Can the plane take off?

No matter how fast the conveyor turns the wheels are just going to turn twice as fast as the plane is moving but the plane is going to move forward immediately regardless of the conveyor.
If the conveyor is as long as a runway the plane will take off while on the conveyor. If not the plane will run off the end of it.
Either way the plane is going to take off as it normally does.
Edit: The engine thrust will cause it to move forward against the wind and if there is no wind then away from its position on earth as soon as the engines start to produce thrust and the brakes are released.
 
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ttmott said:
The airplane has it's own power right? Consequently, it can take off.
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Let’s bring this into context. The riddle is deceptively worded. If it said the conveyor belt matches the speed with an opposite vector of the aircraft speed (aka physicists definition of velocity) everybody would get it instantly; you don’t go anywhere when your boat only does 5 knots and you are running into an oncoming 5 knot current.
 
The better question would be.
If the plane were sitting perfectly still in a perfect straight on 200 mph head wind would it take off while sitting perfectly still.
Yep, it would.
 
There's a video somewhere, I'll see if I can find it ...

A woman is at the airport, using the moving walkway but walking against the direction of the belt so she's not really getting anywhere. Then she sees people on the other side flying by and realizing what's going on :D
 
Henry Boyd said:
Let’s bring this into context. The riddle is deceptively worded. If it said the conveyor belt matches the speed with an opposite vector of the aircraft speed (aka physicists definition of velocity) everybody would get it instantly; you don’t go anywhere when your boat only does 5 knots and you are running into an oncoming 5 knot current.
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Matched the speed of the wheels. If the thrust of the engines is moving the aircraft down the conveyor (which is the length of a runway) who cares what the wheels are doing? Unlike a boat the thrust isn't using the conveyor (water).
Now if the thrust is normally rotating the wheels by moving down the runway then therefore as the conveyor is countering the wheel movement the wheels are not rotating even though the aircraft is moving down the runway (conveyor). Now, read another way the conveyor is operating opposite the aircraft moving down the runway then the wheels will spin double normal.
spinning the wheels has nothing to do with the aircraft moving under it's own power.
 
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Henry Boyd said:
Let’s bring this into context. The riddle is deceptively worded. If it said the conveyor belt matches the speed with an opposite vector of the aircraft speed (aka physicists definition of velocity) everybody would get it instantly; you don’t go anywhere when your boat only does 5 knots and you are running into an oncoming 5 knot current.
Click to expand...

It's not deceptive. The conveyor only matches the speed of the wheels, not the plane. For an airplane the speed of the wheels during takeoff is not relevant.

Will this same 747 sitting on a runway, not moving relative to the runway, be able to take off in a 180mph headwind (with wheels that are not moving)? Yes, yes it sure will. Just like the one on the conveyor belt :)
 
tc410 said:
You need air flow over the wings. When you’re running on a treadmill, how much wind do you feel in your face? None.
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Oh now..... Nothing is driving against the "treadmill" like running. The energy and force to move the aircraft forward and get that airflow over the wings has nothing to do with the conveyor. It's the engines forcing air and gasses out the exhaust.
 
Henry Boyd said:
Let’s bring this into context. The riddle is deceptively worded. If it said the conveyor belt matches the speed with an opposite vector of the aircraft speed (aka physicists definition of velocity) everybody would get it instantly; you don’t go anywhere when your boat only does 5 knots and you are running into an oncoming 5 knot current.
Click to expand...

What's our Vector, Victor?

 
ttmott said:
Oh now..... Nothing is driving against the "treadmill" like running. The energy and force to move the aircraft forward and get that airflow over the wings has nothing to do with the conveyor. It's the engines forcing air and gasses out the exhaust.
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Correct. The plane uses the engines thrust which require air to move forward, not the wheels on the treadmill.
 
OllieC said:
Correct. The plane uses the engines thrust which require air to move forward, not the wheels.
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And if the conveyor is counter-spinning the wheels at the same speed as the wheels then the wheels are not turning at all and the aircraft still takes flight.
 
Easy answer, no it's can't, "exactly" is the key word here. The airplane has to move forward relative to the ground. So long as the conveyor belt is matching the speed "exactly", it cannot move forward.
 
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tc410 said:
You need air flow over the wings. When you’re running on a treadmill, how much wind do you feel in your face? None.
Click to expand...

You actually need wind under your wings to create lift.

The plane will take off in this story problem. The thrust pushes the plane forward. Doesn't matter how fast or slow the treadmill is running. It is irrelevant.
 
mrsrobinson said:
Easy answer, no it's can't, it's propositional logic..."exactly" is the key word here. The airplane has to move forward relative to the ground. So long as the conveyor belt is matching the speed exactly, it cannot move forward.
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Sooo...you're saying that a 747 with 0mph speed over ground will NOT take off with a 180mph headwind?

Is the stall speed of an airplane (or wing) defined in terms of ground speed?

Was it a ground speed indicator that got Boeing into all that trouble a couple years back? :):)
 
Stee6043 said:
Sooo...you're saying that a 747 with 0mph speed over ground will NOT take off with a 180mph headwind?

Is the stall speed of an airplane (or wing) defined in terms of ground speed?

Was it a ground speed indicator that got Boeing into all that trouble a couple years back? :):)
Click to expand...
There’s no mention of headwind in the OPs proposition. Where are you getting this headwind theory from?
 
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