Thanks for this great advice. As a private pilot for over 20 years this is great information. I took 10 years off and have recently returned to flying. Back when I was going for my ppl this was stitched into my subconscious. I need to get back to that. I recently performed a slip to land with a CFI and it felt uncomfortable. If you don’t use it you loose it.
Agreed! Skills like this need to be deeply embedded "muscle memory!" Initially a slip has an uncomfortable "feel" because in cars (most of our transportation) the skidding force is what you feel on every turn. Pilots accustomed to this (we all are) can be dangerous since the favor the feel of a skid. In a slip your butt is falling toward the inside of the turn (initially uncomfortable).
I have always believed this 89.3% of stalls are on takeoff, but hadn't seen the statistics. Thanks very much for that. As a very overloaded Cobra pilot in Vietnam and then Pawnee crop duster here, I also have questioned why ACS wants us to pitch to Vx or Vy as appropriate when they are never appropriate on long runways. Why don't we teach level in low ground effect to Vcc as always appropriate on long runways or normal takeoff? Rod's demonstration is good. Just a little tweak I use is to look between your legs rather than to say look at the nose. The reason most black skid marks are on the left side of the centerline is because pilot is looking over the center of the nose from the left seat position. If the student has the centerline exactly between his/her legs, it is between our (instructor) legs as well. It is optical, we are looking well ahead. Because of the driving, the steering wheel, thing, I also teach/say lead rudder. No, that would not be coordinated. Yes, it helps most students think to be coordinated (use rudder equally as soon as aileron. Stepping on the ball is reaction/correction, and is not coordination. The greatest value, I think, of side slip over crab and yaw only (should be side slip) just before touchdown is that it give the student many seconds of cross control and actually teaches proper dynamic proactive rudder usage (walking the rudder) to bracket/nail the centerline between our legs. Use of skid is uncommon as you say. In crop dusting we do occasionally skid with the nose well down to align with the crop row or GPS light bar coming into the row. We also use the cross controlled skid or rudder turn to move away from an object the wing might hit and then skid back into the proper row. This is to prevent putting a wing down into the crop in a coordinated turn. In any airplane on short final we do not want to turn, coordinated turn. We want to go straight down the centerline extended and keep the centerline bracketed/nailed, exactly between our legs with dynamic proactive rudder only. Proper yaw rather than the very disruptive, here, adverse yaw. I jam my thumb against the stick or bottom of one side of the yoke. When the student tries to use the steering wheel, I yell rudder only...no aileron. If we do not allow the nose, between our legs in side by side, to come off target (except for the small wiggle to bracket and stay ahead of the airplane), we automatically keep the wing level or in a stabilized bank against crosswind. Your cross coordinated at high pitch and high power is also taken care of by dynamic proactive rudder only application. If we are moving our feet we take care of gyroscopic precession when we bring the tail up (TW), and we take care of P factor when the pitch up to bring the mains off. If we rudder only don't let the nose, between our legs, come off exact centerline, the wing stays level. Dynamic proactive rudder is the same a riding a bike or balancing a broom on our hand or defending (feet moving always) in basketball or linebacker in football or awaiting service in tennis. We are better when we move.
Very interesting perspective on the effective use of a skid (cropdusting); I can see the purpose (and effectiveness) if you maintain enough airspeed. I like the term "proactive rudder!" I teach "anticipating" yaw rather than "reacting" (step on the ball BS). Too many CFIs just continuously say "more right rudder" without explaining "why!" If you teach the "why" you learner quickly improves.
@@SAFEPilots Yes, except for landing, we crop dusters value airspeed (which we develop to the max in every low ground effect swath run), over altitude, which we trade (the 200' or so) immediately back for airspeed in the very near 1g turn back into the field at very steep bank angles. All controls mounted on the longitudinal axis can be productively used proactively so long as that use is also dynamic. Yes students learn faster when they are not cautioned about the amount of control movement. If we allow gross they see what they are affecting immediately and thoroughly. Though iterations, they will get more fine movement with experience. We err when we say balance this broom on your hand but don't move your hand very far or much. And yes, the why dynamic proactive is to bracket. We don't know which way the nose is going to go and err in reaction when we do as in precession or P factor. We are better when we move. Athletes are better when they move. Dozer blade operators are better when they move. And we needed sweat the amount so long as the movement left right on rudder pedals or for aft on elevator or in out on throttle is dynamic to bracket the target of that movement. No, I have not mentioned dynamic proactive aileron movement. It is mounted poorly for bracketing. It can be done but adverse yaw makes the eventual bank dynamics not work (say in Dutch rolls) unless we lead rudder for coordination. How can lead rudder be coordinated? Because step on the ball is not. You are doing fine, young instructor. You are seeing the principles which were dropped when we moved from those in "Stick and Rudder" to those implied in the V speeds of ACS. Like you say, "If you teach the why your learner quickly improves."
In addition to actual flying, I recommend using a VR simulator with goggles to help train your brain to learn to fly. Simulators are now inexpensive and very accurate in how they simulate actual flying. The VR goggles make the immersive experience seem like actually being in the cockpit. I've been practicing slips and even spin recovery without any risk of winning the darwin award. Get Microsoft Flight Simulator, start with a Cessna 172, and practice these maneuvers over and over again. It will help cement the automatic response in your brain.
I just invested in a pretty good simulator set-up and I am amazed at the usefulness of practicing on this device (years of stick and rudder flying, but in jets all our training is in simulators). VR adds another more accurate dimension!
I had often asked why are slips safe and skids dangerous? One answer I found was that if a stall occurs, the wing that will drop will be the wing that's away from the ball of the inclinometer. So, in a skid the low wing will drop and you will instantly go into a spin. In a slip, the high wing will drop. This (besides giving the pilot more time to counter react to the motion) improves the aerodynamic situation, meaning because you're slipping the airplane has too much bank for the amount of rudder and the dropping of the wing makes the situation better. I hope I explained this well enough. Comments?
It is true that the stall of the top wing in a slipping spin is more comfortable than the stall of the bottom wing in a skidding stall. This analysis comes up in the much worried about base to final skidding turn stall/spin. Either type spin, even a coordinated rudder/aileron stall, will kill us most likely as we are too low to safely recover from inadvertent stall. It would be equally useful, I think, to teach good wind management like to make base into the crosswind when possible and to start all maneuvering flight turns to target with a bit too much bank so as to likely be able to decrease bank when close to terrain and obstacles around the landing site. High altitude orientation emphasizes stall/spin recovery techniques. Low altitude orientation doesn't even consider stalls, as they are fatal, but emphasizes wind management and energy management like always releasing back pressure on the elevator in turns. This allows the design safety feature of dynamic neutral stability, Wolfgang's "what does the airplane want to do" and "the law of the roller coaster" to function and to save lives. Yes, good explanation.
Yes you have that right. Another way to say what you described is the major aerodynamic forces in a skid are both acting in a downward direction; yaw and roll are both acting toward the low wing! In a slip, roll wants to go downward and yaw- the rudder- is opposing it acting out of the turn. The yaw and roll in opposition create stability. As mentioned in the presentation, if you stall in a full power-off slip at altitude (with a competent CFI please) the plane stays level and the nose does not even drop!! This demonstrates the inherent stability of a slip!
A slip transfers some of the lifting chore to the side of the fuselage, which is a very inefficient wing - hence the success of a slip in losing altitude without gaining speed. The aerodynamically identical skid doesn't offload any of the lift from the wings so has a higher stall speed. To prove it, at altitude, point your taildragger up into nearly a power off stall and then to a full control slip (to the left is easier), full left stick full right rudder, keep the nose up. It doesn't stall because the wings aren't producing much lift. You can continue this almost all the way into the landing once you get the hang of it. It's an incredibly steep descent. The airspeed will usually read less than zero but jump to 60 when you roll out at the end. If you do a wheel landing out of a steep slip, you can hit the spot aimed for without a few feet every time.
And this is a *very advanced* maneuver for those reading (do not try this without some professional help and practice)...as this commenter mentioned, the rate of descent in this configuration is massive (reminds me of an autorotation in a helicopter). Energy management and timing of the flare are critical🤣.
That is a good binary formula. If you want to create a slip I usually advise to "step on the high wing" with the rudder (this opposes the turn and creates the slip; stable!)
In a forward slip with a moderate right to left Crosswind, your nose is pointed to the right, is it imperative that you’re right wing be the low wing or can it be the high wing?
If you are slipping into a crosswind, the nose of your aircraft is *away* from the wind (ailerons into the wind and rudder to the opposite -high wing- side): right to left crosswind would have nose to the left...plane moving to the right.
My Decathlon, like the J-3 at the beginning of this video, doesn’t have flaps. Every landing is a no-flap landing. Forward slips are pretty much a regular part of landing. Not every landing has to look like an airshow, but it does look cool!
Yes, no flaps in many tailwheels so the slip has always been the traditional tool to add drag and descend faster (flaps available in modern "nosedraggers)🤣
We need to learn how all the flight controls work. Move the rudder only. Learn what happens. There is more good than bad. Move the aileron only. Learn what happens. There is useful bank but the nose going different than we expect is disruptive, especially on short final where we don't want to turn anyway and should never crank the steering wheel. Correct yaw, rudder only yaw, continuous dynamic proactive rudder yaw, is how we most skillfully direct a course to a target like the centerline.
Yes, the "acro-guys" obviously know how to use the rudder! And I learned (below) that cropdusters also occasionally skid to line-up when very low (those led line-up devices) - but skidding is only very rare and carefully deployed.
Outstanding! Thank you so much for such valuable lecture!
Thanks🙏
Forgot to say,. This was an excellent presentation! I have already backed up and replayed many of your statements over again. Thank you.
Wow, thank you!🙏
Thanks for this great advice. As a private pilot for over 20 years this is great information. I took 10 years off and have recently returned to flying. Back when I was going for my ppl this was stitched into my subconscious. I need to get back to that. I recently performed a slip to land with a CFI and it felt uncomfortable. If you don’t use it you loose it.
Agreed! Skills like this need to be deeply embedded "muscle memory!" Initially a slip has an uncomfortable "feel" because in cars (most of our transportation) the skidding force is what you feel on every turn. Pilots accustomed to this (we all are) can be dangerous since the favor the feel of a skid. In a slip your butt is falling toward the inside of the turn (initially uncomfortable).
Great presentation, thank you! As a glider CFIG I teach slips to all of my students once they are sufficiently advanced.
Yes, a glider CFI myself; an essential skill.
I have always believed this 89.3% of stalls are on takeoff, but hadn't seen the statistics. Thanks very much for that. As a very overloaded Cobra pilot in Vietnam and then Pawnee crop duster here, I also have questioned why ACS wants us to pitch to Vx or Vy as appropriate when they are never appropriate on long runways. Why don't we teach level in low ground effect to Vcc as always appropriate on long runways or normal takeoff?
Rod's demonstration is good. Just a little tweak I use is to look between your legs rather than to say look at the nose. The reason most black skid marks are on the left side of the centerline is because pilot is looking over the center of the nose from the left seat position. If the student has the centerline exactly between his/her legs, it is between our (instructor) legs as well. It is optical, we are looking well ahead. Because of the driving, the steering wheel, thing, I also teach/say lead rudder. No, that would not be coordinated. Yes, it helps most students think to be coordinated (use rudder equally as soon as aileron. Stepping on the ball is reaction/correction, and is not coordination.
The greatest value, I think, of side slip over crab and yaw only (should be side slip) just before touchdown is that it give the student many seconds of cross control and actually teaches proper dynamic proactive rudder usage (walking the rudder) to bracket/nail the centerline between our legs.
Use of skid is uncommon as you say. In crop dusting we do occasionally skid with the nose well down to align with the crop row or GPS light bar coming into the row. We also use the cross controlled skid or rudder turn to move away from an object the wing might hit and then skid back into the proper row. This is to prevent putting a wing down into the crop in a coordinated turn. In any airplane on short final we do not want to turn, coordinated turn. We want to go straight down the centerline extended and keep the centerline bracketed/nailed, exactly between our legs with dynamic proactive rudder only. Proper yaw rather than the very disruptive, here, adverse yaw. I jam my thumb against the stick or bottom of one side of the yoke. When the student tries to use the steering wheel, I yell rudder only...no aileron. If we do not allow the nose, between our legs in side by side, to come off target (except for the small wiggle to bracket and stay ahead of the airplane), we automatically keep the wing level or in a stabilized bank against crosswind.
Your cross coordinated at high pitch and high power is also taken care of by dynamic proactive rudder only application. If we are moving our feet we take care of gyroscopic precession when we bring the tail up (TW), and we take care of P factor when the pitch up to bring the mains off. If we rudder only don't let the nose, between our legs, come off exact centerline, the wing stays level. Dynamic proactive rudder is the same a riding a bike or balancing a broom on our hand or defending (feet moving always) in basketball or linebacker in football or awaiting service in tennis. We are better when we move.
Very interesting perspective on the effective use of a skid (cropdusting); I can see the purpose (and effectiveness) if you maintain enough airspeed. I like the term "proactive rudder!" I teach "anticipating" yaw rather than "reacting" (step on the ball BS). Too many CFIs just continuously say "more right rudder" without explaining "why!" If you teach the "why" you learner quickly improves.
@@SAFEPilots Yes, except for landing, we crop dusters value airspeed (which we develop to the max in every low ground effect swath run), over altitude, which we trade (the 200' or so) immediately back for airspeed in the very near 1g turn back into the field at very steep bank angles. All controls mounted on the longitudinal axis can be productively used proactively so long as that use is also dynamic. Yes students learn faster when they are not cautioned about the amount of control movement. If we allow gross they see what they are affecting immediately and thoroughly. Though iterations, they will get more fine movement with experience. We err when we say balance this broom on your hand but don't move your hand very far or much. And yes, the why dynamic proactive is to bracket. We don't know which way the nose is going to go and err in reaction when we do as in precession or P factor. We are better when we move. Athletes are better when they move. Dozer blade operators are better when they move. And we needed sweat the amount so long as the movement left right on rudder pedals or for aft on elevator or in out on throttle is dynamic to bracket the target of that movement. No, I have not mentioned dynamic proactive aileron movement. It is mounted poorly for bracketing. It can be done but adverse yaw makes the eventual bank dynamics not work (say in Dutch rolls) unless we lead rudder for coordination. How can lead rudder be coordinated? Because step on the ball is not.
You are doing fine, young instructor. You are seeing the principles which were dropped when we moved from those in "Stick and Rudder" to those implied in the V speeds of ACS. Like you say, "If you teach the why your learner quickly improves."
In addition to actual flying, I recommend using a VR simulator with goggles to help train your brain to learn to fly. Simulators are now inexpensive and very accurate in how they simulate actual flying. The VR goggles make the immersive experience seem like actually being in the cockpit. I've been practicing slips and even spin recovery without any risk of winning the darwin award. Get Microsoft Flight Simulator, start with a Cessna 172, and practice these maneuvers over and over again. It will help cement the automatic response in your brain.
Hey I have a setup like you - I find my Just flight 172 is terribly inaccurate to the real 172 I practice in. But I 100% agree with your comments :)
What 172 do you use
I just invested in a pretty good simulator set-up and I am amazed at the usefulness of practicing on this device (years of stick and rudder flying, but in jets all our training is in simulators). VR adds another more accurate dimension!
I had often asked why are slips safe and skids dangerous? One answer I found was that if a stall occurs, the wing that will drop will be the wing that's away from the ball of the inclinometer. So, in a skid the low wing will drop and you will instantly go into a spin. In a slip, the high wing will drop. This (besides giving the pilot more time to counter react to the motion) improves the aerodynamic situation, meaning because you're slipping the airplane has too much bank for the amount of rudder and the dropping of the wing makes the situation better. I hope I explained this well enough. Comments?
It is true that the stall of the top wing in a slipping spin is more comfortable than the stall of the bottom wing in a skidding stall. This analysis comes up in the much worried about base to final skidding turn stall/spin. Either type spin, even a coordinated rudder/aileron stall, will kill us most likely as we are too low to safely recover from inadvertent stall. It would be equally useful, I think, to teach good wind management like to make base into the crosswind when possible and to start all maneuvering flight turns to target with a bit too much bank so as to likely be able to decrease bank when close to terrain and obstacles around the landing site.
High altitude orientation emphasizes stall/spin recovery techniques. Low altitude orientation doesn't even consider stalls, as they are fatal, but emphasizes wind management and energy management like always releasing back pressure on the elevator in turns. This allows the design safety feature of dynamic neutral stability, Wolfgang's "what does the airplane want to do" and "the law of the roller coaster" to function and to save lives.
Yes, good explanation.
Yes you have that right. Another way to say what you described is the major aerodynamic forces in a skid are both acting in a downward direction; yaw and roll are both acting toward the low wing! In a slip, roll wants to go downward and yaw- the rudder- is opposing it acting out of the turn. The yaw and roll in opposition create stability. As mentioned in the presentation, if you stall in a full power-off slip at altitude (with a competent CFI please) the plane stays level and the nose does not even drop!! This demonstrates the inherent stability of a slip!
@@SAFEPilots Thank you. I really like the way you put that!
Fantastic presentation
Thank you, please subscribe, we have many more on the way.🙏
Excellent video
Thank you!
A slip transfers some of the lifting chore to the side of the fuselage, which is a very inefficient wing - hence the success of a slip in losing altitude without gaining speed. The aerodynamically identical skid doesn't offload any of the lift from the wings so has a higher stall speed. To prove it, at altitude, point your taildragger up into nearly a power off stall and then to a full control slip (to the left is easier), full left stick full right rudder, keep the nose up. It doesn't stall because the wings aren't producing much lift. You can continue this almost all the way into the landing once you get the hang of it. It's an incredibly steep descent. The airspeed will usually read less than zero but jump to 60 when you roll out at the end.
If you do a wheel landing out of a steep slip, you can hit the spot aimed for without a few feet every time.
And this is a *very advanced* maneuver for those reading (do not try this without some professional help and practice)...as this commenter mentioned, the rate of descent in this configuration is massive (reminds me of an autorotation in a helicopter). Energy management and timing of the flare are critical🤣.
If the ball is low you’re good to go, if the ball is high you’re gonna die.
That is a good binary formula. If you want to create a slip I usually advise to "step on the high wing" with the rudder (this opposes the turn and creates the slip; stable!)
Excellent!
Many thanks!
Great vid
Much appreciated; tune in for more!
@SAFEPilots
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In a forward slip with a moderate right to left Crosswind, your nose is pointed to the right, is it imperative that you’re right wing be the low wing or can it be the high wing?
If you are slipping into a crosswind, the nose of your aircraft is *away* from the wind (ailerons into the wind and rudder to the opposite -high wing- side): right to left crosswind would have nose to the left...plane moving to the right.
Why do tailwheels do it, just to look and feel cool? Why can’t they land like everybody else?
My Decathlon, like the J-3 at the beginning of this video, doesn’t have flaps. Every landing is a no-flap landing. Forward slips are pretty much a regular part of landing. Not every landing has to look like an airshow, but it does look cool!
And its a lot of fun! Slips are a great tool in emergencies; stay high and slip off the altitude when the field is "made!"
Yes, no flaps in many tailwheels so the slip has always been the traditional tool to add drag and descend faster (flaps available in modern "nosedraggers)🤣
THERE IS a place for skid in aviation: if you are an acrobatic pilot during initialization for SPIN.
We need to learn how all the flight controls work. Move the rudder only. Learn what happens. There is more good than bad. Move the aileron only. Learn what happens. There is useful bank but the nose going different than we expect is disruptive, especially on short final where we don't want to turn anyway and should never crank the steering wheel. Correct yaw, rudder only yaw, continuous dynamic proactive rudder yaw, is how we most skillfully direct a course to a target like the centerline.
Yes, the "acro-guys" obviously know how to use the rudder! And I learned (below) that cropdusters also occasionally skid to line-up when very low (those led line-up devices) - but skidding is only very rare and carefully deployed.