Figure 2 is an "N" figure, starting with a pull to vertical up. This figure should start near the downwind side of the box to give you time to set up the spin in figure 3. Make the pull to vertical and get your roll in the middle. I use a quick 3 count, 1/2 roll and then a quick 4 count. My Pitts S-2B count was a fast 1-2, roll, 1-2-3. Be very careful in the roll that you don't allow the airplane to go positive or negative in the roll. When setting the initial vertical up line, be sure to "unload" the wing by pushing very slightly on the elevator. This helps to prevent pitching or barreling in the roll. After the count, push to the 45 down line. It is better to push over the top with a little more speed, than too little. With too little airspeed left, even if you set a 45 degree line, the airplane will settle on a steeper line that the judges will see. At this point, in my airplane, I close the throttle to descend back lower in the box. Again, in a Pitts, leave the throttle open. This makes things much simpler for the Pitts pilots. On the 45 down line, make your count to your snap speed, again about a 4 count. Make the full snap, and set the 45 line again for a 3 count, then pull to vertical. Be sure you get your anti-G strain maneuver going BEFORE you start the pull, this is a long, high speed pull with lots of Gz. Set your vertical line, and get the altitude you need for the spin. The altitude for the spin is a critical altitude, so be very sure you hit this critical altitude window. Closing the throttle is easy if you might be high. For most of us, we need to set the finish altitude of figure 1 to meet this window. There are not many changes you can make in figure 2. Cap off on the top of the up line in figure 2. I generally push to level flight from 90-80 Kts while closing the throttle partially. That gives me about 60 Kts in level flight, so I can position the spin where I want it, just by closing the throttle. I like 3,000 feet initially for spins, so I can lose 1,500 feet during the spin and still have plenty of altitude. I do think later this spring, after some more practice, I will be able to use a 2,500 foot spin altitude, so the 1/2 loop next is not too high.
Figure 3 is the 1 1/4 turn spin. Once capped off from figure 2 at a low speed, drive all the way to the upwind edge of the box, and enter the spin. The next figure, 4, is a 1/2 loop up with a 4 point roll on top. This figure is flown on the Y axis, so I will take the spin in the direction of the downwind on the Y axis, or toward the smaller side of the box. That will leave more room for figures 4 & 5 next. Complete the spin, and pull out level on the Y axis. Once again, you are moving at high speed, so give a quick 2 count, then pull for figure 4. This spin and figures 6 & 7 should set the lowest altitudes of the sequence. The initial starting height of figure 1 may need to be adjusted to keep these figures above the floor of the box.
Figure 4 is a 1/2 loop up on the Y axis. Start the loop as near the edge of the box as you dare. You will need the room for the roller later. Also, don't drop a wing or yaw in the pull as the judges will see it. At the top of the loop is a 4 point roll, finishing inverted. Be sure you hit the points, as well. Also, if there is any X axis headwind blowing, the spin and 1/2 loop up will be moved toward the downwind side of the box.
Figure 5 is a 3 roll roller, with rolls to the inside. This figure starts and finishes inverted, so makes seeing your position in the box much easier. This is also a lower speed roller, so it should be easier to keep it in the box, but don't get too aggressive, or you will snap out of it. Use whatever technique you have to make the roller symmetrical. I use a combination of looking for my 45 & 90 degree lines and counting each half roll. The counts should be the same, so you will be able to tell if you are getting ahead or behind.
Figure 6 is a push hammerhead with nothing on the up line. Again, be sure you set a good vertical line without going positive. The line up does not have to be long, and won't be very long in a Pitts airframe, just set a good vertical line to the turn. Once the turn is made, there is a 4x8 roll on the down line. This roll takes a relatively long time, so close or significantly reduce the throttle. Make each point show well; a missing point in the roll is a Zero, not just points off the score. This should not be a problem, but ensure the down line is long enough to get energy for another up line in figure 7.
Figure 7 is a pull, push, pull humpty with a 1/4 roll up and a 3/4 snap down. This is perfect for me as using left roll up is the best for the airplane, using torque to assist the roll, which then requires a right snap down. I prefer to snap right, so the left up/right down combination works for me. Again, set a good vertical up, make your count, get the 1/4 roll done, and the second count. For the looping portion of the humpty, just barely push off the line, then let the airplane float toward the top. Once the airplane has pitched to about 20 degrees nose up from the horizon, then increase the push elevator to the stall buffet. The increase in down elevator makes the second half of the loop finish at the right altitude, equal with the starting altitude. Once the vertical down line is set, count to your snap speed, make the snap, and be sure you snap the proper direction. The snap should be opposite the roll up or should rotate initially away from the downwind side of the box. Finish the count after the snap and pull to level. You should have plenty of energy for the next figure.
Figure 8 is a "P" loop. Pull to vertical and set the up line. Don't spend too long on this up line as you need speed over the top of the loop. In the MX2, I use a 3 count, while in the Pitts, I used a 1 count. Like the humpty, don't push hard off the line, just break off the vertical and let gravity push the nose around the top of the loop. At about 10-20 degrees above the horizon, start the 2 point roll. The roll should be centered on top of the loop, and if the "point" of the roll is on top, then some slight up elevator while inverted will keep the arc of the loop going. Also, as the second point of the roll is done, some bottom or down rudder will keep the loop curve going. A ground coach helps a lot to center the roll. Once the roll is completed, float the loop just a little then start the push to finish the loop. At the bottom of the loop, a 2x4 roll completes the figure. Be sure you are level when performing the roll. It can be difficult to set a horizontal line when inverted. Again, a ground coach can help here. I have to pull the throttle in the downward portion of the loop, so that I am not going too fast for the next figure. In a Pitts, there should be no problem leaving the throttle wide open.
Figure 9 is a pull to a 45 degree up line with a 1/2 snap to inverted, then a lay out inverted to the end of the sequence. The count should be a 2 or 3, then the snap, then a 3 or 4 because of the deceleration. There are no good visual cues over the nose on the up line for the snap. There will need to be a healthy push to stop the snap and hold the 45 line. The up elevator used to snap and the deceleration of the airplane will tend to reduce the 45 line. I use the wing tip, sight device and horizon to stop with the wings level and to hold the 45 line if needed. Most pilots tend to get off heading in a 1/2 snap in the direction of the snap. There are several ways to prevent this, so find one that works best for you. Getting a good stall in the Pitts, and then performing the snap reduces the off heading yawing. Other examples are dropping the wing opposite the direction of the snap during the pull. The lowered wing starts he airplane one way and the snap brings it back. I do a "monoplane" style snap which uses opposite aileron during the pull, and initial rudder input, to prevent the yaw from occurring too early. Use whatever works for you, and looks good to your ground coach.
This sequence ends inverted, so be sure you make at least one wing wag inverted to signal the end of the sequence. I have flown this sequence a few times, but as it is still early in the season, there may be some other lessons yet to be learned from this sequence. Start your early practice sessions up high until you learn the low points of your sequence, then move down a few hundred feet at a time.
Have fun, and let me know what lessons you learn, we all can share our lessons to make us all better pilots.
Flying the 2011 Advanced Known Sequence
17 January 2011
The 2011 Advanced Known (or Q for Qualifier flight) is not a complicated or difficult sequence. In fact, for the Advanced level, it is relatively easy. The higher category sequences do require the pilot to think farther ahead in the sequence, so learning to plan for future figures must be figured out ahead of time.
So it is with figure 1 of this sequence. Figure 1 is a Hammerhead with a 45 degree up line between the horizontal start and the vertical. The 45 up line has a 1/2 roll on the line. The down line on the hammer has a 1/2 snap that must be centered on the down line, so we can't just look for an altitude to start the recovery, as the line after the snap may be too long or too short. This down line is the line that must be used to set the altitude for starting the sequence. See what I mean about thinking ahead? In real life, the starting altitude for figure 1 must be determined empirically, that is by trial and error (safely) to finish figure 1 at the altitude desired. This will vary from airframe to airframe, but in the MX2, I can pull for the 45 up line from 1,000 feet AGL. I try to start the beginnings of my sequences with power and near Vne for a couple of reasons. First, use power so the judges can find you. Try finding a glider sometime after it's off the tow; it is very difficult. Second, the first couple of figures set the tone of your flight in the judge's minds. If you enter the box slowly and use timid wing rocks, the judges get that in their heads. If you enter aggressively, with precision and power, that also stays in the judges heads. So if you enter the box near Vne, you will need to determine how high you go in the vertical, and how long the down line can be, still keeping the snap in the center of the down line. This will determine how high to start. But where; left, center, right, in the box do you start the pull?
Depending on your entry speed, the 45 up line should take about 1/2 to 2/3rds of the box, so pull to the 45 soon after entering the box, near the 25 to 50% area. Set the initial pull so you can be sure the vertical part of the Hammerhead is near the upwind edge of the box.
So, to fly the first figure, pull to the 45, count 1-2 quickly, do the 1/2 roll, count 1-2-3 and push to the vertical. You should still have plenty of speed, so the push needs to be aggressive. Most airplanes want to go positive, past the vertical, after a push to vertical, so be sure to stop the pitch when necessary. Drive the vertical up to the pivot point and make the hammerhead turn as normal. Once on the down line, I will close my throttle, so I can make a longer down line without exceeding my snap speed. In a Pitts airframe, leave the throttle wide open. I start a normal count as I close the throttle. My count typically is a 4 count on the initial down line, then add throttle, make the snap, and give a 3 count, because the airplane has accelerated. At the end of the 3 count pull to level flight.
If there is any head wind, you may not have much time after pulling out level from figure 1. That is why you want the hammer near the upwind side of the box. Don't spend too much time on the straight & level, especially if there is a strong wind.