Slips
1. What is a slip? An airplane is said to “slip” in a turn when the angle of bank is excessive for the rate of turn and rudder input. Basically, the plane slides sideways toward the low wing and the inside of the turn. Pilots devote much effort to the art of making “coordinated turns” in which the aileron and rudder input is balanced and the plane neither slips nor skids. However, a plane may be placed in a slip on purpose in order to lose altitude quickly without picking up a lot of airspeed in the process. This is a trick often used by experienced pilots on final approach to a landing. It requires a fine touch to perform this maneuver effectively, smoothly, and safely, and a slip to a spot landing, expertly done, commands the respect of other pilots. The plane is put into a slip by applying rudder in one direction while banking in the opposite direction. That is, the controls are crossed. For example, right rudder with left stick (or the other way around). This causes the nose of the plane to veer to the right at the same time the left aileron produces a bank to the left. The plane then travels through the air sort of sideways at an unusual angle that novice pilots sometimes find a bit disconcerting. Additional drag is produced because the relative wind strikes the side of the fuselage, and it is this drag that prevents the buildup of airspeed when a slip is used to lose altitude quickly. Sideslip vs. Forward Slip Whether a plane will turn while in a slip depends upon the relative amounts of aileron and rudder input. A slip done in such a manner that no turn is produced is a “forward slip.” The tendency of the rudder to make the plane turn in one direction is offset by the effect of the ailerons to make it turn in the other. This is the type of slip normally used by pilots on final approach when they are lined up perfectly with the runway. A “sideslip,” on the other hand, causes the plane to slide sideways without having the nose of the plane rotate at all. For example, suppose a plane on short final is a few feet to the right of the center line of the runway. All that is needed is to move a few feet to the left. A gentle slip will produce this movement with fewer control inputs than if coordinated turns are used, with the added benefit that the nose of the plane is maintained straight ahead all the while. (Important part of landing: keep the nose of the plane pointed straight down the runway.) Sideslips are also used to counteract wind drift during a crosswind landing. Slipping while in a Turn Suppose a pilot on base leg is about to turn onto final and suddenly realizes that he or she is a bit high and a bit fast. The slip can be initiated while in the turn in order to lose the excess altitude and slow down as soon as possible. Strictly speaking, this is neither a forward slip nor a sideslip; it's simply a slip in a turn. Three Different Kinds of Slips? No, not really. Basically, a slip is a slip, is a slip. A pilot does not have to make a conscious decision as to what type of slip to perform in a given situation. You just do the slip within the context of the maneuver you are already performing. It's much easier than you think. 2. Hazards associated with a Slip Slips are dangerous. A slip that goes bad can easily end up in a cross-control stall which can easily end up in a sharp roll to nearly inverted, or a spin. (See the article, Stalls 201 in this same section.) Factors that make a slip dangerous include: A. Airflow over the high wing is disturbed by the wake of the fuselage. The fuselage is not streamlined at all for air flowing over and around it at an angle. This produces a region of turbulence in the area of the high wing so that it is subject to the unpredictable peculiarities of turbulent flow. B. The stall speed will be HIGHER in a slip, and if a stall occurs, it is likely to be ugly. The relative wind is directed across the wings at an angle instead of straight from front to back. This alters the effective curvature of the wing's airfoil and results is less effective production of lift. Because the high wing flies in the turbulence produced by the fuselage, it is likely to stall first while the low wing is still producing considerable lift. This gives a strong tendency for the plane to roll toward the high wing. (However, if the plane is turning toward the low wing, the low wing may stall first.) C. The airspeed indicator is subject to inaccuracies in a slip. Because the entire plane is canted at an angle to the relative wind, the air will not strike the pitot tube exactly head on. This will produce less pressure in the pitot system and will tend to make the ASI read low. However, another effect that is perhaps more important is the effect of the slip on the pressure in the static air system. The ASI works by comparing pitot and static pressure so that if the slip produces a change in the static pressure, the ASI indication will be affected. Planes having the static line vented into the cockpit are especially vulnerable to this effect. In particular, if the slip produces a lower static pressure, the ASI will read high. This might cause you to stumble into an unexpected stall. If the static port is located on the side of the fuselage, it is possible for the ASI to behave differently in a slip to the left as opposed to a slip to the right. D. The recovery from a slip can be “wobbly” and ungraceful. Simply neutralizing the controls will cause most planes to recover from a slip, but this is not guaranteed for each and every plane. Some may require a bit of control input in the opposite direction. In either case, the recovery should be executed smoothly and without letting the nose of the plane swing to the opposite side. A lack of smoothness could possibly initiate an oscillation about the yaw axis, and if this is then aggravated by overcontrolling, the ride could be a bit unpleasant and unpredictable. For this reason, the recovery should be done while there is sufficient altitude remaining to deal with a wobbly recovery. Expert pilots can slip gracefully to within a few feet of the runway, straightening out only at the last moment. At the same time, an inexperienced pilot can wreck in short order by slipping to too low an altitude and then being ungraceful or unsmooth in the recovery. 3. How to do slips Power at idle Because the intent of a slip is to lose altitude quickly, it stands to reason that the engine should be pulled back to idle. Otherwise, the engine power would serve to offset the effect of the slip.Cross the controls Apply the desired amount of rudder in one direction while moving the stick in the opposite direction. The extent of the slip is determined by the rudder input. You can slip a little or a lot, depending upon the amount of rudder applied. The rudder is deflected all the way to the stops in a “full slip.” Aileron input determines the direction of flight in a slip. A certain amount of aileron input relative to the opposite rudder will produce a flight path straight ahead, i.e., a forward slip. More aileron will produce a turn toward the low wing. However, an attempt to turn toward the high wing by reducing the angle of bank is usually not very effective. If a significant turn is needed in the direction of the high wing, it is more expedient to quickly reverse the direction of the slip and then turn toward the new “low wing.” In a sideslip, rudder input is applied as needed to keep the nose of the plane pointed straight ahead after aileron input produces a bank. In this case, the extent of the slip is determined primarily by the angle of bank. A “slip in a turn” is done simply by applying less than the ideal amount of rudder for the turn. The least of these is simply an uncoordinated turn due to too little rudder input. In the extreme, considerable rudder may be applied in the direction opposite the turn. The angle of bank and rudder together determine the rate of turn. The rate can be increased by increasing the bank angle or by reducing the opposite rudder. However, as you reduce opposite rudder input to quicken the turn, the resulting amount of slip will decrease. A slip in a turn is best kept on the mild side. The tendency is to lose altitude more quickly in a turn anyway. If you add a bit of a slip, the rate of decent will be quite pronounced. Also, keep in mind that in a turn the low wing is traveling through the air just a mite more slowly than the high wing and will tend to stall first if it comes to that. Let your experience, ability, and common sense guide you in this regard. You can wreck hard very easily if you get it all tangled up! Apply forward stick pressure. The excess drag produced by the wind striking the fuselage will tend to slow the plane in a slip. Therefore, forward stick pressure will be required to maintain the airspeed. In fact, the forward pressure is an integral part of doing a slip. That is, rudder, opposite aileron, and forward pressure all go together. Now, exactly how much forward pressure should be applied is a matter that has received considerable discussion and debate. The slip will produce a greater rate of descent with less forward pressure and a nose-high attitude, but this will produce a lower airspeed and put you closer to the edge of a stall. The conservative approach is to use a lot of forward pressure. However, this can cause the airspeed to increase, even in the slip, so that you wind up with excess airspeed after recovering from the slip. Only experience and practice in a particular plane can tell you exactly how much forward pressure you should use. And, don't forget that the airspeed indicator may be slightly out of whack during the slip and the stall speed is almost certain to be higher. And if you stall, it will not be pretty. And it goes without saying that slips should be practiced at altitude before they are attempted during an approach to a landing. Also, the comfort level during the practice will be slightly higher and the cockpit somewhat cooler if a qualified instructor is on board as well. 4. Alternatives to Slips Other possibilities are available for losing altitude on final approach. These include (1) a high-speed dive, (2) a very low airspeed, and (3) S-turns. Each of these is appropriate only while “far out” on final approach. Whether any one is as effective as a slip is subject to debate, but the advantage is that the controls are not crossed and the plane remains aligned with its direction of travel. By and large, it's a matter of preference. High-speed dive This technique consists of diving the plane steeply at a point short of the runway and allowing the airspeed to increase dramatically. The drag increases as the square of the airspeed so that considerable energy is expended due to the additional drag. Also, significant G loading will occur during roundout at the bottom of the dive and this will further tend to slow the plane. The disadvantage, of course, is that at the bottom of the dive, the plane will be traveling at high speed. This is the reason for aiming at a point short of the intended touchdown point. This will work only for planes that are “draggy” or for planes that have flaps that contribute drag when the flaps are deployed. With slick, streamlined, low-drag planes, the horizontal distance required to get down by diving sharply from a given altitude may very well turn out to be greater than for a normal approach. The speed in the dive must be significantly higher than the normal approach speed. For example, in a Cessna 172 with full flaps, the normal approach speed may be 60 - 65 mph. To use a high speed dive to lose altitude, a 172 needs to be pushed over to give an airspeed of 100 mph, the maximum allowed with flaps deployed. In this situation, the nose will be pointed down at a steep angle and you will be hanging on the belts. And, the ground comes up quickly. For the most part, this is an all-or-nothing situation. If you dive just a little and let the airspeed increase only 10 mph or so, you are likely to wind up touching down even farther down the runway, if you manage to land at all. This is especially true if landing into a headwind. Nothing is more disconcerting than to dive down to the numbers and then float halfway down the field before touching down. Very low airspeed Conventional piloting wisdom holds that in order to get down in the minimum horizontal distance, you should raise the nose. That is, slow the plane down to just above the stall speed where the drag will be increased due to the increased angle of attack. This is especially effective if landing into a significant headwind. By slowing the plane and making a slower approach, you give the wind more time to blow you backwards, relatively speaking, away from the runway. Conversely, if you want to extend your glide, you should lower the nose and make the approach at a higher speed. This will minimize the time you are exposed to the wind. However, in this case, do not lower the nose so much that the speed becomes excessive or you will wind up losing extra altitude because of the high-speed dive phenomenon described above. There are two pitfalls associated with making an approach at an airspeed just above the stall. First, and obviously, you don't want to get the speed so low that the plane stalls or even develops a very high sink rate without stalling. (See the description of an oscillating stall in Stalls 201, in this same section.) Second, when you arrive at the touchdown point, you must be sure your airspeed is high enough to enable you to flare. It is easy to pancake in to a hard landing if the sink rate is excessive and the airspeed low. Nothing is more disturbing than to approach the touchdown point, pull back on the stick to flare, and have nothing happen. Ugh! It will scare the daylights out of you even if you don't wreck the plane! S-Turns Suppose a pilot on base leg recognizes that he or she is too high before turning on final. A lot of the extra altitude can be gotten rid of simply by incorporating extra turns into the remaining part of the pattern. A plane loses altitude more readily in a gliding turn than in a glide straight ahead. First, the plane should be slowed to an airspeed just comfortably above the stall. An option, while still on base leg, is to turn outward from the runway by 30 degrees or so. This will lengthen the final a short amount, but more importantly, it gets the plane into the turning mode. Additionally, it increases the amount of turn required to turn onto final. This idea can be extended by flying on past the runway center line without turning onto final. You will then need additional turning to come back to center line, and all the turning contributes to loss of altitude with minimal advancement toward the runway. Once on final, you can do S-turns so that the turning action is continued even as you are on the final approach. However, two points are noteworthy. First, the turns need to be fairly steep in order to be effective, and they need to result in the nose achieving a maximum departure from the runway heading of about 45 degrees. Here, a steep turn implies an angle of bank of at least 30 degrees, preferably closer to 40. The second point is this: What must you watch very carefully while doing a steep turn? Airspeed, of course. Keep the airspeed well above the power-off stall speed, and remember that the stall speed will be slightly greater in a steep turn. The last thing you want to do is stall ... that would bring you down too quickly. Pronounced, steep, S-turns on final approach may not be looked upon with favor by those on the ground who may be in a position of authority. After all, a rule of thumb says that turns in the pattern should not include bank angles greater than 30 degrees. The final approach phase of a landing is supposed to be fairly uneventful, even boring. And there is the notion that you should not do steep turns at low altitude. Now having said all this, at length, ... a good pilot knows his plane, can slip expertly with confidence, can fly it slowly, and can do S-turns with the best of them. However, a GREAT pilot will plan ahead, watch the airspeed and altitude as he or she advances around the pattern, and then WILL NOT end up too high or fast on base or final. The great pilot will not need the fancy whifferdills just to get down to the runway. 5. Posts Relating to Slips from the FlyChallenger List The following posts give a sense of how slips are regarded in the real world of flying airplanes, Challengers in particular, and pose some typical questions about slips. So, in their own words, ... Paul V. July 3, 2003 Msg # 46410 Who will give me the slip ? I need to know how and when to use the slip. I have been flying solo for 50 hours now, and I am ready to learn. I have tried to cross up the controls, and each time I try it I seem to get different results. Can someone put a perspective on this for me? Thanks, Paul V. Alvin Melton July 3, 2003 Msg # 46417 Re: Who will give me the slip? Being the adventurist that I am I started slipping right away... a lot depends on the air outside the plane, and how you enter the slip... Keep practicing...each plane is different... and you will eventually get a feel for how and why it reacts like it does. I was freaked out by the weird angle in which you head for the earth...but I got used to it. Practice practice practice... Alv Jean-Paul Roy July 3, 2003 Msg #46418 Re: Who will give me the slip? I freaked out too when I tried it first time with the Challenger as I was used to doing it a lot in an Aeronca Champion. I kept the nose nearly horizontal and all in a sudden, my ASI showed almost ZERO. Like you said practice practice practice is the answer. J.P. Daniel Wroe July 3, 2003 Msg # 46419 Re: Who will give me the slip? Yeah, can't trust the ASI at all, during a slip. Both the cabin static and the geometry of the pitot change, throwing everything off. The good news is that the plane telegraphs it's intention to stall very well, so its relatively easy to stay out of trouble. dabzinc1@a... July 3, 2003 Msg # 46428 Re: Who will give me the slip? What you are asking about is a forward slip I believe. This happens when you intentionally give partial or full rudder and opposite ailerons. In other words, Deflect the rudder to the right and move your stick to the left. This makes the plane yaw to the right but it will stay level because of the opposite ailerons. A forward slip is used primarily to get rid of extra altitude on final approach. A very useful tool for short fields when going long is not an option. Beware! Performing a forward slip will increase your risk of a stall/spin. I suggest you practice this with a lot of altitude on a practice target. This way if you stall you will have time to recover . Don't forget to straighten the plane out and level the wings before touching down or you will find out what a ground loop is real fast. Good luck! Oh yeah! do this with an instructor. - Bob Jim Hayward Jul 3, 2003 Msg # 46430 Re: Who will give me the slip ? Paul wrote: “ I need to know how and when to use the slip. I have been flying solo for 50 hours now, and I am ready to learn.” Okay, Paul, below are some posts I found in my stuff from some time ago. They were posted by our illustrious Don Zank who is one of the guru's on our list. I don't remember who "Dave" was that posted the last one. Jim H. Don Zank: To do a slip in your Challenger effectively you should have the nose UP. The higher you raise the nose the more dramatic the slip. You can see yours truly demonstrating a normal Challenger slip near the beginning of the challenger video. A slip with lots of airspeed is not very effective at all because you then have too much speed to get rid of before touchdown. Timed perfectly, a big slip to landing is a thing of beauty. Timed wrong, of course, it can result in bent gear legs. :>) :>) :>) DZ Don Zank: Ok guys, someone needs to clear up this conversation about slips. I was taught to slip with the noise down on the CII and passed my check ride with a down attitude for an aggressive slip, is this wrong? When you straighten out from the slip, if your speed is 35 or more, you just will not land as short (the whole idea of the slip). Most guys that I see slip in kick it straight and then still go down the runway a billion miles. Your wheels should touch down very shortly after you get straight. It does require lots of practice so that you don't ding a gear, so practice with some altitude first. When on final, I get the nose up, at idle power, and get right close to the stall. I then lower a wing and get the rudder all the way to the stop. This gives you a hellacious bank angle and will require lots of pull to keep the nose up (with relation to the airflow of course). All controls should be as near as possible to their full deflection. Keep your head and make the corrections necessary to keep it lined up. It is VERY easy to get out of whack so pay attention and do it at altitude first. By the way, it is very difficult or impossible to get really radical with it if the front seat pilot is over about 220 pounds. :>) :>) Another reason to tell him to diet a bit. :>) :>) DZ Dave Actually, both techniques are correct. If you find you are too high, going to overshoot the runway and have to lose some altitude quickly, then you need to slip with the nose down. This creates a lot of drag and kills altitude while still having enough speed for a nice flare. If you are trying to get in to a very short strip you may have to slip with the nose level or slightly up to keep your airspeed down so you don't flare off the end of the runway. Be careful with slow speed slips so as not to stall out. Dave Jay Dewberry Sept. 9, 2002 Msg # 34960 Slips What is the best speed to slip? What is the max speed to slip a Challenger? I think I remember Larry D stating that he dove at idle to get down quickly. Which is the quickest way down, and at what speed. Jay J. D. Stewart Sept 9, 2002 Msg # 34962 Re Slips I usually slip around 55mph, but the airspeed isn't going to be accurate going sideways. I have slipped 1800'/minute, going darn near vertical. Full deflection of rudder, and enough aileron to keep it going the way I want it. I doubt you want to be diving that fast. J.D. Rick Marshall Sep 9, 2002 Msg # 34963 Re: Slips I was instructed to slip a plane at your landing approach speed, which I do at 5 to 10 mph above stall. Rick Marshall, N9103L Alvin Melton Sept 9 2002 Msg # 34964 Re: Slips I'll go into the slip about 60MPH and depending on how I feel...slow it down or speed it up...going in at 60 it usually registers about 50 on the ASI... I love dropping fast, I don't have a variometer to tell how fast I'm dropping but on many occasion hit full lock with the rudder/aileron...fun!! Practice with it and see how you like it.... Alv Doc Green Sept 10, 2002 Msg # 34267 Stall in a Slip ?? Here's a question: What happens in a stall when the controls are severely crossed? And does the plane stall at the same speed in a slip as when flying straight ahead? Might it not stall at a higher speed due to the disturbed airflow around the plane? Has anyone taken a Challenger up to altitude, crossed the controls, and let it stall? dirtdobber47 Sep 10, 2002 Msg # 34968 Re: Stall in a Slip ?? NOT A GOOD IDEA! When you cross control you should always have your nose down to prevent a flat spin. Wayne drifter 582 Don Zank Sept 10, 2002 Msg # 34970 Re: Stall in a Slip You have never seen me slip, I betcha. :) A nose down slip in a C will make you too fast. A nose up slip will bring you down STEEP!! Yes indeed you gotta go practice at altitude!! I hesitate to even say that nose up thing, but there you are. Now someone will break their plane and blame it on me. PLEASE DON"T do what I do. I do my slip in a nose high full stall!!! That's why I come down sooooo steep. :) :) Please don't do that, but stop by and see it if you get a chance. :) :) DZ From: szigat99 Sep 10, 2002 Msg # 34971 Re: Stall in a Slip ?? I've been playing around with slips too. Seems like an important maneuver to do well. I was in a two place trainer once and had an engine out. My instructor slipped the plane into a field nearly directly below. Then told me never to slip a plane without forward pressure on the stick. My question to Don is, What happens when a slip goes bad? Is the wing going to drop so fast I can't recover with forward motion on the stick? I've been doing little baby slips nearly all the way down to just before I round out. (no name given) Mark Huntley Sep 10, 2002 Msg # 34972 Re: Stall in a Slip ?? A cross controlled stall usually occurs while turning base leg to final approach. If your intention is to slip, do so after the turn to final to avoid the cross controlled stall. Now to answer the other questions: The stall speed should remain the same as its a function of the relative angle of attack of the wing. The only thing that will change this is load factor (turns) and the use of flaps (aerodynamic change). I have not crossed controlled a Challenger to a stall, but I have taught this to my students in aerobatic general aviation airplanes (I was an aerobatic instructor in a T-34A). A cross control stall is violent. The leading wing will stall first, and the airplane will stall around it. Furthermore, the recovery altitude for the T-34 in a cross controlled stall was 800 ft, whereas the recovery altitude for straight ahead stalls was only 100 to 200 feet. Bottom line is that cross controlled stalls are UNRECOVERABLE at low altitude prior to impact if done on final approach. My advice is to practice normal stalls at sufficient altitude for recovery. Learn to recognize stalls, practice good recovery techniques, and then avoid them. I would also support having a BRS system as well. Daniel Wroe Sep 10, 2002 Msg 34975 Re: Stall in a Slip ?? Doc Green wrote: “What happens if you happen to stall while in a slip, say, at an altitude of 100 feet or so above the ground while on final approach?” Don't. That having been said, and at the risk of encouraging someone to do something they're not ready for... In concept, a cross controlled stall is the textbook entry for a spin. Be it the base to final turn or whatever, a -lot- has been written about the dangers of cross controlled stalls, particularly at altitudes too low for recovery. In practice, the Challenger is really docile in a stall. It seems to me like it takes a lot of un-coordination to get an appreciable wing drop. Stall recovery with the correct technique is practically instantaneous. My theory is that the low speed airfoil and low dihedral used on the Challenger means that there is not as critical a difference in the angle of attack of the two wings when it is cross-crontolled. This is not to say you can't force it or ham-hand it into a spin, but it does give you plenty is time to fix the situation. Doc Green: “And does the plane stall at the same speed in a slip as when flying straight ahead? Might it not stall at a higher speed due to the disturbed airflow around the plane? How can you be sure?” More a function of the relative angle of attack of the forward wing, and also to a very small extent the change in the effective airfoil due the air not traveling directly chord-wise over the wing. As far as numbers, I have no idea. Every CII I've flown so far has the static port vented right behind the panel, so a slip raises hell with the ASI as all that wind blows through the cockpit. I've seen everything from past Vne to negative numbers. You'd better expect to know how to fly the slip by feel, which means apprenticing with someone who already knows. BTW, in playing with my GPS, this static method appears to make the ASI read about 5 mph high in cruise, with the doors off. Doc Green: “Has anyone taken a Challenger up to altitude, crossed the controls, and let it stall?” All the time, mostly slow entry. I've probably only fast entried a couple of times, and then it can get a good wing drop. With experience, you can safely play around the edges of the stall, even that nether-region where the buffet is pronounced, but the nose refuses to drop. If you really want to know, find a good instructor with a plane more likely to bite you without much growling. I think a tightly rigged Citabria would give you a good appreciation. I did my BFR in one after about 400 hours in the Colt and it was humbling. Fly safe. Don Zank Sep 10, 2002 Msg # 34977 Re: Stall in a Slip ?? You guys doing slips....just go to altitude and try this stuff. I hate to give advice about exploring the "edges" of what is practical. Someone can always screw up. I can feel every challenger nuance before it happens. I have 4000+ hours in Challengers alone! So be advised that I know what a Challenger can do before the plane does. :) When I show off a plane to a potential customer, especially if he is already a pilot and is not too afraid....I ALWAYS scare em with the slip! Now be advised that stall comes sooner when in a slip and you cannot believe your ASI!! In a max performance slip I am stalled or nibbling at the stall the entire time, with the nose as high as I can keep it. Remember that the stall comes sooner in the slip so merely "kicking" out of the slip will instantly stop the stall! PLEASE, only try this stuff at altitude. Remember also that every plane is just a bit different, so your plane is not some one else's and you gotta have your own answers. Also remember that I am doing this stuff most of the time from the rear seat so the angles are more apparent from there. Course my clip wing personal plane is the all time slip king!! Dual will usually slip more radical than single. DZ Ken Swasas Sept 29, 2002 Msg # 35008 Re: Stall in a Slip ? ? “Has anyone taken a Challenger up to altitude, crossed the controls, and let it stall?” Yeah, sort of. I took a 418 lb 2 place with the doors on up to 5K and did a 3 axis full deflection slip. It came down just fine for the first 2000 feet. The left (up) wing was a little hard to hold up and I was expecting it to drop but it did not stall. At 3000 feet the right (down) wing just started to slowly drop and relaxing the controls did nothing to stop it. Ended up doing a real poor excuse for a split-S and recovered. I have not done one that radical since but am very comfortable with a good hard slip in my plane. I just don't push it that far, and yes, to slip it real good the nose needs to be up a little. When you are ready you might consider taking your plane up and practice the radical stuff up high and the conservative down low. The bumpier the day the riskier it is so use common sense. If I did that test at 100 AGL I would not be bothering you with this little note. PS: I don't care what anyone anywhere says but a fact of life is that first you learn how to fly and then one day you go out and scare the crap out of yourself and become a pilot and fly a little smarter from that day on. Ken Swasas Follow up questions: “Do I understand ... You LOST IT after slipping 2000 ft?” That is correct. All was well then the wing just dropped. Not violent but it slowly dropped. “Did it maintain the heading while failing to lift the right wing, or begin to rotate to the right?” No, it did not maintain the heading. I let it fall through and ended up making about 240 degree turn to the right when recovered. Ken Swasas Time-Out for a comment . . . Why was Ken unable to lift the right wing? Here's an opinion: With full left rudder deflected for the slip and the right wing dropping, you have no way to get the wing back up. Left aileron, to try to lift the right wing, will contribute adverse yaw which will pull the nose around to the right and probably make the wing drop more. And you have no rudder left to use, so down you go! The following posts relate to losing altitude by diving. This exchange followed a series of posts in which various “Masters of the Slip” were citing figures for the maximum rate of descent they could achieve. Larry Davis Sep 10, 2002 Msg # 34995 RE: Real man Stall/Slip Contest J. D. Stewart wrote: I couldn't tell too much from the movies as the camera operator zoomed in on your airplane and it shows little background. That said, from what I could see, slips are not the answer for getting down the quickest. If you ever saw me dive my "heavy"C1 clipped-wing over power wires and down to a runway, there's no comparison. I'll have to make a "movie". :) 100 feet down in two seconds! 3000 feet per minute. :) Full flaperons, at engine idle, and shove the stick forward. Leon Garrett taught me how! :) Larry Davis Jim Hayward Sep 10, 2002 Msg # 35002 Re: Real man Stall/Slip Contest L. D. : “ ... 100 feet down in two seconds! 3000 feet per minute.” That may figure out to that rate per minute for that short a time period but I'd bet you couldn't hold that rate from, say, 3000' AGL to the ground in that time without exceeding Vne or some other no-no. :-) In a slip, you could keep your rate all the way down. Jim H. Larry Davis Sep 10, 2002 Msg # 35003 Re: Real man Stall/Slip Contest I don't know about that! Flaperons maximum speed is 55 mph with "normal" flaperons (mine are not set-up for "full" flaperons) and at idle I don't go much faster than that in a dive. Vne on my airplane is 120 mph and I know I wouldn't go that fast. The flaperons limit dive speed to about 70 mph on my airplane (45-50 degrees). Remember, a C1 clipped- wing is NOT a C2 full wing. A completely different airplane. Bet you've never flown a C1 clipped-wing with a 503, have you? :) Dives like a rock with no float on pull-out. I also know how fast my airspeed is, unlike in a slip. I like that. Plus, I'm not cross- controlled. I like that more. :) Larry Davis Finally, the statement made by Ken Swasas rings so true that I think it's worth seeing again: “I don't care what anyone anywhere says but a fact of life is that first you learn how to fly and then one day you go out and scare the crap out of yourself and become a pilot and fly a little smarter from that day on.” -Ken Swasas It makes the point that a pilot should never become over-confident or complacent when flying. Have fun, but Be Careful ! Author: Doc Green
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