite direction), but the plane will still be doing 2mph forward.. Thus when the plane reaches take off speed, the wheels will be travelling twice as fast as they normally do, but the plane still takes off..
Now the thing that seems to be throwing everyone for a loop is ground speed vs air speed. They are not a 1:1 equation, becuase they are totally independant of each other. It doesn't matter if the ground speed is a million mph, and the plane speed is 1mph, the plane will still be travelling forward at 1mph and the tires will be travelling at 1,000,001 mph.
This of course is disregarding the drag coefficients of the tires, but in reality good luck building a million mph conveyor belt too so the point is mute.
The plane will take off regardless in any of those situations.
If you work the question backwards it becomes very apparent in a hurry.
If a plane is tied to a wall in front of it, via the wing tips, and a conveyor was underneath the tires.. Does it matter how fast that conveyor ever spins? The plane will never move, windspeed will be zero regardless of ground speed. They are in fact independant of each other in every circumstance regardless of how exponential one might be to the other.
Sorry Jordy your logic is f'd on this one. ;) :D
RD

[Tom Brown]

Dave, you are wrong and I am right but I don't feel like discussing it anymore.

[Debbolas]

:2purples:
j/k, just don't give them flying lessons. ;) :D
I teach reading :rolleyes: ;)
I don't need to fly a plane :D

[Halvecta]

A plane is standing on a runway that can move (like a giant conveyor
belt). This conveyor has a control system that tracks the plane's
speed and tunes the speed of the conveyor to be exactly the same (but
in the opposite direction) instantly.
Will the plane be able to take off?[/QUOTE]
Yep.
The whole argument for not moving is already answered by the question. The only way the conveyor belt moves at all is if the "planes speed" (which tells me THE PLANE IS moving) is greater than zero. If the plane was "standing still" then the conveyor belt would be too.
The Fasten Seat Belt Light is Now On, please place your seat in its upright position and stow and secure any tray tables at this time. We are about begin our flight"
Take 2 and check the thread in the morning.

[BajaMike]

Nuclear power available on carriers can produce more then enough power for such a contraption. I think the US Navy would have more then enough $$ to complete such a project that is if it would work (which it won't) :rolleyes:
Good point, they could make the carriers a lot smaller and do away with those catapult things!!!
:idea:

[Tom Brown]

The whole argument for not moving is already answered by the question.
Not necessarily. It could easily be interpreted as the 'standing' position being the initial state of the experiment, prior to the plane trying to take off. This is how others and myself have interpreted the question.
It's also how the question was intended. If you read back a few pages, you will see the person who posed the question has said your position of the plane not moving is incorrect.

[SHOTKALLIN]

this thread is retarded. i cant believe it has gone 10 pages. post whores :rolleyes:

[RiverDave]

Point being Tom you can't hold the plane still regardless of ground speed. So it's irrelevant if the plane was static or moving?
If the plane is zero, and the conveyor belt "lurched" 100 mph for 2 seconds.. Disregarding drag coefficients again, the plane would still be in the same place.
This is almost like asking, if you lower the landing gear and the wheels are stopped, does the plane fall out of the sky? :D :D
RD

[Tom Brown]

this thread is retarded.
... as are all who post in it. :)

[Halvecta]

If the planes GPS reads 80, what does the treadmill's speedo read? HMMM, that would mean the plane is moving forward, eh? (for you Canucks).
In the scenario that the plane cannot take off, the plane GPS would be reading 0, then how is the treadmill not also at 0, remember it is automatically adjusting to the planes speed (i.e. GPS reading)?
Three speeds:
Plane speed - X
Treadmill speed - X
wheel speed - 2x
Chicken or the Egg? Beef or Chicken? Taco Bell or Del Taco?

[AirtimeLavey]

This is almost like asking, if you lower the landing gear and the wheels are stopped, does the plane fall out of the sky? :D :D
RD
Lol....great answer. This should clear things up. :cool:

[Tom Brown]

If the plane is zero, and the conveyor belt "lurched" 100 mph for 2 seconds.. Disregarding drag coefficients again, the plane would still be in the same place.
Interesting. I was going to use the analogy of pulling the table cloth out from under the dishes.
This is almost like asking, if you lower the landing gear and the wheels are stopped, does the plane fall out of the sky? :D :D
It seems clear lots of people think it would.
A while ago, I asked which boat would win a drag race between an 8 second boat and a 10 second boat. Most of the answers were, "it depends". They wanted to talk about torque (since it's more important than horsepower :D), induction systems, etc. Nobody questioned the reaction time aspect or anything relevant.
We need more Asian immigrants to bring up our science marks.

[RiverDave]

If the planes GPS reads 80, what does the treadmill's speedo read?
In the scenario that the plane cannot take off, the plane GPS would be reading 0, then how is the treadmill not also?
Chicken or the Egg? Beef or Chicken? Taco Bell or Del Taco?
If the planes GPS reads 80, then the MPH on the conveyor belt would be 80mph in the opposite direction.. (As answered by the original question "MATCHING PLANE SPEED IN THE OPPOSITE DIRECTION." The tires would now be doing 160mph though, and the plane will still be moving 80mph in a forward direction.
Again though The plane could read 80mph, and the conveyor could be 200mph, it doesn't matter.. The tires will be doing 280mph and the plane will still be doing 80mph and on it's way to take off.
RD

[Jbb]

If you're the top man in an airtight chick project
:p :p :p