Energy Management

Energy management is a pilot's most important task. From the time we take off to the time we land, we're managing energy. Energy Management, or "EM," is how we harness the four forces of flight---lift and weight, thrust and drag---and turn them into something useful, like speed and altitude. What goes up must come down---a beautiful symmetry of the laws of physics. Energy is life. The engine breathes fire, and the wings take flight on the wind.

Whatever the intricacies of airplane design---mission, type of airfoil, power-to- weight ratio---all airplanes are subject to the same principles of aerodynamics. If we exceed the best angle of attack in a climb, we get "behind the power curve." If we exceed the critical angle of attack, the airfoil won't create lift, and we either stall or have an excessive sink rate. If we have too much speed on approach to landing, we'll be high and won't make our touchdown point. It's all about managing energy, whether we're in a Cessna 172 or a Boeing 787.

When we line up on the runway and smoothly push the throttle forward, the airplane accelerates, and the combination of the power of the engine and wind over the wing creates lift. For a glider on tow, the relative wind over the wing creates lift. Once we're aloft and climbing, the rate of climb is a balance between too much and too little airspeed to get to our desired altitude. When we level off and maintain altitude, the forces of flight are in balance. As we start our descent, we manage airspeed and rate of descent to our point of touchdown. After a few hours in the cockpit, a smooth climbout, cruise and descent are almost rhythmic and become second nature. But, even when we learn the numbers for best rate of climb and best angle, energy management is ultimately an art, not a science. Once we learn the science, we can use finesse and good airmanship to turn it into art. A little more right rudder in the climb makes the altimeter move faster; a slower rate of descent keeps the engine from cooling too fast. A little opposite rudder on final brings the airplane back down to the glideslope. These are the little things that elevate energy management into art.

In "dog fighting," tactical maneuvers used by fighters during combat, the pilot gains advantage over the opponent by maneuvering into a superior position by using EM. The fighter pilot sees the enemy, and it's up to their brain and their hands to discern the angle between them and their opponents, and manage the energy of their airplane in order to get behind them. The ag pilot manages energy in every "crop duster turn," the climb and descent that puts their airplane in the proper position with reference to the ground without hitting an obstruction. Race airplanes are masters of EM. They're obsessive about weight and drag, have a high power-to-weight ratio, and fly as flat a course as possible without climbing and descending between pylons. At the Reno Air Races, the Unlimited chase airplane flown overhead by Hinton, or in the past, Hoover, calls out to the racer in trouble to climb because airspeed is like money in the bank: We can turn it into altitude, and the higher your altitude, the more options you have.

Unashamedly biased, I think the best example of EM is in an aerobatic sequence. An aerobatic routine isn't just a random set of maneuvers. Each maneuver must set up for at least three maneuvers ahead, making choreography a delicate balance between artistry and the use of available energy. The akro pilot manages airspeed, altitude, angle of attack and sequence of maneuvers, all in a limited amount of airspace.

People ask me if I change my air show routine from show to show. I tell them it's not that easy. My routine is carefully designed for optimum energy throughout the sequence, and each maneuver sets up for the next. Every maneuver ends either gaining or losing energy, so if I change the fundamental nature of one maneuver, then I have to change the next one and the one after that. I can add to a maneuver, such as a roll on a hammerhead, but if I change the hammerhead, which is an energy-gaining maneuver, into an Immelman, I'll end up going slow instead of fast. The next maneuver will then have to be one that requires very little speed instead of a lot of speed. Therefore, changing one maneuver in a sequence can fundamentally change the entire routine.

Good choreography makes good use of EM. A well-designed air show routine keeps the crowd interested because their eyes are always glued to the performer, watching for what's coming next. The flying stays show center, the maneuvers flow, and there's very little dead time. A poorly designed sequence has a lot of gaps and breaks, giving the crowd a reason to look away and lose interest.

Further, while the design and flow of a routine is important, a poorly performed maneuver can also dissipate energy. A good example is the snap or flick roll. The key to doing a good one is to make it clean, dissipating as little energy as possible. The technique for doing a snap roll is to pitch until the airplane stalls, unload the stick to accelerate the roll, simultaneously adding rudder to make the airplane rotate. If the pilot buries the stick too deep and doesn't unload it to accelerate the snap, the airspeed will bleed off rapidly, losing 30 knots or more instead of a more desirable 10. Adding unnecessary aileron also dissipates energy by displacing the maneuver, and moving it right or left. Even a "simple" hammerhead isn't so simple. For example, the pilot has to put the airplane in a vertical position, not two degrees positive or three degrees negative; the wings have to be level, not dropped to the right or left, and the pivot has to be at zero airspeed. If any of these things aren't just right, the airplane will give away valuable energy, and the next maneuver will be compromised. The Extra has a lot of power, and the airfoil is designed for maneuverability and the ability to turn corners at slow speeds, so I have a lot of latitude in designing my routines; not so for John Mohr in his stock 220 Stearman or Manfred Radius' Glider aerobatics (with ribbon cut)---two incredible masters of EM.

At our aerobatic school, Patty Wagstaff Aerobatic School at Southeast Aero in St. Augustine, Fla., we incorporate the finer points of airmanship into all of our aerobatic courses. I like to call it "finishing school." Pilots learn or are reminded that keeping the airplane in trim with the ball centered in a climb improves the climb rate, and they can watch the needle on the altimeter move a lot quicker.

I love the art of energy management in flying. It can take a lifetime to understand the finer points. It also makes me think how we humans are infinitely more complicated when it comes to learning our finer points as we aren't subject to the finite laws of physics that an inanimate object is. Only we have the ability to create energy. How do we manage energy in our lives? I'm of the same vintage as the 1959 V Tail Bonanza I fly. I'm sure it performs as well as it did the day it was born, but I'm not sure I can say the same for myself.

Wikipedia defines energy: "In physics, energy is a property of objects, transferable among them via fundamental interactions, which can be converted inform but not created or destroyed." Cannot be destroyed!

Unlike my Bonanza, our energy levels change over time, but we still have the ability to create it. The pendulum might swing; on one side we're drained by illusion, indulgence, resistance, anger, heaviness of spirit. On the other, light-ness, joy, creativity and forgiveness. It's only at the center of gravity, when life is in balance---just like an airplane---that we find balance, too. A well-centered airplane flies best; a well-centered person lives best. Energy is life, and healthy life is full of energy.

An airplane's energy is finite, but ours isn't. I lie in bed and feel my heart beating. Alive and vital, my life and energy is a self-propelled miracle. Perhaps we're the strongest machines of all because only we can create the energy to make things happen. EM is the most important thing we do as pilots, and maybe the most important thing we do for ourselves.