FIRST THINGS FIRST
When performing a graceful maneuver like the loop, focus your attention on geometry and smoothness. When executing the “loop” portion of this aerobatic maneuver, you want a low-rate setting that has about 12 degrees of elevator deflection, 30 degrees of rudder deflection, 25 degrees or more of aileron deflection and exponential on all surfaces. As a starting place, I recommend you use about 20% of expo and increase it until you are comfortable with how the airplane responds. Keep in mind that adding expo will soften the feel of how your servo reacts around neutral.

Let’s now discuss the snap roll. The snap roll rotation should happen relatively fast, and if you find that your model “barrel rolls” around in rotation, you do not have enough control surface deflection and may need different rates on your radio. Most models will snap with about 15 degrees of elevator, 35 degrees of rudder and 35 degrees of aileron throw, but again, values differ from model to model. This serves as an overview, and fine-tuning your model will be up to you. As I mentioned earlier, use exponential and start with a value of about 35% on all control surfaces and then make any necessary adjustments.

When I perform a maneuver like the avalanche, I keep my model on my low-rate settings for the “loop” portion of the maneuver. Then, when I want to initiate the snap roll, I switch to my high-rate setting. I perform the snap and flip immediately back to my low-rate setting for the rest of the figure. To simplify matters, I use flight modes, which means that all rates can be found on one switch!

AVALANCHE OVERVIEW

Until you are familiar with this maneuver, I recommend you climb to an altitude of about 150 feet. Keep in mind, though, that this altitude will vary depending on the size of your model; this starting point is great for an electric model with a wingspan of about 50 inches.

Once your altitude is established and your airplane is traveling parallel to the runway, increase the throttle and begin a gradual loop right when the model passes the pilot (for future reference, the pilot’s position is called the “center”). Keeping the same radius, it’s critical to perform a snap roll at the top of the loop. If the loop began immediately after the model passed the pilot, the snap should be performed as the model is inverted over the top of the loop and at center. Once the snap roll is performed, the model continues the second half of the loop and exits at the same altitude at which the maneuver began.

Now, let’s simplify the control inputs needed and divide this maneuver into four steps:

1 Begin by climbing to a safe altitude and orienting your model so it’s traveling parallel to the runway. The throttle will vary depending on your model’s power-to-weight ratio and the size of your loop. If your model has a fairly equal power-to-weight ratio, you’ll need to use maximum power, especially if you want to perform a larger loop. Increase the throttle to about 90% for your first attempt, and wait until the model approaches center.

2 If you’re using dual rates, make sure you’re on your low-rate setting. As the model is at center, gently pull back on the elevator control surface to begin the loop. Geometry is the key, and it’s critical to perform a perfect circle. With that being said, you may need to increase your throttle to keep the speed of the model constant. Also, you may need to make various rudder corrections to keep the model at the same distance from you (nine out of 10 times, you’ll need to apply right rudder due to motor torque). Keep the same radius constant throughout, and when the model is almost halfway through the loop, it should almost be at center, but inverted. This is a key moment to flip to your high-rate settings, or what I call my “snap rate condition.”

3 Initiate the positive snap roll by applying full left rudder, left aileron and up-elevator (if performing the snap to the left; otherwise, right rudder and right aileron with up-elevator). After one complete rotation is performed, neutralize inputs and immediately flip back to your low-rate setting and decrease the throttle to about 10% power.

4 Complete the second half of the loop. When the model is 75% done with the loop, it may be necessary to lower the throttle to idle. However, keep in mind that you may need to increase the power again as you are approaching center (the same point at which the maneuver began).

Now that you have learned how to properly execute the avalanche, let’s discuss a few key tips. If you are flying in an extreme headwind, you may need to gradually pull the model up to initiate the loop and then pull back harder once it has completed the first quadrant, as the wind may push you toward center faster than anticipated. After the snap is performed, you’ll need to pull a little harder on the elevator until you are about 80% done with the loop. You then ease off elevator to complete the maneuver as the model is directly in front of you. Whether you are flying in a head-wind, which we just described, tailwind, or crosswind, it is critical for this maneuver to be centered and performed directly in front of you. Make all necessary adjustments so the model always remains at the same depth from you and that it reaches the cardinal points.

Illustration by FX Models

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THE PLANE
Many models from 40-percent gassers to small foamies are able to do the avalanche.  A model needs only the four basic functions: rudder, elevator, aileron and throttle. Typically, a low- or mid-wing design that doesn’t have much dihedral but has enough elevator authority to do an inverted flat spin and snaps is perfect for these maneuvers.

THE AVALANCHE
The name suggests that it must be a wild 3D maneuver, right? Well, not really. In the world of aerobatics, the avalanche was around long before 3D aerobatics were ever dreamt of. It has appeared in various forms and has been a maneuver in the precision schedules of many F3A, IMAC and TOC competitions.

I’ve often said that even if your interest in aerobatics is only in the 3D arena, learning the fundamentals of flying precision maneuvers will improve your 3D flying immensely. The discipline you gain from flying precision will help make your 3D flying more deliberate; it will have a much more planned and well-executed presentation. Of course, if you do compete or aspire to do so, read on; I’ll describe how to execute the avalanche properly.

WHAT IS THE AVALANCHE?

In simplest terms, the avalanche is a loop with a snap roll at the top. Although this sounds easy, it can be difficult at first, but once you understand the elements of the maneuver and what should be done and when, it becomes quite easy.

THE LOOP

To start, you have to learn how to do the loop properly. A loop is simply a circle done vertically in the sky in the pitch axis of the model. That just means that starting from level flight, pull up-elevator and hold on until the model loops through 360 degrees and returns to level flight.

The Precision Loop

Now let’s take the ordinary loop and turn it into a well-presented precision loop:

• Step 1. Put it in the right place. When starting the loop, the model should be flying parallel to the runway in front of you. Don’t start the loop if the model is flying at an angle toward or away from you. If you do, it will be impossible to see the symmetry of the loop.
• Step 2. Center the loop on yourself. The loop should start just as the model reaches center or is exactly in front of you. Just as it reaches that point, pull back on the elevator.
• Step 3. Shape it right. The loop should be a perfect circle drawn in the sky, not an oval. It should start and end at the same altitude, and when done correctly, it should actually start and end at exactly the same point in the sky, no closer to or farther away from you. Trying to do this may bring some trimming issues to light.

In addition to making the loop perfectly round at the proper location, you also have to make it the proper size, not too small and not too large. If it’s too small, it looks rushed and leaves you little room and time to place the snap at the top. If it’s too large, it becomes more difficult to make the loop round and to hold it in the proper heading. You may also start to run out of power at the top, and that will make the snap roll impossible to do.

The correct size of a loop is determined by the hardware you are flying. A larger airplane with a lot of power will be more natural doing a larger loop than a smaller airplane or one with less power. Experiment with your model until you arrive at the loop that is the correct size for your airplane.

The loop is a simple maneuver, but it is one that you fly through. Don’t pull full up-elevator and watch it go. In fact, you should never be at full up-elevator. Pull back a little, and vary the amount of elevator to make the loop the correct size and shape. Since gravity is at work, you have to pull more elevator at the beginning of the loop than when the model passes through vertical. When the plane goes through the inverted point of the loop, relax the elevator to keep the loop round. As the model starts down the back side of the loop, increase elevator again to overcome gravity and keep the loop round. It’s also a good idea to reduce power as the model starts to come over the top of the loop and down the back side. Full power makes the loop appear rushed, and with larger airplanes, full power in a dive is a big no-no. This could even cause problems such as control-surface flutter and structural failure. Practice doing the “perfect” loop several times until you’re comfortable with it.

ADD THE SNAP

Once you have mastered the loop, work on turning it into an avalanche. Do the same loop, but just as the model reaches the top of the loop, do one snap roll. Stop the snap at exactly one turn, so the model is in the same attitude as it was before the snap. Now reduce power, and complete the loop just as before.

The technique you use to do the snap roll will affect the attitude with which the model exits the snap. The art of the snap roll is a topic that I could easily write an entire article about, but since I don’t have room to go into detail on snap-roll techniques here, I’ll just go into some basics. For now, do the snap simply by cornering both sticks, i.e., full up-elevator, full aileron and full rudder in the same direction as the aileron. Here are some tips for doing a snap roll on an avalanche:

• Don’t throttle back before the snap. This will cause the model to drop its nose through the snap, and it will exit the snap nose down, making it impossible to keep the loop round. Keep the power up until the snap is complete.
• Don’t snap too early or too late. When done properly, the snap should be at the top of the loop. Don’t get trigger-happy and snap while the model is still climbing or wait too long and snap after the model is on its way back down.
• Don’t over- or under-snap. Be sure to stop at one snap. If you over- or under-snap, the wings won’t be level. As you start to pull through the back side of the loop, the model will start to corkscrew unless you first level the wings.

To make the avalanche look its best, here’s a pro tip: always snap away from the flightline. If you enter the avalanche from your right, do the snap roll to the right (right aileron and rudder); if you enter from the left, roll to the left. This makes the model stay in line better and not step in the direction of the snap. The only exception to this rule is if you are flying in a strong cross-wind blowing out (away from the flightline). The crosswind requires you to learn to snap roll equally well to both the left and right, and that’s an important part of becoming a well-rounded aerobatic or 3D pilot anyway.

FIGURE 4 Avalanche

Master the avalanche, and you’ll become a more disciplined pilot who’s in better control of his model.

VARIATIONS
An almost infinite number of variations on the Avalanche can make it much more challenging to do. Through years of aerobatic competition, I’ve had the opportunity to tackle a lot of them. If you want to try more challenging variations on the Avalanche, here are a few good ones:

• Do the same maneuver but start inverted. Make the loop an outside loop, and at the top, do a negative snap (full down-elevator, full aileron and full opposite rudder).
• Do the Avalanche normally but do only two complete snap rolls at the top, or try it inverted with two complete negative snaps at the top.
• Start inverted, and do an outside loop. At the top, do 1  1/2 positive snap rolls so the model stops inverted at the top; then immediately do 1  1/2 negative snap rolls in the opposite direction back to upright, and complete the outside loop. When you do one like that, you need to start the first snap before the airplane reaches the top because the snaps take up so much space. After the last snap, the plane should be over the top of the loop and at the same point past the top as it was before when the first snap was done.
• One of the most difficult variations requires you to start high and do a loop starting from the top; then, at the bottom of the loop, do the snap, and continue back up to finish at the top.

The post Spice Up Your Loops–Fly the Avalanche appeared first on Model Airplane News.

On the other hand, if you wait until the controls are no longer effective to start to add power, you may not recover control in time to save the maneuver. You need to smoothly pump the throttle during a harrier to maintain propwash over the tail surfaces without holding the higher throttle position long enough to cause the airplane to accelerate. The objective is to pump the throttle to maintain control and altitude. The instant you sense the controls becoming ineffective, or if the plane starts to descend, give the throttle a little extra boost. You’ll also find that you can respond more quickly when you’re continually pumping the throttle, than if the throttle is stationary. To maintain the same height during a harrier, the amplitude or range of the throttle movements is usually between quarter and half throttle, with an airplane capable of hovering at half throttle. If you lose complete control at these very low airspeeds, often the only way to regain control/recover is to go to full power.

All the maneuvers featured in this 3D flying series are flown on high rate flight mode.

Elevator technique

Pump the throttle to maintain propwash over the tail and thus control authority without accelerating. Vary the amplitude or range that you pump the throttle to control altitude throughout the harrier pass.

The simplest way to enter a harrier is to slow down to nearly stall speed, and then smoothly pull the nose up to establish a very high angle of attack while simultaneously adding power to maintain the same height.

Continually pump the elevator to maintain an approximate 45-degree fuselage angle during the harrier pass, i.e., raise and lower the nose by increasing and decreasing the size of your elevator adjustments.

While both the left and right wings are deeply stalled during the harrier, they tend not to stall exactly the same, and consequently, the wings tend to rock from side to side. Every airplane has a certain fuse-lage angle or “sweet spot” during a harrier that results in the least amount of wing rocking. That angle is usually close to 45 degrees, and it usually takes about half elevator to achieve it. You will then find that it takes constant elevator adjustments to maintain that angle due to the fact that airplanes are not designed to fly this way. Note that if you are late with any elevator adjustments, it will take a much larger input to recover, thus increasing the potential for over-controlling. Smoothly pump the elevator throughout the harrier to keep your fingers nimble and ready to instantly respond to the needs of the moment. Inputting a series of smaller adjustments, rather than waiting to respond with larger adjustments, ultimately reduces the potential for over-controlling.

Rudder-aileron technique

Hold in right rudder to correct for propwash and P-factor left turning tendencies. Correct deviations with small brief bumps of rudder and coordinate aileron and rudder to keep the wings level.

Rudder is used throughout the harrier to correct course deviations and to steer the airplane. Most of the time, you’ll have to hold in right rudder to correct for the left turning tendencies of propwash and P-factor (asymmetric propeller thrust) encountered at high angles of attack. Use coordinated aileron and rudder inputs to keep the wings level. Note that adverse yaw will be significant any time you apply aileron at high angles of attack, so you must coordinate rudder with the aileron in the same direction when leveling the wings to prevent adverse yaw from causing the maneuver to unravel.

Most important, because airplanes are typically very unstable during high alpha flight, it is crucial that you keep your rudder and aileron corrections small and especially brief (i.e., “bumps”) to avoid aggravating the wing rocking phenomena.

Conventional flying experience teaches us to relax the elevator and lower the nose when the wings start to rock during a stall. Resist the urge to relax the elevator when the wings start to rock during a harrier. Maintaining a high angle of attack can actually work to lessen wing rock by keeping both wings deeply stalled and having as little aerodynamic influence on the maneuver as possible. In other words, sometimes pulling more elevator will lead to less wing rocking.

Elevator-flap mix

An effective technique used to reduce wing rock is to activate the elevator-flap mix so that both ailerons raise up approximately 20-30% when holding in up-elevator. While you’re at it, you might as well program both ailerons to lower 20-30% with down-elevator to compliment future inverted 3D maneuvers (inverted harriers, elevators, etc.).

Harrier turns

Mixing both ailerons up 20-30% with up elevator helps reduce wing rocking at extreme high angles of attack.

Turning while in a harrier attitude consists of steering with the rudder, using the ailerons to keep the wings level, and pumping the elevator and throttle to maintain the same fuselage angle and altitude.

As unstable as an airplane is during a harrier, in order to turn without over-controlling, you must limit your rudder inputs to brief nudges every few moments. Be sure to gently nudge the plane around the turn with rudder while applying opposite aileron to keep the wings level. Attempting to turn with the rudder alone at this high angle of attack would lower the wing on the inside of the turn, and doing this at a low airspeed could cause the airplane to sharply fall off to the side. You’ll need to apply opposite aileron throughout the turn to keep the wings level. Remember, if the wing on the inside of the turn drops, the plane can fall abruptly toward the ground, so always be ready during a harrier to punch the throttle to full in order to help with recovery. Once the turn is finished, continue using the rudder to steer, but switch to coordinating aileron and rudder in the same direction to keep the wings level.

Conclusion

Control the rate of turn during a harrier with rudder, and cross-control opposite aileron throughout the turn to keep the wings level.

Note:If the plane behaves strangely, as if it is responding to alien control inputs, it is most likely that the mix percentages you’re using are far too high. This would explain why odd things are happening during other maneuvers as well.

You should, of course, practice this maneuver on a simulator before attempting it in the field. Even though you will probably find that the simulator has a different feel than real-world 3D flying, sim practice will help sharpen your reflexes and get you in the habit of manipulating all the controls simultaneously. Remember, it helps if you keep your fingers moving when flying 3D and be ready to punch the throttle to full to recover when things unravel. Good luck.
TEXT & ILLUSTRATIONS BY DAVE SCOTT

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When you fly your model at a scale event, you will be faced with variable conditions, including:

• Wind direction. Wind has the biggest effect on models because it can change quickly during the day. It affects takeoff direction and the headings of the maneuvers flown. Plus, it is usually calmer in early morning and windier during midday.

• Position of the sun. The sun’s position often requires you to move your maneuver to the right or left of the flight judges; this is done for safety and is OK with them. But moving your maneuver can throw you off pace a bit and make you a bit uncomfortable.

• Flightline position. If you have to come in over a tree line to land, you may tend to fly the approach higher than normal. If your flight station is also close to the trees, your landings may be slightly past the judges’ centerline. Don’t expect perfect flightline placement.

• Field conditions. The runway can be grass or paved; either surface will greatly affect your model’s ground handling. The length of your takeoff will also be affected by the grass’s length, while paved surfaces are a nightmare for airplanes with non-steerable tailskids.

• Time of day. It might sound silly, but the time of day also has an effect on your flying. Early-morning flights are affected by the dew on the grass; it makes landings slippery. In the afternoon, heat rising off the pavement can cause turbulence. As the day goes on, crosswinds can replace calm conditions.

PRACTICE

To improve your ability to deal with changing conditions, you have to practice. If your club’s field has a grass runway, practice flying from it both when the grass is newly mown and when it’s overdue for a trim. Fly early in the morning and late in the afternoon; practice landings and takeoffs from both the left and the right. Fly on windy days, and when it’s calm. Experience will help you become a better competitor, and being prepared for change often means the difference between an average flight score and a good one.

AVOID CONFUSION

Preparation is a good thing for contestants, but I think it’s equally good for judges. They should be prepared to make allowances for field conditions, weather and unforeseen events. Most important, everyone needs to understand what the various flight maneuvers are supposed to look like and how they should be performed. I think it will be to everyone’s benefit if all participants (judges and pilots) refer to the AMA rules in the most recent Competition Regulations booklet. These guidelines separate maneuvers into three categories that are judged: Precision, Presentation and Realism. For the sake of consistency, give each category some thought (whether flying or judging them). Let’s take a closer look at these important areas to be judged.

• Precision. A contestant should always talk to the judges before beginning to fly and explain what each maneuver will consist of so the judges can form a mental image of the maneuver. Whatever you say you’ll be doing is what the judges will look for, so be certain to do what you said you would do! If you say that your Ju-87 Stuka dive-bomber will perform a 90-degree bombing dive before it releases its bomb, don’t dive the model at a 75-degree angle. Judging begins when the contestant announces “Beginning now!”, and it continues until he calls, “Maneuver complete!” After announcing the beginning of the maneuver, fly a straight course for about 50 feet before actually performing the maneuver. Do this at the end as well; fly 50 feet along a straight path before calling the maneuver complete. If done in a smooth, prototypical manner, course corrections are downgraded, but not severely. Most maneuvers should start and finish at the same altitude (exceptions to this are the split-S, 360- degree descending turn, 3-turn spin and the Immelmann turn). Keep your wings level, and don’t make abrupt altitude or heading changes during your maneuver. To maximize your precision score, you want to perform centered and balanced maneuvers.

You can’t give the flight judges too much information before your flight. Don’t just say you’re going to execute a roll—be specific! Will it be a barrel roll or an axial roll? What should the judges look for? If you tell them, your score will be higher.

• Presentation. I love this part because it is so basic. For a maximum score, present your maneuvers so they can be judged easily. The best place to perform a maneuver so the judges have the best view of it depends on which maneuver you’re performing. For a clear view, a stall turn or a wing-over should be offset to the left or right of the judges. Maneuvers that have horizontal symmetry, such as loops and cobra rolls, should be positioned with their midpoints centered in front of the judges. It is also important to fly above the runway’s centerline or at the proper distance from the judges, as stated by the contest director (CD). This is an important safety issue, so pay attention at the pilots’ meeting.

If you move your maneuver to the left or the right of the judges because of the sun’s position, be sure to explain what you are doing. If you fly through the sun, you can receive a severe downgrade. Your presentation will also be affected by the aircraft you fly. A fast-moving jet or WW II fighter is best presented at a bit of a distance from the judges. Slower WW I or civilian aircraft benefit from being flown closer.

• Realism. It is difficult to explain how realism is scored because it is so subjective. To maximize your score, fly only those maneuvers that your aircraft was capable of doing in full scale. Hotshot pilots who perform three axial rolls with a model B-29 should expect a downgrade. For better realism, stick with prototypical maneuvers. The size of the maneuver should also reflect the aircraft’s capabilities. A jet could make very large loops at high speed, but performing small, tight loops would result in a downgrade because in the full-size plane, the pilot would have been subjected to high-G forces. A J-3 Piper Cub would be capable of making loops, but because of the Cub’s limited power, the loops would have to be somewhat small in diameter and more oval than perfectly round. A pilot who performed high-speed loops with this type of plane would be significantly downgraded. Aircraft size may also affect a pilot’s Realism score. A 1/4-scale Sopwith Pup is expected to perform larger maneuvers than a 1/8-scale Pup. It is very important to account for the scale size and speed of your plane. Smooth, graceful flight presentations have a great impact on realism. Judges often pretend to be passengers in the aircraft they are judging. Jerky, bumpy flying is unrealistic and will hurt your flight score. Abrupt takeoffs and landings also cause downgrades.

COMPILATION

Placement, Presentation and Realism make up equal parts of the flight-scoring process. At some events, Realism is treated as a separate flight maneuver worth 10 points, and it is evaluated during and between each maneuver you fly. These 10 points are more of an overall grade of how realistically you performed with your aircraft. In general, flight judging is more difficult than static judging because it relates to how we think the prototype aircraft flew. When your model is static-judged, it is compared to your documentation booklet and your 3-view drawing. If you talk to the flight judges beforehand and tell them what your maneuvers will look like, it will help them to score you more consistently. Are there other factors that affect flight scores? Yes; the basics—being polite, being organized and being ready to fly when you’re called to the ready box—will undoubtedly help. Improving your flight score is an ongoing process.

THE JUDGES’ POINT OF VIEW

Let’s face it. Flying in competition isn’t easy. The AMA rulebook covers scoring downgrades quite specifically, but when it comes to Presentation, I feel that the judges should focus on maneuver position using three references: looking upward, looking to the sides and looking straight ahead. I prefer to work with 1/4-point deductions because they are fairer to pilots who fly many different types of airplanes.

Figure 1 shows how two judges sitting together can have varying perspectives when viewing a maneuver that’s being performed right in front of them. Each judge should be aware that a maneuver that appears to be to his right or left may actually be placed correctly in the center. I don’t think this “middle ground” should have any downgrades applied for placement, and each outer area should use an ascending Vi-point deduction.

Figure 2 shows a side view that uses a 45-degree angle to establish its upper boundary. Downgrades are given for flying above it or for flying too close to the judges. Again, there are no downgrades for flying below the 45-degree angle. If a pilot performs a stall turn, a spin, or a specific high maneuver, and the highest part of his maneuver is above the 45-degree angle, his score is not downgraded.

Figure 3 shows what the judges see when they look straight at the flying field from their seats. Each maneuver requires its own interpretation for the “ideal flying zone,” but once that has been done, all downgrades should follow the same standard. By using Viewpoint downgrades, a judge can determine if the maneuver is positioned too far off center, too high, too low, too far away from the flightline, or if it is too large. If we keep in mind that the pilot must still perform his maneuver with regard to perfection and realism, I think the 1/4-point deduction system is a fair way to score.

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STEPS TO SUCCESS
Step 1. Start the maneuver by flying at full power, straight and level, with the wind or downwind. Apply up-elevator as if you’re going to do a loop.

Step 2. Continue the loop until the plane is inverted and heading downward at a 45·degree angle. As the plane goes over the top of the loop, release elevator and reduce power; if you don’t, it will pull the plane off to one side during the roll. Be sure to keep the wings level during the loop.

Step 3. Apply aileron and roll upright. After doing the roll, let the plane continue downward until it is at the same altitude as when you started the maneuver.

Step 4. Add throttle and up-elevator to start the second half of the maneuver and perform another loop and 1/2, roll and finish the maneuver in the same way as you did the first half.

Step 5. When you exit, you should be flying in the same direction and at the same altitude as when you started.

PRO TIPS
• As you become more proficient, make the loops larger and pause for a second before the roll. Try to place each roll at the same altitude so the maneuver looks symmetrical .

• Try a reverse Cuban-S and do the roll first. Start at a safe altitude, and apply up-elevator to make the plane climb at a 45-degree angle. Roll to inverted, decrease throttle to idle and pull up-elevator until the plane completes the first part of the loop. Recover, then increase power and do the other half of the maneuver in the same way you did the first.

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After the airplane has made it past the top of the loop, idle the engine to slow the descent and get ready to quickly neutralize the elevator at the instant the plane points straight down. Despite the throttle reduction, airplanes tend to quickly build speed when pointing straight down, so hold the lines before and after the half-roll no longer than a count of “one.” Flying a perfect vertical downline is the mark of a professional-caliber P loop. If you do not have the time to display at least short vertical lines before and after the roll, you’ll have to enter the maneuver higher and/or fly much larger loops to enter the downline higher up. You think of it this way: if you don’t have enough altitude to dive straight at the ground, perform a half roll and pull out, you probably don’t have enough height to perform this version of the P loop. This is what we mean when we talk about “thinking ahead of the airplane!”

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The reason I am explaining this is simple. Too many times, I see pilots trying different and extreme maneuvers and oftentimes the airplane is in control, but not the pilot. To become really successful we must stay in control and this requires lots of practice.

Maneuver breakdown

For this maneuver, the pilot enters from inverted flight and pushes to establish a 45-degree climb then he performs 1½ negative snaps. After the snap, another line segment (equal to the first line) is then executed. Once the maneuver is complete, the pilot must pull 135-degrees to exit in inverted straight and level flight.

This is a good maneuver to help teach you how to perform cleanly while being aware of any corrections being needed for maximum points. As with most maneuvers, with lots of practice, you learn to correct subconsciously which is the goal for anyone wanting to be a serious aerobatic and or 3D pilot.

Enter Inverted straight and level

1 Apply about 80% power and push to an inverted 45-degree upline.

2 After a straight line segment of about 75 feet, switch rates and perform 1 1/2 negative snap roll.

3 After the snap, switch rates to low, reduce throttle and maintain straight, upright line segment (75 feet).

4Pull up-elevator to perform 135 degree radius and establish inverted flight.

Exit Inverted straight and level

Maneuver overview
Climb to a safe altitude, roll to inverted, line up for the maneuver flying parallel to the runway and apply about 80% throttle. Push gently and establish a 45-degree inverted climb. After the radius and the climb is established, note the flight distance before the 1½ negative snap is started. You will have to fly a similarly long inverted flight segment after the snap roll. I usually count to myself and for this maneuver, a two-second segment seems about right. Flip to your Snap Mode and, all at the same time, apply down-elevator and opposite rudder and aileron. After the snap segment is complete, neutralize your inputs to establish a 45-degree upright climb. If you fly at a constant speed, then count to yourself again for two seconds. Now, pull 135 degrees to exit the top of the maneuver straight, level and inverted.

By the numbers

STEP 1: Enter the maneuver inverted and parallel to the runway. When ready, make sure that you apply at least 80% throttle and push down-elevator, ever so slightly, to perform a smooth radius and establish the 45-degree inverted climb.

STEP 2: After a line segment of about two seconds (about 75 feet in length,) flip to “mid-rate” and perform a 1½ negative snap roll. The key to performing the snap roll properly is timing and setup. If your airplane becomes too “deep” in pitch and is difficult to stop constantly on a 45-degree climb, you may need to dial the elevator rates down a touch. Also, for this segment of the maneuver, you may need to either increase or decrease the throttle to maintain constant flight speed.

STEP 3: After the snap roll, flip back to the “low-rate” setting, and perform a line segment that is equal in length to the first. Balance the throttle, as needed, so that the airplane maintains a constant flight speed and apply rudder input, if needed, to keep a constant heading. In a crosswind, you may notice the nose of the aircraft drifting into the wind. You will have to use just enough rudder to correct.

STEP 4: Exit at the top by pulling 135 degrees to establish inverted level flight. It will be necessary to hold a touch of down elevator to keep the altitude constant. You model’s CG location with affect how much down elevator is needed. Nose-heavy airplanes require more elevator input.

Like I mentioned earlier, it is important to take small steps to accomplish your goals and perfect a new maneuver.

BY JOHN GLEZELLIS; ILLUSTRATION BY FX MODELS

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