I was a gyro compass technician in the Navy many decades ago. Your explanation of rigidity in space and precession brought back many old and valid memories.
The gyro effect only comes into play when the attitude is changed and is different if you pitch up or down. It is a left turning tendency when you pitch down. This is mostly prevalent in a tail dragger aircraft on it's initial take off roll as it gains speed. When you pitch down slightly to bring the tail off of the runway, a force is applied at the 12 o'clock position to the tip of the "spinning disk" prop. This force (thrust) is then felt 90 degrees later and rotates the aircraft to the left. It is a right turning tendency when you pitch up. So in a tricycle gear aircraft when you pitch up on rotation the force is applied to the bottom of the "spinning disk" prop and the force is felt 90s later and pulls the aircraft to the right. Overall though, the gyro effect isn't a big one and you still, of course, have the other three overpowering it and causing aircraft to yaw left at high power, slow airspeed, and high pitch situations. It is a big deal when you're brining the tail off the ground in a tail dragger aircraft. You'll have more left turning tendencies as compared to a tricycle aircraft.
Gyroscopic precession is a right turning tendency during pitch up and left during pitch down. The video presents this incorrectly, or vaguely at best: it lumps it up with the other 3 left turning factors and does not distinguish the role the direction of the pitch plays in which way the nose turns.
You are correct. However it also depends which way the propeller spins about it’s axis. It will be a left turning tendency if it’s a counter clockwise prop.
I never settled for just calling it P-factor for the collection of phenomena, but I know why some do. Great presentation articulating the important differences.
Gyroscopic precession isn’t a left turning tendency on takeoff for a tricycle landing gear airplane.... it’s a right turning tendency that helps cancel the others.
Getting ready for my commercial check ride, this really helps! Something worth mentioning is when the 4 left turning tendencies are likely to occur-- high power settings and lower airspeeds!
Excellent video! However, I have always wondered why gyroscopic precession is considered to be a LEFT turning tendency on takeoff. It can easily be demonstrated with a handheld gyroscope that it precesses to the RIGHT: 1. Hold the gyroscope on one pole. Your hand is the airplane. 2. Spin the gyroscope clockwise in relation to your hand, as the propeller spins in relation to the plane. 3. Tilt the gyroscope upward, in the relative direction of takeoff. The gyroscope precesses to the RIGHT!
Two things wrong in this video. Gyroscopic precession is not a left turning tendency in a climb as would be with all the the others. It’s a left turning tendency when u apply a force at the top such as raising the tail. Second I think he said the force will be felt ahead in the “opposite” direction. It’s felt ahead in the direction of rotation
Hey Jason, I am in love with the new way you’re doing your video here inside the shop. The simulated graphics it’s beautiful along with the graphical work off showing directional flow of air and the airfoils. Also love the fact that you’re model airplane is actually your airplane painted up looking beautiful. You have just stepped your content up another notch man. Thank you so much. I learn so much from you. - Big fan
Exactly. The forces applied to the gyro (propeller disc) are during pitch up and pitch down, regardless of the type of aircraft. On a tailwheel during takeoff, it is equivalent to a pitch down (tail up). From cockpit, on pitch down, a force is applied on the propeller at 12 o’clock (from behind), felt at 3 o’clock (from behind) causing a left tending tendency; on pitch up it is at 6 o’clock and felt at 9 o’clock for a right tending tendency.
Gyroscopic Precession can be felt if you do power on incipient stall practice. It is when the stall horn sounds (after high angle of attack) with full throttle and then you put your pitch down to horizon (climbing attitude), your plane will have left turning tendencies.
Banking to the right also has a left turning tendency, as strange as that sounds. While banking in straight and level flight, the ascending wing has more lift than the decending wing which causes it to also have more drag and thus yaw to the direction of the acceding wing. Similarly, after the bank angle is established and the ailerons are neutral the airplane is turning. The outside wing in the turn is going faster than the inside wing in the turn, causing more lift and hence more drag on the outside wing making the aiplane yaw in that direction. Its amazing how much one action can have multiple effects
Thanks for this reminder however I'd like to know if as a pilot we can sense, identify and differentiate each one of these 4 tendencies in a separate way while performing a manoeuvre. Cheers
On torque effects the plane has a rolling motion about longitudinal axis, the wing will rise but we can’t turn to close ground. A moment is transferred to left wheel also adding to left turning tendency. Correct me if I am wrong with my statement,
Like others have said there's misinformation here. When pitching up gyroscopic forces create a right turning tendency. And also, the torque effect creates a left bank, not a left yaw.
P-factor explanation was not good. It only takes a bigger bite when the plane is more elevated than the direction it's going. Actually: anytime the direction of the plane velocity is not exactly anti-parallel with the direction of the airflow you have a p-factor. Which can result in either a left-, right-, up or down turning tendency.
Newton's third law is not about action and reaction, but about forces. Torque is not a force and mathematically it is a axial vector, not the type of force. For example, in a mirror the two reflect differently. Hence a reaction to a torque is not apposite, but in a different direction, according to the inertial tensor and not to the scalar mass. I'll be back when you correct the Physics of you exposition.
If my students have memorized and understand left turning tendencies, I'll always ask them this question to make sure they can apply and correlate that knowledge. Would you prefer a right or left crosswind?
Is the slipstream really helical? I can't think why it should be. Perhaps the air immediately behind the propeller has a rotational moment, but once it gets a foot or two back, why would it continue in a helical path? What's containing the helix? Why wouldn't its centrifugal tendency just give it a bit of an outward vector for a moment, perhaps creating a slight low-pressure region around the engine cowling? Imagine a charge of birdshot fired from a shotgun with a rifled barrel. You might imagine the birdshot continuing to travel in a helical pattern as it flies downrange, preserving the spin it picked up from the rifling, but that's not what happens. Inside the barrel, the shot is contained and forced to move helically by the shot cup and the barrel; but at the muzzle, the spin serves only to fling the shot pattern wider than a smoothbore pattern would be, and to introduce a doughnut-hole in the center of the pattern. The shot doesn't fly helically, it flies straight (aside from the force of gravity), after its centrifugal vector gives it a little extra eccentricity from the axis of the barrel. Seems to me something similar would happen to air coming off a propeller. How do we actually _know_ slipstreams are helical? Could this be a widely-accepted old wives' tale? Is there video somewhere showing helical smoke in a wind tunnel?
I fly a avid mk5 with a ea81 aircraft engine and turns opposite of a regular aircraft engine and neutralizes most of this problem. I mostly fly out with a natal rudder except compensation for side wind. I don't get why all small aircraft don't turn the opposite way that they do!
hmm the torque from the spinning blade does not directly cause a yaw moment, but rather causes a roll moment which is converted into a yaw moment through the increased friction on the left wheel of the plane...correct?
That's correct. That's why if you fly a four seater and have only one passenger for the back seat, he should sit in the right seat to compensate for the increased load/drag on the left tire due to torque. I'm joking.
Hello torque do not force the air craft to the left .just try to rotate the fuselage to the left, increasing lift on the Right wing, turning the aircraft to the left. On run-up increase power and decrease power rapidly and find a harmonious point the wings will move up and down . Is very funn.saludos
Okay this is 3rd video with unclear explanation... Mostly about torque - this is not a helicopter - the propeller is rotating vertically, not horizontally - it causes some pitch, but how this pitch is translated into yaw?
No, you are not stupid. The explanation is wrong. The rotating bodies do not react like vectors, i.e. along the line of some force, but like tensors...
Other than precision and keeping the plane tracking on the centerline. Is there any danger during the climb out and relatively slow speeds. Without rudder compensation the plane is in uncoordinated condition. Hmmm...Did I just answer my own question? If stall then spin? Confirm if you would that I finally got the concept
Hi Neal! Thanks for commenting. Yes! You totally understand the concept. In an uncoordinated condition at high angles of attack and low airspeeds, you have a recipe for an aggressive stall that can turn into a spin. Hope this helps! If you need anything else please reach out to us at support@mzeroa.com. Fly safe!
At best rate of climb airspeed, you're nowhere near a stall. Probably the only consequence of climbing with the ball a little out of center is a little drag because you're in a slip, resulting in a slower climb.
Can you explain further why torque creates a left turning tendency on the initial part of the take off roll? The opposite of the engine torque applied to the propeller is torque to the airframe along the longitudinal axis. In flight this will create a roll to the left, which if uncorrected, will turn the aircraft to the left. But, I don't understand how this translates to a left turning tendency on the takeoff roll.
John Cessna well from my understanding when you apply full power on takeoff the torque effect while its Primary effect is a roll it’s Secondary effect is to cause a yaw from the friction on the left wheel on the ground while accelerating , so similar to if you were to apply left the left brake while accelerating on the runway.
Beautiful looking graphics and animation but the content wasn't very well explained. P-factor should have been explained with the propeller disc tilted fore/aft to accurately show the changing relative wind and the asymmetric disc loading (you better actually understand this when you try to fly a taildragger), the graphics did a poor job of explaining this, torque is a rolling moment to the left (depending on the propeller rotation - on some pusher aircraft the roll is to the right), and torque isn't much of a factor on a 172 pulling you to the left on roll (due to the downward pressure on the left main) but spiraling slipstream is, the overhead drone shot would have been better placed at that point supported with the slipstream graphic. I won't even comment on gyroscopic precession. Maybe less time at the gym and more time polishing the content. Good effort but I'd read the PHAK and AFH to get the entire story.
It seans like he remembers the words but has no idea how it really works Very poor explanation The Newton 3th law for every action there is an equal and opposite action.. granted but it does not create a yaw effect to the left like he explained, torque factor creates a roll effect to the left, the lack of air flowing on the wings the plane rolls to the left releasing pressure on the right tire and adding pressure on the left tire therefore creates a left turn. The p factor is missing relevant details to a better understanding The p factor has no effect on the ground or level flight. In a foward motion both blades have the exact angle of attack producing the same amount of thrust so this does not effect the takeoff When the plane climbs the propeller shaft is no longer perpendicular to the flight path , at this moment the down going blade has a greater angle of attack in additional the down going blade travels faster producing more thrust causing a left yaw
I was a gyro compass technician in the Navy many decades ago. Your explanation of rigidity in space and precession brought back many old and valid memories.
The gyro effect only comes into play when the attitude is changed and is different if you pitch up or down. It is a left turning tendency when you pitch down. This is mostly prevalent in a tail dragger aircraft on it's initial take off roll as it gains speed. When you pitch down slightly to bring the tail off of the runway, a force is applied at the 12 o'clock position to the tip of the "spinning disk" prop. This force (thrust) is then felt 90 degrees later and rotates the aircraft to the left. It is a right turning tendency when you pitch up. So in a tricycle gear aircraft when you pitch up on rotation the force is applied to the bottom of the "spinning disk" prop and the force is felt 90s later and pulls the aircraft to the right. Overall though, the gyro effect isn't a big one and you still, of course, have the other three overpowering it and causing aircraft to yaw left at high power, slow airspeed, and high pitch situations. It is a big deal when you're brining the tail off the ground in a tail dragger aircraft. You'll have more left turning tendencies as compared to a tricycle aircraft.
Gyroscopic precession is a right turning tendency during pitch up and left during pitch down. The video presents this incorrectly, or vaguely at best: it lumps it up with the other 3 left turning factors and does not distinguish the role the direction of the pitch plays in which way the nose turns.
You are correct. However it also depends which way the propeller spins about it’s axis. It will be a left turning tendency if it’s a counter clockwise prop.
I never settled for just calling it P-factor for the collection of phenomena, but I know why some do. Great presentation articulating the important differences.
Just went over this today in class, you made it very simple to understand and remember. Cheers
Finally an Instructor that is so great to explain very clear that ! thank you a lot !
Glad it was helpful!
Gyroscopic precession isn’t a left turning tendency on takeoff for a tricycle landing gear airplane.... it’s a right turning tendency that helps cancel the others.
Correct. It is a left turning tendency if you are pitching down.
Yes, such as when lifting the tail on a taildragger.
LordRawnsley Correct!
pitch down, precession left. yaw left, precession up. pitch up, precession right. yaw right, precession down :)
correct. the force is 90 degrees ahead in the direction of rotatiion
Getting ready for my commercial check ride, this really helps! Something worth mentioning is when the 4 left turning tendencies are likely to occur-- high power settings and lower airspeeds!
Excellent video! However, I have always wondered why gyroscopic precession is considered to be a LEFT turning tendency on takeoff. It can easily be demonstrated with a handheld gyroscope that it precesses to the RIGHT: 1. Hold the gyroscope on one pole. Your hand is the airplane. 2. Spin the gyroscope clockwise in relation to your hand, as the propeller spins in relation to the plane. 3. Tilt the gyroscope upward, in the relative direction of takeoff. The gyroscope precesses to the RIGHT!
Two things wrong in this video. Gyroscopic precession is not a left turning tendency in a climb as would be with all the the others. It’s a left turning tendency when u apply a force at the top such as raising the tail. Second I think he said the force will be felt ahead in the “opposite” direction. It’s felt ahead in the direction of rotation
Hey Jason, I am in love with the new way you’re doing your video here inside the shop. The simulated graphics it’s beautiful along with the graphical work off showing directional flow of air and the airfoils. Also love the fact that you’re model airplane is actually your airplane painted up looking beautiful.
You have just stepped your content up another notch man.
Thank you so much. I learn so much from you.
- Big fan
All of these videos are amazing!!! Thank you guys for all your hard work and effort in making these so easy to understand for a beginner!
Thanks so much for watching!
Very helpful explanation Jason. Thank you.
Hello Gyroscopic Precession the force follow the same direction of rotation. In you explanation you mentioned in the opposite direction. Saludos
pavelavietor1 I noticed that too !
Yup he said I’d wrong
tail dragger turns left , tricycle gear airplane turns To right
Exactly. The forces applied to the gyro (propeller disc) are during pitch up and pitch down, regardless of the type of aircraft. On a tailwheel during takeoff, it is equivalent to a pitch down (tail up). From cockpit, on pitch down, a force is applied on the propeller at 12 o’clock (from behind), felt at 3 o’clock (from behind) causing a left tending tendency; on pitch up it is at 6 o’clock and felt at 9 o’clock for a right tending tendency.
"certainly this video is more suitable for a private pilot"... and I'm very happy !!!!! Thanks for your videos 👍👍👍👍
Thanks for the explanation Captain 👨✈️ you really have taught me a lot with your explanations in your videos
Sean Mugala it is interesting!
I believe gyroscopic precession isn't felt 90 degrees in the opposite direction, but in the direction of the rotation.
Gyroscopic Precession can be felt if you do power on incipient stall practice. It is when the stall horn sounds (after high angle of attack) with full throttle and then you put your pitch down to horizon (climbing attitude), your plane will have left turning tendencies.
Thanks for the feedback!
"And remember: a good pilot is always learning! See you next time, your captain Joe."
you just know how to many stuff more easier. A big thanks to you
This is so great! I love this channel, because it made me like aviation more plus, it helps me prepare myself for flight school! Thanks a lot! :D
Awesome video Jason, I listen to the podcast every morning (Left turning tendencies on repeat)
P.S. Nice Gains Brah!
I always mentioned the turning "tendencies" as forces since there is no "tendency" to turn left and it is fact that those forces do happen.
Banking to the right also has a left turning tendency, as strange as that sounds. While banking in straight and level flight, the ascending wing has more lift than the decending wing which causes it to also have more drag and thus yaw to the direction of the acceding wing. Similarly, after the bank angle is established and the ailerons are neutral the airplane is turning. The outside wing in the turn is going faster than the inside wing in the turn, causing more lift and hence more drag on the outside wing making the aiplane yaw in that direction. Its amazing how much one action can have multiple effects
Is this adverse yaw?
I, personally, have never heard someone call all 4 of them P-Factor, I just hear them called what they are
Thanks for this reminder however I'd like to know if as a pilot we can sense, identify and differentiate each one of these 4 tendencies in a separate way while performing a manoeuvre.
Cheers
On torque effects the plane has a rolling motion about longitudinal axis, the wing will rise but we can’t turn to close ground. A moment is transferred to left wheel also adding to left turning tendency. Correct me if I am wrong with my statement,
P-factor is an issue when the propeller blade disc is tilted backwards, so in a climb and with taildraggers. In level flight its no issue
flexairz or whenever the AOA is high regardless of the mode of flight.
flexairz not exactly,at level flight,P-factor will let aircraft has the tendency of right bank.
Thanks just the info I was looking for torque direction on power up.
Glad you liked it!
Like others have said there's misinformation here. When pitching up gyroscopic forces create a right turning tendency. And also, the torque effect creates a left bank, not a left yaw.
Technically, a left roll, but you're mostly correct. This is often misunderstood and mistaught.
Talks about gyroscope precession and how difficult it is to understand and moves on after still not making it not difficult to understand
I hate when people take one karate class and then opens up a school and calls himself a master instructor
extremely helpful！！！ thank you！！！
Very nice video!!!, Thank you very much
Glad you liked it! Thank you for watching!
Hi thankyou for your great info👌 despite of the topic , i fall in love with that littel cessna (a model airplane) .😍that you taught us with it .
thank you my guy
Gyroscopic precession is explained in a wrong way. It will yaw left only on a taildragger. Please fix it.
so basically just state these 4 tendencies when been asked and you are good ? Cuz I still can't get Gyroscopic
It’s a pretty bad video tbh. P factor should be shown with a propeller at an angle anyway.
The word tendency is wrong which used by FAA, because tendency it means it doesn't happen always, but these are always happen.
If the word tendency is wrong, what word would be better?
P-factor explanation was not good.
It only takes a bigger bite when the plane is more elevated than the direction it's going.
Actually: anytime the direction of the plane velocity is not exactly anti-parallel with the direction of the airflow you have a p-factor. Which can result in either a left-, right-, up or down turning tendency.
Thanks for the feedback, Job.
Thank you Jason, very interesting 👍🏻
Newton's third law is not about action and reaction, but about forces. Torque is not a force and mathematically it is a axial vector, not the type of force. For example, in a mirror the two reflect differently. Hence a reaction to a torque is not apposite, but in a different direction, according to the inertial tensor and not to the scalar mass. I'll be back when you correct the Physics of you exposition.
pfactor is left tendency only on tailwheel
So does the "P" stand for "pedal", since you have to use the pedal for any/all of them?
What an explanation sir! 😊
Glad you liked it! Thanks for watching!
If my students have memorized and understand left turning tendencies, I'll always ask them this question to make sure they can apply and correlate that knowledge. Would you prefer a right or left crosswind?
Is the slipstream really helical? I can't think why it should be. Perhaps the air immediately behind the propeller has a rotational moment, but once it gets a foot or two back, why would it continue in a helical path? What's containing the helix? Why wouldn't its centrifugal tendency just give it a bit of an outward vector for a moment, perhaps creating a slight low-pressure region around the engine cowling?
Imagine a charge of birdshot fired from a shotgun with a rifled barrel. You might imagine the birdshot continuing to travel in a helical pattern as it flies downrange, preserving the spin it picked up from the rifling, but that's not what happens. Inside the barrel, the shot is contained and forced to move helically by the shot cup and the barrel; but at the muzzle, the spin serves only to fling the shot pattern wider than a smoothbore pattern would be, and to introduce a doughnut-hole in the center of the pattern. The shot doesn't fly helically, it flies straight (aside from the force of gravity), after its centrifugal vector gives it a little extra eccentricity from the axis of the barrel.
Seems to me something similar would happen to air coming off a propeller. How do we actually _know_ slipstreams are helical? Could this be a widely-accepted old wives' tale? Is there video somewhere showing helical smoke in a wind tunnel?
Really good info. I was only familiar with torque factor.
Great Video!
Good job Jason
I fly a avid mk5 with a ea81 aircraft engine and turns opposite of a regular aircraft engine and neutralizes most of this problem. I mostly fly out with a natal rudder except compensation for side wind. I don't get why all small aircraft don't turn the opposite way that they do!
Really A Great Video,Thank You!!
Thank you so much for this! 😊
Thank you so much very useful video
hmm the torque from the spinning blade does not directly cause a yaw moment, but rather causes a roll moment which is converted into a yaw moment through the increased friction on the left wheel of the plane...correct?
Hi Adam, that is correct! Thanks for watching!
That's correct. That's why if you fly a four seater and have only one passenger for the back seat, he should sit in the right seat to compensate for the increased load/drag on the left tire due to torque.
I'm joking.
Hello torque do not force the air craft to the left .just try to rotate the fuselage to the left, increasing lift on the Right wing, turning the aircraft to the left. On run-up increase power and decrease power rapidly and find a harmonious point the wings will move up and down . Is very funn.saludos
pavelavietor1 Primary effect of Torque Reaction is a Roll. The Secondary effect is a yaw due to the friction acting on the left wheel
jupiterscock1 tu you are correct but the video is about the left turning tendency of a reciprocating engine fix wing air craft saludos
Okay this is 3rd video with unclear explanation...
Mostly about torque - this is not a helicopter - the propeller is rotating vertically, not horizontally - it causes some pitch, but how this pitch is translated into yaw?
Help. I’m stupid. If the propeller is turning in the right direction, then why is it yawing towards the left???
No, you are not stupid. The explanation is wrong. The rotating bodies do not react like vectors, i.e. along the line of some force, but like tensors...
Other than precision and keeping the plane tracking on the centerline. Is there any danger during the climb out and relatively slow speeds. Without rudder compensation the plane is in uncoordinated condition. Hmmm...Did I just answer my own question? If stall then spin? Confirm if you would that I finally got the concept
Hi Neal! Thanks for commenting. Yes! You totally understand the concept. In an uncoordinated condition at high angles of attack and low airspeeds, you have a recipe for an aggressive stall that can turn into a spin. Hope this helps! If you need anything else please reach out to us at support@mzeroa.com. Fly safe!
At best rate of climb airspeed, you're nowhere near a stall. Probably the only consequence of climbing with the ball a little out of center is a little drag because you're in a slip, resulting in a slower climb.
Will some forces cancel each other?
What about for jet-engine planes? Is there any tendency for the plane to turn left?
Do all these left turning tendencies only apply to tailwheel airplane?
Thank you sir
Can you explain further why torque creates a left turning tendency on the initial part of the take off roll? The opposite of the engine torque applied to the propeller is torque to the airframe along the longitudinal axis. In flight this will create a roll to the left, which if uncorrected, will turn the aircraft to the left. But, I don't understand how this translates to a left turning tendency on the takeoff roll.
John Cessna well from my understanding when you apply full power on takeoff the torque effect while its Primary effect is a roll it’s Secondary effect is to cause a yaw from the friction on the left wheel on the ground while accelerating , so similar to if you were to apply left the left brake while accelerating on the runway.
Where can you get a download of 523MZ for the sim? Nice Video by the wat
Beautiful looking graphics and animation but the content wasn't very well explained. P-factor should have been explained with the propeller disc tilted fore/aft to accurately show the changing relative wind and the asymmetric disc loading (you better actually understand this when you try to fly a taildragger), the graphics did a poor job of explaining this, torque is a rolling moment to the left (depending on the propeller rotation - on some pusher aircraft the roll is to the right), and torque isn't much of a factor on a 172 pulling you to the left on roll (due to the downward pressure on the left main) but spiraling slipstream is, the overhead drone shot would have been better placed at that point supported with the slipstream graphic. I won't even comment on gyroscopic precession. Maybe less time at the gym and more time polishing the content. Good effort but I'd read the PHAK and AFH to get the entire story.
Very nice.
I never understood why my RC helicopter rotor head was set up the way it was. Now I know that it’s because of gyroscopic precession!
You have the same learn to fly poster I have haha.
Awesome! Thanks for watching!
Thank you so much!! this is a great explanation!
Love it....
what a video
what is them music used in the end of the video please.
Thank you for the great explanation of the turning tendencies
fuck this guy is hot, and very wholesome sounding
It seans like he remembers the words but has no idea how it really works
Very poor explanation
The Newton 3th law for every action there is an equal and opposite action.. granted but it does not create a yaw effect to the left like he explained, torque factor creates a roll effect to the left, the lack of air flowing on the wings the plane rolls to the left releasing pressure on the right tire and adding pressure on the left tire therefore creates a left turn.
The p factor is missing relevant details to a better understanding
The p factor has no effect on the ground or level flight. In a foward motion both blades have the exact angle of attack producing the same amount of thrust so this does not effect the takeoff
When the plane climbs the propeller shaft is no longer perpendicular to the flight path , at this moment the down going blade has a greater angle of attack in additional the down going blade travels faster producing more thrust causing a left yaw
There are five, not four!!
OK. I'll bite. What's the fifth?
This guy was wrong about almost every single thing. He's clueless.
Well his explanation about spiraling slipstream was correct.
I know what I gonna say is irrelevant, but the host is sooo hot..lol