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Trailer Park Casanova
11-07-2007, 06:26 PM
Read it and weep:
As the wing passes through the air, a low pressure area is created on top of the wing and a high pressure area is created under the wing. The combination of the low and high pressure areas lift the wing, which lifts the aircraft.
If the plane is on a tredmill, no air will pass over the wing to lift it, It will remain stationary.
http://www.grc.nasa.gov/WWW/K-12/airplane/Images/forces.gif
A force may be thought of as a push or pull in a specific direction. A force is a vector quantity so a force has both a magnitude and a direction. When describing forces, we have to specify both the magnitude and the direction. This slide shows the forces that act on an airplane in flight.
Weight
Weight is a force that is always directed toward the center of the earth. The magnitude of the weight depends on the mass of all the airplane parts, plus the amount of fuel, plus any payload on board (people, baggage, freight, etc.). The weight is distributed throughout the airplane. But we can often think of it as collected and acting through a single point called the center of gravity. In flight, the airplane rotates about the center of gravity.
Flying encompasses two major problems; overcoming the weight of an object by some opposing force, and controlling the object in flight. Both of these problems are related to the object's weight and the location of the center of gravity. During a flight, an airplane's weight constantly changes as the aircraft consumes fuel. The distribution of the weight and the center of gravity also changes. So the pilot must constantly adjust the controls to keep the airplane balanced, or trimmed.
Lift
To overcome the weight force, airplanes generate an opposing force called lift. Lift is generated by the motion of the airplane through the air and is an aerodynamic force. "Aero" stands for the air, and "dynamic" denotes motion. Lift is directed perpendicular to the flight direction. The magnitude of the lift depends on several factors including the shape, size, and velocity of the aircraft. As with weight, each part of the aircraft contributes to the aircraft lift force. Most of the lift is generated by the wings. Aircraft lift acts through a single point called the center of pressure. The center of pressure is defined just like the center of gravity, but using the pressure distribution around the body instead of the weight distribution.
The distribution of lift around the aircraft is important for solving the control problem. Aerodynamic surfaces are used to control the aircraft in roll, pitch, and yaw.
Drag
As the airplane moves through the air, there is another aerodynamic force present. The air resists the motion of the aircraft and the resistance force is called drag. Drag is directed along and opposed to the flight direction. Like lift, there are many factors that affect the magnitude of the drag force including the shape of the aircraft, the "stickiness" of the air, and the velocity of the aircraft. Like lift, we collect all of the individual components' drags and combine them into a single aircraft drag magnitude. And like lift, drag acts through the aircraft center of pressure.
Thrust
To overcome drag, airplanes use a propulsion system to generate a force called thrust. The direction of the thrust force depends on how the engines are attached to the aircraft. In the figure shown above, two turbine engines are located under the wings, parallel to the body, with thrust acting along the body centerline. On some aircraft, such as the Harrier, the thrust direction can be varied to help the airplane take off in a very short distance. The magnitude of the thrust depends on many factors associated with the propulsion system including the type of engine, the number of engines, and the throttle setting.
For jet engines, it is often confusing to remember that aircraft thrust is a reaction to the hot gas rushing out of the nozzle. The hot gas goes out the back, but the thrust pushes towards the front. Action <--> reaction is explained by Newton's Third Law of Motion.
The motion of the airplane through the air depends on the relative strength and direction of the forces shown above. If the forces are balanced, the aircraft cruises at constant velocity. If the forces are unbalanced, the aircraft accelerates in the direction of the largest force.
Note that the job of the engine is just to overcome the drag of the airplane, not to lift the airplane. A 1 million pound airliner has 4 engines that produce a grand total of 200,000 of thrust. The wings are doing the lifting, not the engines. In fact, there are some aircraft, called gliders that have no engines at all, but fly just fine. Some external source of power has to be applied to initiate the motion necessary for the wings to produce lift. But during flight, the weight is opposed by both lift and drag. Paper airplanes are the most obvious example, but there are many kinds of gliders. Some gliders are piloted and are towed aloft by a powered aircraft, then cut free to glide for long distances before landing. During reentry and landing, the Space Shuttle is a glider; the rocket engines are used only to loft the Shuttle into space.
You can view a short movie of "Orville and Wilbur Wright" explaining how the four forces of weight, lift, drag and thrust affected the flight of their aircraft. The movie file can be saved to your computer and viewed as a Podcast on your podcast player.

centerhill condor
11-07-2007, 06:46 PM
this is gettin' out of hand...
CC

Nord
11-07-2007, 06:48 PM
You know what this reminds me of.............The old cartoons when the character is in the elevator that is falling. As soon as the elevator gets to the bottom, the character walks off unharmed and the elevator is crushed on impact......lol

Tom Brown
11-07-2007, 06:49 PM
I don't believe in aerodynamics.

CornWater
11-07-2007, 06:51 PM
I don't believe in aerodynamics.
I suppose you believe airplanes where just "created"...

Tom Brown
11-07-2007, 06:52 PM
I suppose you believe airplanes where just "created"...
Yes I do. There is no way they could have evolved so that argument is not credible.

CornWater
11-07-2007, 06:54 PM
Yes I do. There is no way they could have evolved so that argument is not credible.
:D

Excessive Force
11-07-2007, 07:03 PM
all them arrows made me think it was a sex manual...thrust...lift....

Trailer Park Casanova
11-07-2007, 07:08 PM
I don't believe in aerodynamics.
I know dotcommunism when I read it. That's it, Roland and I are bustin' out the fraternity hazing paddles and heading north,,

EAZYKILLER2006
11-07-2007, 07:13 PM
by the look of the size of that the head, does not look like it will get up and thrust:mad:
tommy i am with you
it aint getting up, but for the sake of argument... if it does get up:D it aint staying up...
so whats the point?

Wet Dream
11-07-2007, 07:14 PM
Ahhhhhhh, horseshit!!! With the wing design, low pressure creating lift, explain how the same plane can fly upside down without crashing to earth. This was proven so long ago. I'll give you the answer shortly. :rolleyes:

OverKill
11-07-2007, 07:21 PM
[QUOTE=Trailer Park Casanova;2881751]Read it and weep:
As the wing passes through the air, a low pressure area is created on top of the wing and a high pressure area is created under the wing. The combination of the low and high pressure areas lift the wing, which lifts the aircraft.
If the plane is on a tredmill, no air will pass over the wing to lift it, It will remain stationary.
http://www.grc.nasa.gov/WWW/K-12/airplane/Images/forces.gif
A force may be thought of as a push or pull in a specific direction. A force is a vector quantity so a force has both a magnitude and a direction. When describing forces, we have to specify both the magnitude and the direction. This slide shows the forces that act on an airplane in flight.
Weight
Weight is a force that is always directed toward the center of the earth. The magnitude of the weight depends on the mass of all the airplane parts, plus the amount of fuel, plus any payload on board (people, baggage, freight, etc.). The weight is distributed throughout the airplane. But we can often think of it as collected and acting through a single point called the center of gravity. In flight, the airplane rotates about the center of gravity.
Flying encompasses two major problems; overcoming the weight of an object by some opposing force, and controlling the object in flight. Both of these problems are related to the object's weight and the location of the center of gravity. During a flight, an airplane's weight constantly changes as the aircraft consumes fuel. The distribution of the weight and the center of gravity also changes. So the pilot must constantly adjust the controls to keep the airplane balanced, or trimmed.
Lift
To overcome the weight force, airplanes generate an opposing force called lift. Lift is generated by the motion of the airplane through the air and is an aerodynamic force. "Aero" stands for the air, and "dynamic" denotes motion. Lift is directed perpendicular to the flight direction. The magnitude of the lift depends on several factors including the shape, size, and velocity of the aircraft. As with weight, each part of the aircraft contributes to the aircraft lift force. Most of the lift is generated by the wings. Aircraft lift acts through a single point called the center of pressure. The center of pressure is defined just like the center of gravity, but using the pressure distribution around the body instead of the weight distribution.
The distribution of lift around the aircraft is important for solving the control problem. Aerodynamic surfaces are used to control the aircraft in roll, pitch, and yaw.
Drag
As the airplane moves through the air, there is another aerodynamic force present. The air resists the motion of the aircraft and the resistance force is called drag. Drag is directed along and opposed to the flight direction. Like lift, there are many factors that affect the magnitude of the drag force including the shape of the aircraft, the "stickiness" of the air, and the velocity of the aircraft. Like lift, we collect all of the individual components' drags and combine them into a single aircraft drag magnitude. And like lift, drag acts through the aircraft center of pressure.
Thrust
To overcome drag, airplanes use a propulsion system to generate a force called thrust. The direction of the thrust force depends on how the engines are attached to the aircraft. In the figure shown above, two turbine engines are located under the wings, parallel to the body, with thrust acting along the body centerline. On some aircraft, such as the Harrier, the thrust direction can be varied to help the airplane take off in a very short distance. The magnitude of the thrust depends on many factors associated with the propulsion system including the type of engine, the number of engines, and the throttle setting.
For jet engines, it is often confusing to remember that aircraft thrust is a reaction to the hot gas rushing out of the nozzle. The hot gas goes out the back, but the thrust pushes towards the front. Action <--> reaction is explained by Newton's Third Law of Motion.
The motion of the airplane through the air depends on the relative strength and direction of the forces shown above. If the forces are balanced, the aircraft cruises at constant velocity. If the forces are unbalanced, the aircraft accelerates in the direction of the largest force.
Note that the job of the engine is just to overcome the drag of the airplane, not to lift the airplane. A 1 million pound airliner has 4 engines that produce a grand total of 200,000 of thrust. The wings are doing the lifting, not the engines. In fact, there are some aircraft, called gliders that have no engines at all, but fly just fine. Some external source of power has to be applied to initiate the motion necessary for the wings to produce lift. But during flight, the weight is opposed by both lift and drag. Paper airplanes are the most obvious example, but there are many kinds of gliders. Some gliders are piloted and are towed aloft by a powered aircraft, then cut free to glide for long distances before landing. During reentry and landing, the Space Shuttle is a glider; the rocket engines are used only to loft the Shuttle into space.
You can view a short movie of "Orville and Wilbur Wright" explaining how the four forces of weight, lift, drag and thrust affected the flight of their aircraft. The movie file can be saved to your computer and viewed as a Podcast on your podcast player.[/QUOT
Thank Christ someone has figured it out. I learned this S**T in High School. There shouldn't be any debate if the thing will fly on a treadmil.

LaveyJet
11-07-2007, 07:28 PM
Read it and weep:
As the wing passes through the air, a low pressure area is created on top of the wing and a high pressure area is created under the wing. The combination of the low and high pressure areas lift the wing, which lifts the aircraft.
If the plane is on a tredmill, no air will pass over the wing to lift it, It will remain stationary.
http://www.grc.nasa.gov/WWW/K-12/airplane/Images/forces.gif
A force may be thought of as a push or pull in a specific direction. A force is a vector quantity so a force has both a magnitude and a direction. When describing forces, we have to specify both the magnitude and the direction. This slide shows the forces that act on an airplane in flight.
Weight
Weight is a force that is always directed toward the center of the earth. The magnitude of the weight depends on the mass of all the airplane parts, plus the amount of fuel, plus any payload on board (people, baggage, freight, etc.). The weight is distributed throughout the airplane. But we can often think of it as collected and acting through a single point called the center of gravity. In flight, the airplane rotates about the center of gravity.
Flying encompasses two major problems; overcoming the weight of an object by some opposing force, and controlling the object in flight. Both of these problems are related to the object's weight and the location of the center of gravity. During a flight, an airplane's weight constantly changes as the aircraft consumes fuel. The distribution of the weight and the center of gravity also changes. So the pilot must constantly adjust the controls to keep the airplane balanced, or trimmed.
Lift
To overcome the weight force, airplanes generate an opposing force called lift. Lift is generated by the motion of the airplane through the air and is an aerodynamic force. "Aero" stands for the air, and "dynamic" denotes motion. Lift is directed perpendicular to the flight direction. The magnitude of the lift depends on several factors including the shape, size, and velocity of the aircraft. As with weight, each part of the aircraft contributes to the aircraft lift force. Most of the lift is generated by the wings. Aircraft lift acts through a single point called the center of pressure. The center of pressure is defined just like the center of gravity, but using the pressure distribution around the body instead of the weight distribution.
The distribution of lift around the aircraft is important for solving the control problem. Aerodynamic surfaces are used to control the aircraft in roll, pitch, and yaw.
Drag
As the airplane moves through the air, there is another aerodynamic force present. The air resists the motion of the aircraft and the resistance force is called drag. Drag is directed along and opposed to the flight direction. Like lift, there are many factors that affect the magnitude of the drag force including the shape of the aircraft, the "stickiness" of the air, and the velocity of the aircraft. Like lift, we collect all of the individual components' drags and combine them into a single aircraft drag magnitude. And like lift, drag acts through the aircraft center of pressure.
Thrust
To overcome drag, airplanes use a propulsion system to generate a force called thrust. The direction of the thrust force depends on how the engines are attached to the aircraft. In the figure shown above, two turbine engines are located under the wings, parallel to the body, with thrust acting along the body centerline. On some aircraft, such as the Harrier, the thrust direction can be varied to help the airplane take off in a very short distance. The magnitude of the thrust depends on many factors associated with the propulsion system including the type of engine, the number of engines, and the throttle setting.
For jet engines, it is often confusing to remember that aircraft thrust is a reaction to the hot gas rushing out of the nozzle. The hot gas goes out the back, but the thrust pushes towards the front. Action <--> reaction is explained by Newton's Third Law of Motion.
The motion of the airplane through the air depends on the relative strength and direction of the forces shown above. If the forces are balanced, the aircraft cruises at constant velocity. If the forces are unbalanced, the aircraft accelerates in the direction of the largest force.
Note that the job of the engine is just to overcome the drag of the airplane, not to lift the airplane. A 1 million pound airliner has 4 engines that produce a grand total of 200,000 of thrust. The wings are doing the lifting, not the engines. In fact, there are some aircraft, called gliders that have no engines at all, but fly just fine. Some external source of power has to be applied to initiate the motion necessary for the wings to produce lift. But during flight, the weight is opposed by both lift and drag. Paper airplanes are the most obvious example, but there are many kinds of gliders. Some gliders are piloted and are towed aloft by a powered aircraft, then cut free to glide for long distances before landing. During reentry and landing, the Space Shuttle is a glider; the rocket engines are used only to loft the Shuttle into space.
You can view a short movie of "Orville and Wilbur Wright" explaining how the four forces of weight, lift, drag and thrust affected the flight of their aircraft. The movie file can be saved to your computer and viewed as a Podcast on your podcast player.
Why do you think the drag from the treadmill is the same as the thrust?
The only drag from the treadmill will be the fricrion in the wheels. The thrust from the engines will be much greater than any friction force.
Remember, the engines are not pushing against the treadmill, they are pushing against the air.

Sleeper CP
11-07-2007, 07:37 PM
I don't believe in aerodynamics.
I thought is was God that you didn't beleive in:confused:
Sleeper CP

Nord
11-07-2007, 07:46 PM
I thought is was God that you didn't beleive in:confused:
Sleeper CP
God created aerodynamics ;) :D

DeltaSigBoater
11-07-2007, 08:21 PM
I think we all needs to take a field trip to a high school physics class

maxwedge
11-07-2007, 08:25 PM
I think a trip to the airport or the gym would be more productive at this point.

Wet Dream
11-08-2007, 10:39 AM
Its called ANGLE OF ATTACK.
Here are some things to help you understand this.
How does a kite remain airborn? The design of a kite doesn't have the camber of a wing design. Its the angle in relation to the wind that keeps it up.
Everyone has put their arm out the window while riding in a car. Your hand does not have that camber, and yet with the right movement, your hand moves in relation to the angle of attack the wind creates against your hand.

Some Kind Of Monster
11-08-2007, 10:42 AM
Again, noone is arguing aginst the law of aerodynamics.. Well except for the one guy in the other thread..

Racey
11-08-2007, 10:55 AM
No one is disputing aerodynamics here!
the dispute at hand is this:
Will the plane be able to move forward on the treadmill?
the answer is yes!!!!
Think about it like this
1. Chain the plane on the conveyor to the ground.
2. Bring the plane's engines to full power.
3. bring the conveyor speed to 150mph (for arguements sake, average takeoff for a small plane)
4. cut the chain.
Will the plane move forward?
YES!!!!!

superdave013
11-08-2007, 10:57 AM
so how big of a fan would need to be placed in front of said treadmill to get that f'er off the ground??

ULTRA26 # 1
11-08-2007, 11:16 AM
No one is disputing aerodynamics here!
the dispute at hand is this:
Will the plane be able to move forward on the treadmill?
the answer is yes!!!!
Think about it like this
1. Chain the plane on the conveyor to the ground.
2. Bring the plane's engines to full power.
3. bring the conveyor speed to 150mph (for arguements sake, average takeoff for a small plane)
4. cut the chain.
Will the plane move forward?
YES!!!!!
Yep!

Sleek-Jet
11-08-2007, 11:19 AM
As the wing passes through the air, a low pressure area is created on top of the wing and a high pressure area is created under the wing. The combination of the low and high pressure areas lift the wing, which lifts the aircraft.
That all depends on whether you believe an airplane flies because of Bernoulli or Newton.

RiverDave
11-08-2007, 11:20 AM
How someone thinks the plane won't fly is absolutely beyond me.. This is not rocket science here.
The conveyor belt speed only effects "wheel speed." Wheel speed is completely irrelevant in the flying equation.
This is no different then why they have "air speed" and "ground speed" indicators.. A plane can fly at zero mph.. Just like a bird! Ever seen a bird gliding into a head wind and not going anywhere? Ground speed is completely irrelevant to the air plane flying.
Being that the wheels are FREE WHEELING, it doesn't matter how fast the tread mill is going.. If the plane inches forward at 1 mph, the tread mill accelerates to 1mph backwards. The wheels now travel at 2 mph (ground speed), but the air plane still travels forward at 1 mph (air speed, providing no wind).
RD

sigepmock
11-08-2007, 11:33 AM
How someone thinks the plane won't fly is absolutely beyond me.. This is not rocket science here.
The conveyor belt speed only effects "wheel speed." Wheel speed is completely irrelevant in the flying equation.
This is no different then why they have "air speed" and "ground speed" indicators.. A plane can fly at zero mph.. Just like a bird! Ever seen a bird gliding into a head wind and not going anywhere? Ground speed is completely irrelevant to the air plane flying.
Being that the wheels are FREE WHEELING, it doesn't matter how fast the tread mill is going.. If the plane inches forward at 1 mph, the tread mill accelerates to 1mph backwards. The wheels now travel at 2 mph (ground speed), but the air plane still travels forward at 1 mph (air speed, providing no wind).
RD
Word!!!!!!

ULTRA26 # 1
11-08-2007, 12:02 PM
How someone thinks the plane won't fly is absolutely beyond me.. This is not rocket science here.
The conveyor belt speed only effects "wheel speed." Wheel speed is completely irrelevant in the flying equation.
This is no different then why they have "air speed" and "ground speed" indicators.. A plane can fly at zero mph.. Just like a bird! Ever seen a bird gliding into a head wind and not going anywhere? Ground speed is completely irrelevant to the air plane flying.
Being that the wheels are FREE WHEELING, it doesn't matter how fast the tread mill is going.. If the plane inches forward at 1 mph, the tread mill accelerates to 1mph backwards. The wheels now travel at 2 mph (ground speed), but the air plane still travels forward at 1 mph (air speed, providing no wind).
RD
I'm surprized that this everyone doesn't understand this with all of the examples given here.

Halvecta
11-08-2007, 01:19 PM
How someone thinks the plane won't fly is absolutely beyond me.. This is not rocket science here.
The conveyor belt speed only effects "wheel speed." Wheel speed is completely irrelevant in the flying equation.
This is no different then why they have "air speed" and "ground speed" indicators.. A plane can fly at zero mph.. Just like a bird! Ever seen a bird gliding into a head wind and not going anywhere? Ground speed is completely irrelevant to the air plane flying.
Being that the wheels are FREE WHEELING, it doesn't matter how fast the tread mill is going.. If the plane inches forward at 1 mph, the tread mill accelerates to 1mph backwards. The wheels now travel at 2 mph (ground speed), but the air plane still travels forward at 1 mph (air speed, providing no wind).
RD
Nicely done!

ZBODaytona
11-08-2007, 01:25 PM
didn't we go through all this last year!!!!!Oh winter is coming boy are you guys starting early

Some Kind Of Monster
11-08-2007, 02:10 PM
No one is disputing aerodynamics here!
the dispute at hand is this:
Will the plane be able to move forward on the treadmill?
the answer is yes!!!!
Think about it like this
1. Chain the plane on the conveyor to the ground.
2. Bring the plane's engines to full power.
3. bring the conveyor speed to 150mph (for arguements sake, average takeoff for a small plane)
4. cut the chain.
Will the plane move forward?
YES!!!!!
The question doesn't say full throttle does it? Yes it you give it full thrust the fokker will fly like a bat outta hell but that isn't part of the question.

desertbird
11-08-2007, 11:42 PM
...and perhaps this 8 yr old can help you to see that!
http://www.youtube.com/watch?v=-EopVDgSPAk

desertbird
11-08-2007, 11:43 PM
...and perhaps this 8 yr old can help you to see that!
http://www.youtube.com/watch?v=-EopVDgSPAk

Mardonzi
11-08-2007, 11:54 PM
That all depends on whether you believe an airplane flies because of Bernoulli or Newton.
I thought it was Martini and Rossi.....

Ultracrazy
11-08-2007, 11:54 PM
How someone thinks the plane won't fly is absolutely beyond me.. This is not rocket science here.
The conveyor belt speed only effects "wheel speed." Wheel speed is completely irrelevant in the flying equation.
This is no different then why they have "air speed" and "ground speed" indicators.. A plane can fly at zero mph.. Just like a bird! Ever seen a bird gliding into a head wind and not going anywhere? Ground speed is completely irrelevant to the air plane flying.
Being that the wheels are FREE WHEELING, it doesn't matter how fast the tread mill is going.. If the plane inches forward at 1 mph, the tread mill accelerates to 1mph backwards. The wheels now travel at 2 mph (ground speed), but the air plane still travels forward at 1 mph (air speed, providing no wind).
RD
It won't fly..........

sleekcrafter
11-09-2007, 08:25 AM
How fast will my jet boat be on a treadmill:confused: with and with out my truck:D

Kachina26
11-09-2007, 08:40 AM
http://www.grc.nasa.gov/WWW/K-12/airplane/Images/forces.gif
You know, I'm looking at the picture, and I can't find the part about the ground. Drag is produced by the airframe moving through the air. There will be some amount of drag created against the wheels of the plane by the treadmill moving opposite the plane's direction of travel. However, it won't be enough to overcome the thrust created.The wheels contain bearings and grease to reduce that drag. Remember, the plane is moved forward by thrust created by the engine and it's driving device, be it a propeller or a jet turbine, not the wheels. Now if you were trying to get a car with wings to fly, or just get enough speed to lift off of the ground, then it wouldn't happen because the wheels provide forward motion or thrust and they are being counteracted by the treadmill. Bottom line, planes don't need ground speed to fly.