We stand, shoulder to shoulder, gazing up at the sky. With a hand shielding our eyes from the sun, we watch the smoke trail of an airplane flying up, up and over into a perfect loop. A vertical circle in the sky, a loop is a loop, whether flown by a biplane or a Bearcat. Diving for speed, the pilot pulls the stick back and the airplane goes up. It floats over the top and gravity brings it back down, the pilot pulling to level flight.
There’s some controversy about who actually flew the first loop. Credit goes to two early aviators, a Russian by the name of Pyotr Nesterov and a Frenchman, Adolphe Pégoud. In 1913, Nesterov flew a loop in a Nieuport IV monoplane at an airfield near Kiev and was promptly arrested for “risking government property.” Several weeks later, Pégoud performed the first “official” loop in a Blériot model XI, after which time Nesterov was promptly released, given a medal and promoted to Captain! After, the two incorporated aerobatics into the flight training curriculum, a move that had lasting effect on how pilots are taught to fly. The Nesterov Trophy is given to the winning men’s team at the World Aerobatic Championships.
There are only three core basic aerobatic maneuvers that all the others are based on—the loop, the roll and the spin—and these are the first maneuvers a student learns. It’s easy to do a loop. Dive for speed to around 20 knots above cruise speed, then pull back on the stick. At the apex, or the top of the loop, relax the stick so the airplane doesn’t stall; then as gravity does its thing and pulls the airplane back to earth, pull on the stick to bring the airplane back to level flight.
It’s hard to have too much speed to enter a loop, but it’s easy to be too slow. The airplane has to have enough speed to get “over the top,” a function of how much G-force is available. Cornering speed is the minimum airspeed at which the maximum allowable G can be generated. So, for example, at 100 knots in an Extra, you might be able to get 3.5 G’s. In a Super Decathlon at 100 knots, you might only be able to get a maximum of 2.5 G’s, and that will barely get you up and over. When the airspeed is slow, it takes “finesse” to eke out the performance needed to get you up and over the top.
“Feel” and intuition are important in aerobatics, as they are in much of aviation. I don’t think a pilot should necessarily try to think like an engineer. I suppose there are equations and mathematical formulas for the exact speed and G-force needed for the trajectory of a perfect loop, but conditions are always changing and there are so many variables—wind, humidity and density altitude. No two days and no two loops are ever exactly the same, and maybe it’s because of this that I still find aerobatics compelling and challenging.
It’s fun to experiment with entering maneuvers at slower speeds. The worst thing that can happen? The airplane stalls. If that happens, the pilot just has to relax the stick to reduce the angle of attack, get some airflow over the wings and continue to fly the airplane. People sometimes think that because the airplane is inverted with reference to the ground at the top of a loop, if they get too slow it will go into an inverted spin, but that’s not the case. The airplane may be inverted, but it’s loaded with positive, not negative G, so if anything, it will enter an upright spin. In fact, the airplane can get very slow at the top of a loop without stalling or spinning.
There are loops and then there are round loops. To make a loop round and, well, loop-like, it must be flown with a linear flow and control feel. After you pull back on the stick to enter the loop, you can’t continue to pull the same amount of G all the way around because the speed is decreasing. If you pull 5 G’s with an entry speed of 160 knots, you won’t be able to pull 5 G’s at the apex with a speed of only 100 knots. The pilot has to relax the stick pressure before the top of the loop; then, as the airplane starts downhill again and the speed is increasing, the pilot needs to increase the back pressure so not to over-speed the airplane and to keep the loop round. While the rudders and ailerons stay constant, your hands are always moving the elevator, and the challenge becomes how smoothly you can do it and how well you can “feel” it. If the pilot doesn’t smoothly apply and relax the stick, the loop will be “segmented,” and many a judge has downgraded a loop for this sin, as it disrupts the harmony and grace of a perfect figure.
Much of flying aerobatics is learning where to look during the maneuvers. When you pull back on the stick and the nose leaves the horizon, there’s nothing to see but sky, so the aerobatic pilot learns to look left at the wingtip, or a “sighting device,” a triangle that’s attached to the airplane giving a reference to the horizon. The earth and sky can switch places, but the world revolving around our wingtip is always constant. Nearing the top of the loop, the pilot transitions their gaze to the horizon above them so they can see their position and wing alignment, and then they can see the ground all the way back to the horizon and level flight. I like to demonstrate to students that if they look at the wingtip all the way around a loop, it will draw a tiny depiction on the horizon of the actual shape of the loop.
A loop is a loop is a loop. Or is it? Why does one loop shine and another look ordinary? Why does one come off the level line and enter the loop with panache, and one doesn’t? How do we take things to the next level and elevate the mechanical into artistry?
A roll on top of the loop is one of the most fun things to do. After starting the roll, the airplane will be upright instead of inverted at the very top of the loop. You have to adjust your roll rate each time so you start and end the roll at the same position on each side of the loop, so the speed at which you roll determines where you start it. If you roll slowly, you’ll start early on the loop. If you roll fast, you can wait to roll until you’re almost at the apex. As you get more advanced, you can do multiple rolls or point rolls or an “Avalanche,” which is a snap roll on top of a loop. When rolling on a loop, you have to keep your eyes “ahead” looking in the direction of where you want to end up. I say, look where you want to go and the airplane will follow. At this point, flying a good loop has to be second nature, and then you do whatever it takes with rudder, elevator and aileron to keep the airplane rolling and on heading.
Once you know how to do a well-rounded loop, it won’t be perfect for long unless you correct for the wind. This is where “feel” develops and “artistry” begins. The wind can blow from 360 different directions; a headwind or tailwind can affect the shape of a loop, and a crosswind can be used to correct your heading so you aren’t drifting out of the sight of judges or spectators. If you start a loop into a 20-knot headwind, the top of the loop will become “elongated” if you don’t adjust for the extra airspeed, so you don’t “float” the top as much. Entering a loop with a 20-knot tailwind will “compress” the top of the loop unless you add some extra “float” in it. With a crosswind, you can crab into the wind during the loop to keep it in the same position relative to the ground. You start by crabbing into the wind, but when you get to the top of the loop, the direction of the crab will change, and then change again as you complete it. This is a great exercise for coordination, situational awareness and taking your flying to the next level.
A loop is a loop is a loop. Or is it? Why does one loop shine and another look ordinary? Why does one come off the level line and enter the loop with panache, and one doesn’t? One scores a perfect 10 and another an 8.5 when they both look round. It’s hard to define, but even an airshow audience can tell when a loop is merely good or really extraordinary. How do we take things to the next level and elevate the mechanical into artistry? A loop isn’t hard to learn, but for the mechanical to become finesse and further, art, it takes not only practice, practice, practice, but imagination and confidence.
We begin with teachers and mentors, and by watching those whose styles we want to emulate. If we’re lucky, we have good teachers and we follow in their footsteps. We learn from our mentors, and if we’re lucky, we have many mentors who each teach us something valuable, but eventually we have to “find ourselves” and discover our own inner gifts, nature and essence, and allow those traits to come out. Individual style develops when we have the ability and then the confidence to allow our personality to shine through.
You can think about and analyze a maneuver forever, but it won’t necessarily take you to the next level. To become an artist, a master, you have to move beyond conscious thinking to the other side of intuition and feel. Practice makes better, better gives us confidence, confidence allows us to fully use our own gifts and personality.
Perhaps our relationship to our sport or activity needs to change by disengaging the conscious thought, analysis and ego, and allowing ourselves to imagine more. Clint McHenry used to tell me to “picture” my maneuvers, to use my imagination to see how they looked from outside the airplane. At an airshow, I don’t have to see the color of an airplane to know who the pilot is. I know the personalities. The styles are very distinct, as are the loops and rolls. An airshow pilot at the top of their game has evolved their sport into art.
People often ask me what my favorite maneuver is—a tumble, a lomcevak, a torque roll or a complicated rolling loop—and my response is invariably, I like them all, but finding the precision and perfection of a perfect loop is what I live for. I guess you could spend your whole life perfecting a simple loop. A loop is never just a loop.