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slow roll in a super decathlon
I'm curious to know how others do slow rolls in a Super D. I learned to do
them without rudder. I was told that for a full deflection slow roll, no rudder is required. To me, they look fine. I draw the lolipop on the horizon. It just seems odd that they don't require rudder. Here's how I do them. 1. Establish entry speed, 130 mph. 2. Pitch slightly nose high, neutralize, then full deflection. 3. At 90 degrees, vertical bank, begin slow push. 4. At 270 degrees start stick back. 5. Roll level. TIA |
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On Tue, 23 Aug 2005 00:21:29 +0100, Nobody wrote:
I'm curious to know how others do slow rolls in a Super D. I learned to do them without rudder. I was told that for a full deflection slow roll, no rudder is required. To me, they look fine. I draw the lolipop on the horizon. It just seems odd that they don't require rudder. Here's how I do them. 1. Establish entry speed, 130 mph. 2. Pitch slightly nose high, neutralize, then full deflection. If it is with full deflection, it's not a "Slow Roll" (even if is takes an age compared to other types). If you don't need rudder, you're not rolling slowly enough. 3. At 90 degrees, vertical bank, begin slow push. 4. At 270 degrees start stick back. 5. Roll level. TIA -- ....And so as the little andrex puppy of time scampers onto the busy dual-carriage way of destiny, and the extra-strong meat vindaloo of fate confronts the toilet Out Of Order sign of eternity... I see it is time to end this post. |
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The term "slow roll" gets interpreted different ways. In competition
aerobatics there is nothing slow about it and rudder is absolutely required because it is really a "roll around a point." That is to say that you use the controls to keep the nose pinned to a single point rather than draw an ellipse with it. Of course you can slow the roll rate (useful in training) but you cannot keep the nose on a point without rudder. Its been a few years since I had a Decathlon but I don't remember it lacking adverse yaw. Hard to imagine any uncoordinated rolling maneuver works very well.. Doug Carter Pitts S2-C In article , B S D Chapman wrote: On Tue, 23 Aug 2005 00:21:29 +0100, Nobody wrote: I'm curious to know how others do slow rolls in a Super D. I learned to do them without rudder. I was told that for a full deflection slow roll, no rudder is required. To me, they look fine. I draw the lolipop on the horizon. It just seems odd that they don't require rudder. Here's how I do them. 1. Establish entry speed, 130 mph. 2. Pitch slightly nose high, neutralize, then full deflection. If it is with full deflection, it's not a "Slow Roll" (even if is takes an age compared to other types). If you don't need rudder, you're not rolling slowly enough. 3. At 90 degrees, vertical bank, begin slow push. 4. At 270 degrees start stick back. 5. Roll level. TIA |
#4
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To me, it doesn't seem to have much adverse yaw at all. Perhaps I'm simply
not noticing it due to the grand scheme of things, i.e. being a little new to being upside down, etc! Point taken, i'll check for yaw. That, to me, is a minor point to my overall question. It appears as if I'm doing this manuever very wrong. More importantly, I'm curious to know how to proceed. I presume I should slow the roll rate to a point where, if not compensated with top rudder, the nose would drop? Is there a (practical) point at which the roll rate is too slow? Many Thanks, "Doug Carter" wrote in message . net... The term "slow roll" gets interpreted different ways. In competition aerobatics there is nothing slow about it and rudder is absolutely required because it is really a "roll around a point." That is to say that you use the controls to keep the nose pinned to a single point rather than draw an ellipse with it. Of course you can slow the roll rate (useful in training) but you cannot keep the nose on a point without rudder. Its been a few years since I had a Decathlon but I don't remember it lacking adverse yaw. Hard to imagine any uncoordinated rolling maneuver works very well.. Doug Carter Pitts S2-C In article , B S D Chapman wrote: On Tue, 23 Aug 2005 00:21:29 +0100, Nobody wrote: I'm curious to know how others do slow rolls in a Super D. I learned to do them without rudder. I was told that for a full deflection slow roll, no rudder is required. To me, they look fine. I draw the lolipop on the horizon. It just seems odd that they don't require rudder. Here's how I do them. 1. Establish entry speed, 130 mph. 2. Pitch slightly nose high, neutralize, then full deflection. If it is with full deflection, it's not a "Slow Roll" (even if is takes an age compared to other types). If you don't need rudder, you're not rolling slowly enough. 3. At 90 degrees, vertical bank, begin slow push. 4. At 270 degrees start stick back. 5. Roll level. TIA |
#5
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Below I've pasted in part of a tutorial I did on slow rolls for the flight
sim community on the Griffon Spitfire package from RealAir. The tutorial is patterned after the way I did slow rolls while demonstrating the P51 Mustang in real life, but you will find the information pertains to a Pitts or the Decatholn as well. Hope it helps a bit. Dudley Henriques Slow Rolls in High Performance Prop Fighters Dudley Henriques International Fighter Pilots Fellowship With the entry of the Realair Griffon Mk 14 Spitfire into the WW2 military market for MSFS, a whole new world of flight experience is now possible in MSFS for those sim pilots interested in this area of aviation. I receive a lot of email from sim enthusiasts asking me for information about the technique required to fly the hot prop fighters. Since I did a fair amount of this type of flying in real life, I try and answer these requests when I can. It has occured to me that you folks at Avsim might wish to share in this information, so I’m pasting in this tutorial for you as well. I sincerely hope this information serves to make your flight simulation experience more educational and enjoyable. This tutorial deals specifically with the slow roll, which I touched on in an earlier tutorial about rolls in general. From my mail it has become apparent that a more detailed tutorial on doing slow rolls specifically in prop fighters, in particular the Realair Griffon Spitfire, might be helpful. Along those lines, I have prepared the following information for those of you who have the Spit, or are possibly thinking about purchasing this absolutely marvelous and beautiful addition to MSFS. First off, let me say a few things about controllers used in the sim and aerobatics. A slow roll requires some cross controlling, and this is best accomplished with a stick, separate throttle, and rudder pedals. I realize that some of you don’t have this. I’ll explain the roll using the optimum controller setup and those of you using other controllers can “adjust” to do what’s necessary with your individual controllers. Actually, aside from a slow roll, a hammerhead, snap rolls, and spins, you single controller folks can do almost anything else in the book; Aileron Rolls, Loops, Cubans, Reverse Cubans, Barrel Rolls; almost anything that doesn’t require cross controlling the airplane, so don’t dispair. There’s enough aerobatics in the book for everybody I did try a slow roll with a Sidewinder , and although it was unusual, I could do it all right. practice is the key. The following is a tutorial on how to fly a good slow roll in a prop fighter. Although it’s edited for the simulator, it basically contains the same information I used in demonstrating these airplanes in real life. To understand the slow roll is to understand the airplane and proper control use. Of all the aerobatic maneuvers possible, the slow roll is perhaps the hardest to master. It requires flying the airplane diliberately and smoothly through 360 degrees on it’s longitudinal axis. It requires placing the airplane at an exact place in the sky and keeping it there through control use that is totally unique to the slow roll, and in many cases completely foreign to a pilot’s natural instinct as that instinct relates to coordination. To fly through a slow roll correctly requires a high degree of concentration and skill. Although a slow roll can be executed from almost any flight attitude, I will use a level flight entry for our example. If you can perform a level slow roll, you can perform one anywhere in the flight envelope. The first thing we learn in discussing rolls of any kind in a high performance prop fighter is that the direction of prop rotation establishes what we call a torque side. What this means basically is that due to the various forces in play with propeller rotation and engine combination, a prop fighter is “handed” with a side that will result in a faster roll rate available to a specific side. In the P51 for example, the propeller rotates to the right as seen from the cockpit. The torque side for the Mustang is the left side. It rolls faster and easier to that side. The reverse would be true for the Griffon Spitfire, as it’s Rotol propeller rotates to the left, making it’s torque side the right side. It rolls better to the right. Now, using the Griffon Spitfire and rolling to the right, let’s visualize where we have to put the airplane in the sky to do a decent slow roll. Visualize a capital letter D. This is the key to visualizing our slow roll. The first thing we learn here is how that letter D relates to the roll. Imagine a horizontal line going right through the center of this D from left to right like this -------D-------- . That line is the horizon. Now let’s define how this D relates to the nose attitude of the Spitfire from start to finish through the roll. The vertical line of the D on the left side represents the nose attitude at the bottom of that line for level flight below the horizon. The top of that vertical line represents the distance above the horizon where we will execute the first half of the slow roll; from right side up to inverted. Now notice the curved line on the right side of the D. That line represents the second half of our slow roll. The reason we have to raise the nose to do the first half of the roll is because the Spitfire, and most any WW2 era prop fighter will have a higher nose attitude inverted in level flight than for normal level flight due to a required higher angle of attack on the wing in inverted flight. The reason for the curve on the D is because the airplane has to return to it’s normal level flight nose attitude below the horizon line at the completion of the roll. So what have we learned right off the bat? The roll isn’t done in level flight at all. It’s done by raising the nose to a distance equal above the horizon to where it is normally in level flight below the horizon.. Then after rolling inverted on the exact top of that vertical line of the D, we perform the second half of the roll allowing the nose to return to level flight below the horizon. Got the visualization?? Now, how do we do all this? First, let’s climb the Spit up to 5000feet and level off. Bring the power back to about 0 boost with the prop in automatic. Stabilize the airplane in level flight at cruise. Now, let’s learn to do a slow roll the right way. For ease of explanation, I’m going to take the slow roll and split it into conveinent sections of 45 degrees each so we can examine the control inputs vs the roll as it progresses. We’ll have the first 45 degree point, the second 45 degree point at the first knife edge at 90 degrees, the third 45 degree point (at 135 degrees), the forth 45 degree point at full inverted at 180 degrees, the fifth 45 degree point (at 225 degrees into the roll), the sixth 45 degree point at the second knife edge at 270 degrees, the seventh 45 degree point (at 315 degrees into the roll), and then back again to level flight. Keep in mind this isn’t a hesitation roll. I’m just using the points for reference during what will be a smooth continious fluid maneuver without hesitation from start to finish. In the Spitfire, you want an entry airspeed of 250MPH IAS for the roll initiation. The secret in doing aerobatics in a warbird of any kind is smoothness. There should be no quick movement of the controls, either in real life, or in the simulator. Now, ease the nose down gently and pick up your entry speed at 250. The nose will now be lower than your normal level flight attitude below the horizon. Remember that vertical line on the D. You’re starting a bit below the bottom of that line, but where you want to put the nose at the top is equal above the horizon line to where it was in NORMAL LEVEL FLIGHT, not where you’re beginning the roll! Now, gently raise the nose and go up the vertical line of the D and PIN IT at the top. In the Spit, this will be about 20 degrees above the horizon. THAT SPOT is where you will do the first half of your slow roll by PINNING the nose right at that spot as you roll through the first 180 degrees of the roll. Now, you set the nose by neutralizing the controls for just an instant. You want all back pressure removed from the stick...NONE! Now let’s stop right here for just a moment and discuss what happens as you initiate the roll. We’ll be rolling to the right for two reasons. First, it’s the Spit’s torque side and the roll is easier in that direction. (You should also note that the Spit will roll quite nicely to the other side, but without the aid of the prevailing torque forces) Secondly, because our capital D defines a roll to the right and is easier to visualize as a teaching aid. It helps a great deal here if you completely understand what happens in the roll entry and how you can take advantage of what happens. This next sentence is VITAL, so memorize it cold!! In a slow roll, you will be applying aileron at a constant smooth and steady rate until you are at max deflection. You will be VARYING control inputs for the elevators and rudder all through the roll while changing rudder from one side to the other. This can take some practice to do well, so don’t get discouraged. PRACTICE!!! As you apply rolling aileron (right in this case) you will generate adverse yaw to the left. A slow roll entry gives us a very interesting situation. To counter the adverse yaw, we need right rudder applied with the aileron. That will take care of a coordinated entry, but if we hold that right rudder in there too long, we’ll begin to pull the nose down, which is exactly what we DON’T want to do. We want the nose pinned; so how do we do this? Ok...we’re applying right aileron and just a touch of right rudder to coordinate the roll entry.......then almost immediately, we switch feet and go to the left rudder. This holds the nose up during the first 45 degrees of roll. As we pass through 45 degrees, we’re applying aileron and now entering some forward stick with the left rudder. If you visualize what’s happening to the airplane, you will see that the left rudder is taking the role of the elevators during the first 45 degrees of the roll and holding up the nose. Now as you go through that 45 degrees of roll, the forward stick is helping the rudder keep the nose pinned. You are in effect trading off the elevators and the rudder as needed to keep that nose pinned where it is AS you are applying the aileron, which is the control producing the roll!! Remember....it’s the aileron that is producing the roll. Keep the aileron applied!!!!! Now, we’re at the first knife edge. Here you should have maximum left rudder and some forward stick. As you roll past knife edge, the STICK FORWARD now becomes the prime control keeping the nose pinned ss the elevators are now holding the nose up. You apply as much forward stick as you need while keeping the aileron applied to max at this point. The stick should be well in the right front corner of the cockpit by now and you should have on left rudder. As the roll goes through the .next 45 degree point, you are headed toward inverted at the top of the roll. You now have to begin coming off that left rudder timing it so that you are exactly at a neutral rudder as the nose passes through the inverted position. Now.....(and you thought this was going to be easy ))) As the airplane passes through inverted flight at the top of the roll, it will be, (if you have pinned the nose correctly that is) at it’s natural nose attitude for inverted flight above the horizon an equal distance that it would be below the horizon in normal level flight. Now, you switch rudder to the right rudder as you are holding in forward stick and rolling aileron. Now you are starting the airplane down from the top of the roll and back down that curve in the D toward level flight again. You’re rolling and letting the nose come down by easing off the inside rudder and forward stick to time everything to again be neutral as the nose returns back to level flight. By easing off the forward stick and the rudder, in effect, the last part of the roll will be just like a turn recovery. Getting this exactly right takes practice. Well, you now know how a slow roll is done in a Griffon Spitfire, or in any WW2 era prop fighter for that matter. I sincerely hope you get interested in this type of flying. It’s different. It’s unusual, it's challenging, and it will produce for you a great deal of flying education. End of tutorial "Nobody" wrote in message ... I'm curious to know how others do slow rolls in a Super D. I learned to do them without rudder. I was told that for a full deflection slow roll, no rudder is required. To me, they look fine. I draw the lolipop on the horizon. It just seems odd that they don't require rudder. Here's how I do them. 1. Establish entry speed, 130 mph. 2. Pitch slightly nose high, neutralize, then full deflection. 3. At 90 degrees, vertical bank, begin slow push. 4. At 270 degrees start stick back. 5. Roll level. TIA |
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