Propeller Effects.

#shorts
Learn more about this topic in these videos:
• What is P-FACTOR? | Th...
• Why is the aircraft pr...
• Asymmetrical Marvels Y...

[@PhlyBoy_135]

My instructor never explained why the aircraft yaws on take off I just assumed it was to engine torque, thanks for telling me the real reason 👍

[@ericstyles3724]

Displaced torque, you're kinda right there.

[@jakobusstrauss1293]

If you are flying a tricycle gear plane then torque is about the only factor causing a yaw to the left, up until the point of rotation. Once you rotate P-factor occurs. On conventional gear planes P-factor sets in almost immediately until the tailwheel is rotated off the ground then diminishes. Basically anytime the plane is at a high AoA and power setting P-factor will occur.

[@managed9348]

Me too

[@mrmaniac3]

Torque would be roll rather than yaw I think, but yep that's p-factor :)

[@drgeorgek]

What a worry your instructor first even one this basic physics concept

[@jambooski1836]

Finally! A good visual I can show my students. You earned a sub from a CFII

[@maximillianscholtz9109]

I know right its sad that not enough KZbin content that could be great for education is used for that. And getting a visual representation makes it so much easier to understand than if you just have a teacher talking. Sorry for going on a rant😅

[@JAXKILLER02]

Which flight school? If it’s not much to ask..

[@Wingman77tws]

The conclusion here is wrong, you need rudder on takeoff because counteracting the torque of the propeller uses aileron, and the drag of the aileron causes a yaw torque on the aircraft. As for the right side of the propeller having more lift, that is true, but due to gyroscopic procession, that torque is actually a pitch up not a left yaw.

[@cartertran270]

And now I know why I have to rudder some much on take off. 👌

[@muhammadjalal2335]

Yo

[@MrT------5743]

Helicopters also have an issue similar. The faster they are moving forward. The advancing side of the main rotor gets more lift than the retreating side of the main rotor. Then, the power stopping procession causes that change in force to be applied 90° around the spin axis.

[@jakobusstrauss1293]

This is called the Dissymetry of lift. Not really the same issue, but simmilar effect. The reason it happens is because you have an advancing blade ( the blade going in the same direction the helicopter is travelling) and a retreating blade ( the one going in the opposite direction in which the heli is travelling). Blades need airspeed to produce lift. More airspeed = more potential lift. The one going in the same direction of travel as the helicopter will have an effective airspeed which is equal to its own movement plus the forward speed of the whole helicopter. On the other side the retreating blade will have an effective airspeed equal to its own movement minus the helicopter's forward speed. Thus the two sides are producing unequal lift. The faster the heli flies, the greater the effect. This can be compensated for during its normal flight envelope, however when a heli reaches the critical airspeed where the retreating blade can no longer produce enough lift it will stall and its lift will dramatically reduce. This produces a large inbalance in lift. The force is displaced by 90° in the direction of rotation of the blades and causes the nose of the heli to pitch up violently. This phenomenon is called retreating blade stall. Basically it stalls because it flew too fast.

[@jackcobb1090]

That's why helis have speed limits. Eventually the retreating blade stalls completely.

[@snjert8406]

​@@jackcobb1090that sounds terrifying.

[@kambalekabanda]

So how to fix this problem?

[@randomguyontheinternet6885]

Does double rotor helicopter have this issue?

[@SirRobertSpriggs]

That's why the P-38 was a great plane. One prop went counterclockwise, and the other clockwise (blades flipped too) created very good stability.

[@cmilburn26]

That is how every single twin prop aircraft works. Aztecs, Barons, P-38’s etc. The issue at hand only applies to single prop aircraft, which would eliminate the P-38.

[@RomeoWhiskeyTango]

⁠@@cmilburn26. Actually, that’s not always the case. There are many multi-engine aircraft that DO NOT have counter-rotating engines and propellers- including ones you mentioned. This is why such aircraft are deemed to have a critical engine with respect to aircraft handling in the case of an engine failure. www.faasafety.gov/files/notices/2015/Nov/FAA_P-8740-66.pdf

[@HotelPapa100]

@@cmilburn26 Nope. Most twins have same sense rotating props. Too expensive to build engines for both senses of rotation. That's why twins have a so called 'critical engine'. If that fails, the P-factor of the remaining engine acts outboard, giving an even greater asymmetry of thrust. Except the P-38. They chose sense of rotation of the props such, that the P-38 had TWO critical engines...

[@egor_flips]

It’s not for nothing that they put an even number of turbojet engines on an airplane: 2, 4, 6, 8, 12 on very heavy airplanes

[@hunormagyar1843]

​@@egor_flipsYou could say that, but there are a number of exceptions. Ju-52, Ford Trimotor, numerous Italian ww2 bombers, or the Lockheed Tristar to name a few.

[@David-lb4te]

Right, except the end. The video assumes the propeller rotates clockwise (viewed from behind). For anti-clock rotation the effect is reversed, and rudder use would be opposite. This was the first effect a Spitfire pilot experienced when moving from Merlin to Griffon powered Spitfires, as the Griffon rotates opposite to the Merlin.

[@homestyle2000]

very good information, is there a predominant rotation that most planes use or its it a fairly even split?

[@David-lb4te]

@@homestyle2000 US engines tend to rotate clockwise (when viewed from the rear). British engines tend to rotate anti-Clockwise (eg Bristol Hercules). Except the Merlin! There is no fixed rule though.

[@JTMarlin8]

@@David-lb4te Good to know! I'm going to the Supermarine dealership tomorrow and will probably order the Merlin.

[@hamsterbuilder7796]

⁠@@JTMarlin8I assume you are sarcastic. Pretty sure the Merlin engine was produced by Rolls Royce too.

[@cartertran270]

I’m assuming that with twin props they do one of each and they cancel each other out?

[@microtheguyfromearth]

So now i know why i cant take off straight in simulator battles

[@Timothyyyy.photog]

Attack the D Point!

[@ondrejkviz9653]

Attack the D point!

[@pawanrohidas1163]

Gotta use the rudder while takeoff and slowly increasing throttle and go in a straight line slowly then increase speed so you won't spin out the moment you hit full throttle

[@navyguy6099]

Same shit bro😂😂😂😂😂😂

[@markdaniel8740]

Even more complex than that. The air does not flow in a straight line, but in a spiral. It will hit the left side of the vertical stabilizer more directly than the right, thus acting like it is being given left rudder.

[@pilotkiwi5000]

I didn't know this, that's really interesting

[@infotechsailor]

In flight school we called it the left turning tendencies. P factor also includes air hitting the tail

[@homestyle2000]

you should also look at adverse yaw. its the yawing effect that using the ailerons cause and the reason why coordinated turns are a difficult skill to develop for some pilots.

[@jakobusstrauss1293]

​@@infotechsailorYou are referring to two different effects. P-factor is what is explained in the video. The slipstream effect is due to the spiralling propeller slipstream hitting the vertical surface of the plane (usually the vertical stab) on only one side, thus pushing it in a direction and yawing the nose in the opposite direction. The existance of the slipstream effect has been debated by aerodynamicists.

[@DanSlotea]

As far as I know, it's a combination of torque, spiraling slipstream, P-factor, and gyroscopic precession, not just the P-factor that turns the plane to the left for a clockwise rotating engine.

[@CapybaraSociety]

i don’t know who you are, or where you live but we got beef now

[@soisaus564]

And can't forget the most obvious problem with singular propellers is that the propeller itself is constantly pushing the whole plane to rotate to the opposite direction of wherever the propeller is turning at.

[@av8tore71]

They call that P factor which is why you hold right rudder on take off

[@beastlymace2214]

well, one of the many

[@fulcrum2951]

Depending on propeller rotation

[@snjert8406]

​@@fulcrum2951this

[@dinikcr8498]

Wow, something actually interesting and easy to understand❤

[@flightclubonline]

Glad you think so!

[@Mojemoye]

​@@flightclubonline Hey your voice is beautiful and soothing, I want to see you🤍

[@davethurley3006]

The spiral effect of the propeller wash on the tail gives planes more of a swing

[@jakobusstrauss1293]

Not really. P-factor and torque and gyroscopic precession are the largest forces. The existance of spiral propeller slipstream has been debated.

[@dsmkyle8802]

So why do they turn on the ground also if its the angle of attack when the planes level on the ground? The blades are spinning fast air moving fast wouldnt that push on the vertical stabilizer no matter what even level? This guys comment makes more sense then yours and tons of other peoples. Js

[@ziggynutscmgoofy]

So thats why my plane in war thunder turns left during takeoff

[@sraLLars]

"By pointing the propeller slightly to the right, this effect is offset a little and the aeroplane becomes more balanced." I still come back to that video sometimes, just to calm my mind ❤

[@tomsparks3259]

This explaination makes much more sense than what I was supposed to learn in training.

[@Martin-kv3th]

this is so noticeable that when i don’t push the right pedal down i WILL move left

[@hjeffwallace]

“Causes the airplane to want to turn to the left.” I love how quickly a physics lesson is summarized by endowing the machine with free will.

[@harshalparab95]

Another reason for aircraft yawing to left is spiral effect. Where the airflow or thrust produced by propeller goes clockwise around the air plane's body or fuselage and hits the vertical stabiliser which makes aircraft yaw to the left.. You can read more up on this in principle of flights.. I cleared my technical thanks to you. 👍

[@ErimTuna172]

It took long time for me to understand this subject in order to pass my Principles of Flight exam. I studied long time to understand, just to know this subject in the video. I passed my exams with the help of flightclub. Thank you very much. I got excited when I got notification that flightclub uploaded a new video. I don't need this information now at all but I enjoyed watching it, without hesitating if I am going to be able to pass my next exam. Thanks a lot! I burnt my ATPL books but I will keep following your channel :))

[@flightclubonline]

Thank you so much for taking the time to write these kind words. Much appreciated. All the best.

[@crazypilot4017]

Typically why we use right rudder on take off, until the aircraft gets up to speed. Good stuff. 👍

[@EatPezzzz]

But that's due to propeller slipstream going around the fuselage. I generally fly pusher airplanes and those require no rudder input during climb, descend, or any range of throttle input.

[@SgfGustafsson]

No that's from the spiraling slipstream and torque effect. What is described in the video is P-Factor, which would be most pronounced with a high "deck angle" but level flightpath (like slowflight). In theory a taildragger could experience P-factor during the takeoff roll, but it is not even perceptible at low airspeeds. Before the airspeed would be high enough to make it effective, the tail would be raised already eliminating any P-Factor.

[@cmilburn26]

Ya this is false. That may be true after you rotate and you’re climbing, but on the takeoff roll, we use right rudder to counteract the propwash hitting the vertical stab, as well as the torque from the engine.

[@cmilburn26]

He’s really acting like he’s a pilot by having a pic of him in a plane… except he’s in the wrong seat lol

[@Alelaran_PL]

True. Interesting. I never thought about it. In fan engines it's partly compensated by engine design, but anyway has small impact.

[@TL_RC]

Wonderful explanation! Now it makes sense why my RC models need a fair bit of right thrust built into the firewall.

[@weeliano]

Awesome explanation!!! That is why we always add a small amount of side thrust to counter this effect. All the while I thought its only for countering the torque generated by the spinning propellor.

[@Hallgrenoid]

Fascinating how so many tiny but crucial details like this hide in almost every bit of technology. Humanity has many flaws but damn is it cool how a bunch of self-replicating fermionic matter has managed to bend nature to its will.

[@elliott7268]

I can just hear "more right rudder! Moreeee!" Echoing in my mind

[@cumradej]

The P-factor. One of the causes of the left turning tendency, for those student pilots out there. Flight instructors don’t drill your head with “Right rudder! Right rudder!” for no reason lol

[@tired9398]

And this is called P-factor! Having flashbacks to “more right rudder” loll

[@MattH-wg7ou]

Great explanation and visual of this effect!

[@flightclubonline]

Thank you! Cheers!

[@neilscarborough6876]

Thank you that's such a great video, 👍

[@orion_13]

It makes a huge difference in RC airplanes. The trust-to-weight ratio is higher. Those of us who still scratch build them put down and to the right angles on the firewall. It is a small adjustment that makes a huge difference.

[@SnotrocketLT4]

Yep, that thrust to weight ratio is a lot higher on RC planes and tail draggers are really affected by this left turn tendency on the takeoff roll. Do you think that’s more from torque, or because tail draggers are pitched up a little (like on the vid) while on the ground? I always thought we offset the centerline of the engine to compensate for torque or gyroscopic effect (I’m not sure what the correct term is) of the engine rather than differing levels of thrust from the different sides of the prop. Really interesting though.

[@timothyhackett7372]

Interesting. I was told that the plane yaws left because the prop wash flows around the plane and pushes on the tail fin. , I guess it's a combination of both

[@reb101a]

I learned it’s multiple factors with the primary being gyroscopic procession.

[@marcelbukuru]

These videos are priceless. They got me prepared for my airline interviews 🫡

[@kodybarnette5098]

Depends on the direction of the prop if it spinning clockwise or counter clockwise this can make the direction it wants to turn to be different

[@DenesElkan-zy9xd]

I now understand!! I think in msfs the engine’s rotation make this! But i now know the propeller is! Thank you so much! This is helpful

[@rock3tcatU233]

I had no idea of this effect, I actually learned something new. :D

[@philgiglio7922]

It's even more complicated for rotary wing aircraft. Huey pilot I know said once that there are 3 P factors involved with copters. The advancing blade on a chopper is the reason the aircraft commander sits on the right in a helicopter. Fixed wing aircraft have the command pilot sit on the left...mostly for visibilty in the pattern.

[@BaconMoney237]

In WW2 there were planes that had guns facing the propellers and shoot bullets through the blades could you explain the science behind that

[@edward002gaming]

that's why some propellers are rotated 3 degrees to the right

[@Andrecio64]

That's why contrarotating blades are superior, also twin props.

[@j.vonhogen9650]

So, if you have two of them hanging from the wings, you can prevent the plane from turning to the left by simply letting them spin in different directions?

[@Sunnanandi]

Here's an interesting propeller story: The early Battle of Britain Spitfires lacked a device to provide variable propeller pitch, which pilots felt was seriously hampering dogfight performance. Supermarine rose to the challenge and working round the clock, had a working system ready for retro fitting to Mk.1's within weeks. Even Supermarine's managing director donned his overalls, loaded his Bentley with the new kits and took it on himself to do on site retro-fitting work at front line RAF bases. This was wartime and such a bureaucray busting go for broke attitude was essential for victory. Indeed, it wasn't until years later that Supermarine realized they had forgotten to invoice the RAF for the cost of the variable pitch upgrade kits and retro fitting.

[@gryphon1six801]

Great explanation, thank you!

[@ambiention]

I was taught the airflow corkscrews around the body of the airplane and hits the tail fin on one side causing yaw to change with power settings. Honestly that explanation never really rung true for me, but I guess I sorta just accepted it. The effect is quite noticeable though. You have to add a good bit of rudder when you pile on the throttle during a go around for example

[@user-uh6kq2wh9g]

Love how this is one of the most oversimplified explanation of aircraft propeller

[@Fanxsmite00]

I mean propellers are complicated but a jet engine is much more complicated for me

[@ombralol]

The effect is 90° after of where the propeller produce more foce due to the higher angle of attack. That will not turn right, but in that example want to pitch up. The turning effect is due to engine torque specially in high power manovra like take off.

[@V100-e5q]

Well, what is the airspeed? While on the runway it changes from 0 to 80 knots. So when the plane starts to roll the angle of attack is the same for up- and downstroke. That changes gradually with increasing speed. And with that the plane lifts the tail first before it rotates. Means the airflow before take-off is again in line with the propeller's axle.

[@kevlarkevlarovisc4120]

СПАСИБО, я долго не мог справится с проблемой рысканья у самолёта, благодаря вам я наконец решу эту проблему

[@mattmenna7928]

This is exactly as complex as I thought they were

[@옹알이-o3y]

이러한 이유때문에 항공모함의 관제탑은 항상 오른쪽에 위치해있었고 그 역사가 굳어지면서 지금도 오른쪽에만 있죠

[@mryan18t]

All I heard was “MORE RIGHT RUDDER!!!”

[@evank0385]

confused with a couple questions… if the blade at the top and the blade at the bottom have biggest difference in angle of attack, then wouldn’t the most force be from the bottom and pitch the plane up, not left? Also, wouldn’t this be negligible as the plane is flying where it’s pointing? (Shouldn’t the blue line in the video be parallel with red line for the most part?) Finally, why does a bigger angle of attack generate more thrust? Thanks

[@NoChrReq]

Boats have the same issue and it's called prop walk/paddle effect. You have to know your boat's character and how it affects it in order to manouver in small spaces during leaving or mooring. Unlike aeroplanes, for which its just a small effect, in boats it's one of the fundamentals of navigating and used heavily, either to your advantage or disadvantage.

[@HotelPapa100]

"Aircraft propellers are more complex than you think" For one, they have varying angle of incidence over the radius. I understand it makes it clearer to show the concept you want to demonstrate here to have a flat blade, but damn, that weed cutter looks strange.

[@VoltskkiGaming]

That's why the propeller is always tilted and not straight forward

[@iskanderbaert2173]

Omg this changes so much for me you have no idea

[@JayseB1111]

I may not understand it that well, but I feel this fails to mention the higher thrust on the right side means the center of lift moves right as well - less lift on the outer left and inner right of the wings, & more lift on the inner left and outer right.

[@LTV_inc]

I think it’s more like a gyroscope, the rotating mass wants to spin perpendicular to the axis of rotation. Precession.

[@EatPezzzz]

This isn't the propeller that's complex, it's the various actions and reactions of various stages of flight.

[@rdamoredo]

This is the reason why aircraft carriers have the island on the starboard (right) side of the ship. Having the island on starboard side was key to save pilot lives in WW2 when pilots had abort landing. Today they still have the island on this side just because this historical reasons

[@jay8762]

Wouldnt the force be delayed by 90 degrees due to gyroscopic effects because the blades spin? Which causes it to have a net force going up instead of left?

[@InitialRelic593]

That explain why my instructor always told me to watch out for this

[@nickfromm5315]

This is why jet planes are more popular. And eventually all planes will be jets to eliminate this issue.

[@andreas.9175]

That's crazy. I'm not even a pilot and I notice aircraft drifting to the left when the nose goes up.

[@InsideYourWallsPhD]

This is why most prop planes have adjustable blades

[@erosnemesis]

There are 4 reasons it does this...not just 1. P factor, asymetric thrust, torque, and spiraling slip stream

[@dickdickenson7587]

The turn of the aircraft depends if the propeller is clockwise or anticlocwise also ^^

[@ErimTuna172]

I haven’t seen any anti-clockwise propelling engine in my life. Do you know such aircraft?

[@dickdickenson7587]

@@ErimTuna172 I don't remeber but it usually occour in multiengine aircrafts

[@louisgordon4388]

​@@ErimTuna172 The Rolls Royce Griffon spins counter clockwise, it apparently caused problems for pilots in Griffon engined spitfires as the merlin engines in earlier spitfires spun clockwise so pilots had to learn to apply rudder the opposite way for take-off.

[@danmichaels1562]

​@Erim Tuna a Rotax 2 cycle engine with a gear box.

[@boyakyat8314]

​@@louisgordon4388those engines are clockwise..they installed a reduction gear that end up being a counterclockwise..

[@Turkishgameinvader]

İm studying aircraft engineering and trust me they are even more complicated.

[@flightclubonline]

Indeed

[@Srax499]

That’s why my plane in enlisted never flies straight lol

[@abraham5047]

And that’s talking about fixed pitch props, constant speed props are so much more complicated, I remember learning it for the first time and thinking it would be easy

[@parptot]

super useful for when i need to fly the plane to safety after the terrorist attack!

[@moaayaad10]

Also the gyroscopic effect does a similar job

[@charlesmyers9765]

Maybe I'm missing something but when the aircraft pitches or yaws in any direction isn't the flight path changing also. I mean thats the whole purpose of pitch and yaw.🤷🏻

[@v4riab1lity77]

I speculate this effect is quite nominal in real life examples

[@perialis2970]

But wouldn't this rotation stop once the velocity direction aligns with the propeller?

[@KNIFE-MAN1AC]

Oh so this is the reason my prop plane keep fucking off to the left in sim gotcha

[@DrHundTF2]

So it’s supposed to be bad at takeoff, but ok in flight? I’m asking because I play War Thunder simulator. I know, not the best reference I suppose, but hey, show me another sim game where I can fly the He 51. Anyway, some planes(especially without contra-rotating props) naturally go towards a certain direction, which necessitate trimming to keep straight. Does the prop still give torque in a straight line or is it something else?

[@SetCraft-pm9vk]

This is why single prop planes actually have ther prop offset a little

[@claytonpozzer]

Noo, is about opposite torque, not angle of attack

[@ericcavalheiro]

I barely feel that when i was taking off a cesna, you are most aware whith the side wind

[@bpg5530]

And all this can be avoided by using a 2 engine craft. Really good in terms of stability

[@DimSimSam]

Don’t some single engine planes have an offset propellor to counteract this phenomenon?

[@Rocketeus]

No wonder my bf 109 always hits the control tower in war thunder sim

[@dudenamedchris3325]

And that's why I prefer twin engine rc planes

[@kennedyspace1159]

That is why u always need more right rudder 😂

[@hikton7293]

This is the exact same phenomena that buggles helicopters, only on a smaler scale, so there's no mechanic in the propellar to counter it

[@anshulsingh8326]

How is torque countered? Once I made a helicopter since it was rotating clockwise, my whole motor also started rotation clockwise as it should be. To counter this most helicopters use tail rotors to control that. But what happens in plane ?

[@TCPUDPATM]

Very cool video. Hence the slight rudder? After waving my hands in the air and pretending to be a prop, I don’t think the top and bottom positions are affected the same way, but I’d imagine that advancing and retreating blades of a helicopter are? Thank you!

[@rolandocrisostomo2003]

Does trim fix this issue or is trim just for cruising?

[@sarbjothundal3785]

Bro said “aeroplane” 😭😭😭

[@ajoshdoingthings541]

Hence why we don't just strap boards to motor shafts😂

[@theblock4160]

Assuming that a plane has a propeller on each of their wings, rotating opposite of each other. Would the plane still turn left?

[@Everything-that-flies]

No wonder why in my flight simulators keeping center line is harder on takeoffs

[@dalwinderssi4094]

Question is the trust produced uper and lower propeller,how come it reduces on left side that I could not understand, up and down how they are interchanged with left and right.

[@annonYk]

Yes yes same question here

[@Chris_Mc.]

This is actually what happened at take off when you have an airplane that's tilted before the tail lifts up. It requires a lot of rudder.

[@thenelsonbruhs722]

This is why right turning tendencies are greater during takeoff and climb

[@elgatogaming4198]

So the offset of the propeller is tilted to the right to counteract the yaw?

[@nikfamiliaF]

Турбулентные слои воздуха сталкивающиеся с землей с одной стороны создают избыточное давление выше, чем с противоположной стороны - создают поворачивающий момент. А если самолет в воздухе - то направление потока воздуха по отношению к оси вращения винта как на анимации - будут задирать нос самолета. Разворачивающий момент в воздухе, может возникать только от направления крутящего момента двигателя.

[@Archonch]

Why is gyroscopic precession completely ignored in this?

[@SgfGustafsson]

Because that only comes into play when changing your pitch at high rpm. This video is about a single "left turning tendency", and one of the more difficult ones to understand. There are torque effect and spiraling slipstream also not mentioned making 4 in total.

[@zacharytaylor190]

The propeller is spinning though. As such, wouldnt the point of maximum displacement be 90 degrees ahead of the point of average force application? Gyroscopes would nehave like that.

[@SgfGustafsson]

That only applies to a force that actually displaces the gyroscope. In this case P-Factor is not causing the Propeller to move as the force ends up being transmitted to the driveshaft then the airframe. Precession is fealt when the Propeller is actually physically displaced.