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General Forums => Aces High General Discussion => Topic started by: TonyJoey on February 24, 2009, 09:54:18 PM

Title: Torque
Post by: TonyJoey on February 24, 2009, 09:54:18 PM
Is the torque of an aircraft the same way the prop spins, or opposite which I have always thought it was, based on Newton's Third Law?
Title: Re: Torque
Post by: Lusche on February 24, 2009, 09:57:43 PM
Opposite
Title: Re: Torque
Post by: texastc316 on February 25, 2009, 12:31:33 AM
isnt there a couple of planes that torque the opposite way of the rest ie: tempest? Or am I comfused again?
Title: Re: Torque
Post by: Stoney on February 25, 2009, 12:39:52 AM
isnt there a couple of planes that torque the opposite way of the rest ie: tempest? Or am I comfused again?

Technically speaking, that is not torque--its a characteristic called P-Factor.  But yes, you're correct--Tempest, Spit XIV, etc.
Title: Re: Torque
Post by: texastc316 on February 25, 2009, 12:41:35 AM
thank you sir  :salute
Title: Re: Torque
Post by: BMathis on February 25, 2009, 12:43:17 AM
P-factor, also known as asymmetric blade effect and asymmetric disc effect, is an aerodynamic phenomenon experienced by a moving propeller with a high angle of attack that produces an asymmetrical center of thrust.

 :lol

Title: Re: Torque
Post by: texastc316 on February 25, 2009, 12:46:12 AM
P-factor, also known as asymmetric blade effect and asymmetric disc effect, is an aerodynamic phenomenon experienced by a moving propeller with a high angle of attack that produces an asymmetrical center of thrust.

 :lol



you lost me at hello  :O
Title: Re: Torque
Post by: BMathis on February 25, 2009, 12:51:20 AM
 :D

.........The p-factor is caused by the resultant velocity, which is generated by the combination of the velocity of the propeller blade in its plane of rotation and the velocity of the air passing horizontally through the propeller "disc". with the airplane being flown at positive angles of attack, the right (viewed from the rear) or downswinging blade, is passing through an area of resultant velocity which is greater than that affecting the left or upswiging blade. since the propeller blade is an airfoil, increased velocity means increase lift. Therefore the downswinging blade having more "lift" tends to pull (yaw) the airplane's nose to the left.  Or right with the Yak, Spit14, and Typhs...

Torque Is really described like this:

Torque is the tendency of a force to rotate an object about an axis (or fulcrum or pivot). Just as a force is a push or a pull, a torque can be thought of as a twist.
         Torque is also called moment or moment of force. This should neither be confused with the various other definitions of "moment" in physics nor with "momentum". In the context of mechanical engineering, the terms "moment" and "torque" are not necessarily interchangeable; rather, one or the other may be preferred in a specific context. For example, "torque" is usually used to describe a rotational force down a shaft, for example a turning screw-driver, whereas "moment" is more often used to describe a bending force on a beam.

The magnitude of torque depends on three quantities: First, the force applied; second, the length of the lever arm connecting the axis to the point of force application; and third, the angle between the two.


Ahhhh the wonders of Google  :lol
Title: Re: Torque
Post by: texastc316 on February 25, 2009, 12:53:58 AM
:D

.........The p-factor is caused by the resultant velocity, which is generated by the combination of the velocity of the propeller blade in its plane of rotation and the velocity of the air passing horizontally through the propeller "disc". with the airplane being flown at positive angles of attack, the right (viewed from the rear) or downswinging blade, is passing through an area of resultant velocity which is greater than that affecting the left or upswiging blade. since the propeller blade is an airfoil, increased velocity means increase lift. Therefore the downswinging blade having more "lift" tends to pull (yaw) the airplane's nose to the left.  Or right with the Yak, Spit14, and Typhs...

Torque Is really described like this:

Torque is the tendency of a force to rotate an object about an axis (or fulcrum or pivot). Just as a force is a push or a pull, a torque can be thought of as a twist.
         Torque is also called moment or moment of force. This should neither be confused with the various other definitions of "moment" in physics nor with "momentum". In the context of mechanical engineering, the terms "moment" and "torque" are not necessarily interchangeable; rather, one or the other may be preferred in a specific context. For example, "torque" is usually used to describe a rotational force down a shaft, for example a turning screw-driver, whereas "moment" is more often used to describe a bending force on a beam.

The magnitude of torque depends on three quantities: First, the force applied; second, the length of the lever arm connecting the axis to the point of force application; and third, the angle between the two.


Ahhhh the wonders of Google  :lol


God darnit, Mr. Lamarr, you use your tongue prettier than a twenty dollar hooker


ahh the wonders of Blazing Saddles
Title: Re: Torque
Post by: Cthulhu on February 25, 2009, 10:54:57 AM
:D

.........The p-factor is caused by the resultant velocity, which is generated by the combination of the velocity of the propeller blade in its plane of rotation and the velocity of the air passing horizontally through the propeller "disc". with the airplane being flown at positive angles of attack, the right (viewed from the rear) or downswinging blade, is passing through an area of resultant velocity which is greater than that affecting the left or upswiging blade. since the propeller blade is an airfoil, increased velocity means increase lift. Therefore the downswinging blade having more "lift" tends to pull (yaw) the airplane's nose to the left.  Or right with the Yak, Spit14, and Typhs...

Torque Is really described like this:

Torque is the tendency of a force to rotate an object about an axis (or fulcrum or pivot). Just as a force is a push or a pull, a torque can be thought of as a twist.
         Torque is also called moment or moment of force. This should neither be confused with the various other definitions of "moment" in physics nor with "momentum". In the context of mechanical engineering, the terms "moment" and "torque" are not necessarily interchangeable; rather, one or the other may be preferred in a specific context. For example, "torque" is usually used to describe a rotational force down a shaft, for example a turning screw-driver, whereas "moment" is more often used to describe a bending force on a beam.

The magnitude of torque depends on three quantities: First, the force applied; second, the length of the lever arm connecting the axis to the point of force application; and third, the angle between the two.


Ahhhh the wonders of Google  :lol

Yep  :aok. And yes, what you're feeling at low speed and high throttle is torque. The magnitude which the ailerons need to overcome is a function of the relative rotational inertials of the prop and the rest of the airplane about the thrust axis.

Yaw due to P-factor is secondary, but it can complicate matters, especially if you're slow, pulling high alpha, and decide to really mash the gas pedal. Then the P-factor wants to yaw the aircraft into the wing that's already dropping due to torque, and you could find yourself slow and wings vertical (or inverted), something that really sucks if you're at 50 ft on approach. :uhoh
Title: Re: Torque
Post by: StokesAk on February 25, 2009, 03:20:41 PM
you lost me at hello  :O

1+1=2    :)
Title: Re: Torque
Post by: Ack-Ack on February 25, 2009, 08:45:14 PM
1+1=2    :)

26+26= 42


ack-ack

Title: Re: Torque
Post by: Frodo on February 25, 2009, 08:48:13 PM
26+26= 42


ack-ack



 :noid  :rofl  :aok    Gunman26

And I thought this was a thread on a long ago F4u dweeb!   :noid  :noid

Frodo
Title: Re: Torque
Post by: TonyJoey on February 25, 2009, 08:49:29 PM
26+26= 42


ack-ack



 :rofl That was hilarious

BTW, thx snail

PS: Go Gutless Gastropods!
Title: Re: Torque
Post by: Tilt on February 26, 2009, 06:18:33 AM
i liked HT's definition better..............

Quote
1. Torque. a rolling force.
2. Slip stream, produces both roll force oposit torque  and yaw force.
3. P Factor produces both pitch and yaw forces.
4. Gyroscopic both pitch and yaw forces.

Torque by itself does not produce a yaw tendency, only a roll, as straiga describs it does produce a secondary yaw force do to increase load on 1 tire but this is very minor force.

The major force involved when starting a take off roll is only slip stream.

P factor and gyro, do not have any effect at the start of a take off roll.

Torque is computed simply

(Current HP) / RPM * 5252

Also torque is produce fairly linar to the throttle setting and is effected very little by the engine speeding up or slowing down.

HiTech
Title: Re: Torque
Post by: hitech on February 26, 2009, 08:27:34 AM
Torque is when you wake up in the morning and have to pee really bad. You go to the toilet, push it down, and your feet fly off the floor.


HiTech
Title: Re: Torque
Post by: Stampf on February 26, 2009, 08:29:14 AM
 :rofl
Title: Re: Torque
Post by: ImADot on February 26, 2009, 08:32:46 AM
 :rock
Title: Re: Torque
Post by: Frodo on February 26, 2009, 09:16:53 AM
 :D   
Title: Re: Torque
Post by: Masherbrum on February 26, 2009, 02:11:46 PM
 :O
Title: Re: Torque
Post by: Tec on February 26, 2009, 02:18:23 PM
Torque is when you wake up in the morning and have to pee really bad. You go to the toilet, push it down, and your feet fly off the floor.

Wouldn't that be thrust?  I'm pretty sure torque is what causes you to miss the toilet towards whatever direction your dominant hand is when you don't hold it on target.
Title: Re: Torque
Post by: Cthulhu on February 26, 2009, 02:26:36 PM
Torque is when you wake up in the morning and have to pee really bad. You go to the toilet, push it down, and your feet fly off the floor.


HiTech
HiTech: Master of the "Forward Kickstand Somersault".
(or as it's know in Gymnastic's circles: the "Triple Forward Woody from the Untucked Position")
Title: Re: Torque
Post by: Murdr on February 27, 2009, 06:30:25 PM
Wouldn't that be thrust?  I'm pretty sure torque is what causes you to miss the toilet towards whatever direction your dominant hand is when you don't hold it on target.

That's what I enjoy about the AHBBs.  Technical discussions on almost any topic. (http://bbs.hitechcreations.com/smf/index.php/topic,156464.msg1755379.html#msg1755379) 
Title: Re: Torque
Post by: Wingnutt on February 27, 2009, 07:34:59 PM
Torque is when you wake up in the morning and have to pee really bad. You go to the toilet, push it down, and your feet fly off the floor.


HiTech

 :confused:
..... You need to get your prostate checked
Title: Re: Torque
Post by: Cobra516 on February 27, 2009, 07:51:04 PM
You also have the gyroscopic precession effect of the propeller - that is also trying to yaw the airplane to the left.  That 12 ft long, 4 bladed prop in something like a '51 is quite a powerful gyroscope.

That's why the nose wants to yaw further to the left as you raise the tail - the force is being applied at the 12 o' clock - but it is felt 90 degrees in the direction of rotation - so at the 3 o'clock position (from the pilots viewpoint). 

Airplanes like Spit 14, have the prop / engine turning in the opposite direction, so the forces (except for torque, which is trying to go opposite the direction of rotation) are trying to yaw it to the right.
Title: Re: Torque
Post by: ImADot on February 27, 2009, 09:31:53 PM
Oh, sure...way to bring the thread back on topic.  :lol