The concept of Energy is fundamental to air combat and requires more than a cursory study. Understanding Energy is not complicated but keeping a close tab on your energy state, as well as the energy state of all aircraft around you including those beyond visual range, is extremely complex – because the energy situation changes constantly with the multitudes of moves and vectors and positions involved in the overall air combat equation.
In short, Energy is the sum of your position and airspeed. You create energy by cranking up the engine and by stashing its output in a combination of speed and altitude. This is a simplistic approach though, for you must also compare your energy with that of the enemy’s. In simple terms, a fighter which travels 10 ft off the ground at maximum speed has less energy than a similar fighter that travels 1,000 ft off the ground at maximum speed – because the high fighter can convert his altitude to an overhead of speed beyond that what the low fighter can produce.
In other words, you can improve your Energy situation considerably by using Time (spent on climbing) in converting your present energy to potential energy. This potential energy can be spent at a later time, by diving. By stashing up on altitude even the slowest aircraft can dominate the fastest aircraft, at least for a while – until the energy difference is levelled.
Energy and Vectors
There is more to Energy than Speed and Altitude however. You must also consider the vectors involved in a combat. Consider two equally performing fighters heading directly toward each other at maximum speed and at the same level. Before they meet (merge) their energy levels are equal – the fighters are neutral. Shortly after they merge however, fighter A hauls around to follow fighter B in order to park on his six o’clock. In so doing he must spend some of his energy, for drastic manouevres incur a drag penalty that reduces airspeed. Fighter B however has no intention of fighting – he keeps going on his original heading without giving up an ounce of energy. Fighter A is now wallowing out of guns range far behind fighter B and must spend some time in recouping max level airspeed. In the interval fighter B motors on and leaves fighter A in the dust.
You will probably hear seasoned pilots telling you to “keep your energy state high”, but what does it really mean? Heck, you are already flying with the hamsters on max – how can you go any faster?
What the veterans are telling you is to fly higher and to avoid largely stationary turning contests, especially in a high-threat area. When the unknowns are massive you need to have an overhead of energy for emergencies. In short, as you will no doubt have experienced already, you will not want to be found low and slow in an area where bandits are coming in high and hot. These same bandits have the opportunity to make rapid and devastating attacks on you that you have little chance of defending against – because the attacks develop in the blink of an eye and can come in from any direction. If you, on the other hand, are flying high and fast, you can safely disregard everything that is lower and slower and thus choose your victims at leisure.
You may have heard of “energy” and “angles” fighters, commonly referred to as “B&Z’ers” (Boom and Zoom) and “T&B’ers” (Turn and Burn). As the monikers suggest, there is a vast difference between the two approaches to air combat. The B&Z fighter flies high and fast; he only turns when there is no one to interrupt his reversal; he engages in long slashing attacks and he will make himself scarce the moment he loses positional and/or energy advantage. The T&B fighter usually flies and fights on the deck; he likes to haul back on the stick; he prefers to stay close to his opponent in tight turns and loops; he will fight to the death for should he lose positional advantage there is anyway little chance of escape. Still, the B&Z and T&B fighter both employ energy in the fight – it is merely a question of scale.
Energy up close and personal
When you are engaged in a max-rate turning fight, energy is most tangible. Consider two equally performing fighters turning nose to tail in a flat circle on the deck: if their energy state is neutral, neither will earn angles on the other and they will remain locked in a flat turning contest until one of them makes a critical mistake (such as pulling too hard and stalling momentarily, thereby losing energy and position) or decides to leave the static circle.
If, on the other hand, one of the fighters relax stick pressure to build up speed for a few seconds, the opponent will most likely continue his max-rate turn and cut across the circle to gain a guns solution. At that point the former fighter is becoming energy-rich but angles-poor, while the tailing fighter is energy-poor but angles-rich. The outcome of this example fight is by no means certain: the energy-rich but angles-poor fighter may yet use his recouped energy to turn the table on the energy-poor but angles-rich fighter on his tail.
You will also find it easy to keep tabs on the relative energy states by thinking in terms of “level” “uphill” and “downhill”. What you absolutely must remember is that energy is what allows you to (or disallows you from) performing combat manoeuvres. If you are out of energy, you are powerless: you cannot turn, you cannot climb, you cannot evade an attack – you will shortly find yourself in a burning wingless wreck. If you have an overhead of energy you are free to dictate the fight; you are free to attack or disengage.
Fight with your brains, not with your brawn!