Most head-to-head dogfights are won or lost in the first 15-30 seconds. Pilots who learn how to exploit this critical period to their advantage will persevere, and those who do not will perspire. The discussion in this section assumes that the opposing aircraft are infinitely aware of one another (there is no element of surprise), and that both aircraft begin on relatively equal footing, without any positional advantage. The clearest way to depict this is via a hypothetical meeting engagement, where the two aircraft are in each others' forward hemisphere at roughly the same altitude with minimum lateral separation when the engagement begins.
Aggressive pilots might continue forward from this position to complete the head-to-head pass prior to subsequent maneuvering, but this certainly isn't the only tactical option in this situation. Before discussing those other options, however, you must keep in mind that the final objective of any series of maneuvers is to gain the angle/position to put ordnance on target. And this objective does not change regardless of the type of plane you are piloting, an "angle" fighter (better turning capability) like the Spitfire or an "energy" fighter (better speed, climbing and diving capability) like the FW-190. But the type of plane you are piloting does affect the choices of maneuvers which will accomplish that goal in the most efficient, and least risky, manner.
For example, the angle fighter in this scenario should break first, well before the two aircraft get into gunnery range. We will assume a left break of 45 degrees for this example, but you can reverse the direction and use the mirror of the tactics discussed herein equally well. Keep your nose down slightly as you do this break turn to retain some additional energy. Additionally, the vertical separation you establish below the enemy allows you to pull up towards him to gain yet another angles advantage.
Most opponents will bank slightly right at this point hoping to get into a nose-to-tail pursuit path of you. You are more aggressive than they anticipate, however, and once you have completed the 45 degree break to gain some lateral separation, you roll your aircraft 180 degrees and pull back on the stick hard to reverse towards them. You have bled some speed in the process and now have a much smaller turning radius than they do, which equates directly to an angles advantage even if you are still in something close to a nose-to-nose configuration when you come out of the reversal. They cannot adjust their gun angle swiftly and you can, so this is your first opportunity for a snapshot to rake the target.
At this point in the engagement, if they choose to break left you are already in a position to cut off their turn and enter into a scissors if need be from a position of advantage. If they break right into you, do another reversal and stay below their flight path. You want to be coming up from below if possible at each firing opportunity to minimize your own exposure.
If he chooses to go high, which is his best tactical choice because he is in a higher energy state due to his speed, pull up gently into an oblique climbing turn inside his vertical arc. This is a Chandelle Turn (see Glossary) and it is very energy efficient. He will generally be pulling up hard (especially if you just took a snapshot at him), taking more g's and bleeding speed more rapidly than you are, even though you began this phase of the engagement in a lower state. You don't need to keep up with him in this maneuver, just keep a lead pursuit angle on him with your guns. If he has a sufficiently high energy state, he could choose to climb and extend at this point and you won't be in much of a position to stop him, but most pilots will try to turn back to reacquire you out of their blind spot instead. When they do, you are in the perfect position for a deliberate tracking shot with very low deflection.
Another approach for the Angles fighter against an opponent who goes vertical is to use an early Immelmann to reverse direction inside that opponent after the merge and enter into a vertical rolling scissors. Be forewarned, however, if you don't succeed in getting a guns kill in the first couple of passes during the vertical scissors, do a wing over and extend to regain energy and come back from a better position.
For an Energy fighter beginning in the same tactical situation, the approach is quite different. Instead of breaking in lieu of a head to head pass, the Energy fighter should begin his most energy efficient climb almost immediately after sighting the enemy to increase vertical separation and store up as much of it's most capable quality before the engagement proper begins. And for the remainder of the tactics we will discuss, the following axiom is of greatest importance to the pilot of an Energy fighter: BE PATIENT! The Angle fighter need only "yank and bank" to create firing opportunities at slow speeds. When you are at high speed, these firing windows are very small. Conversely, however, you need to spend a lot more effort setting up a firing opportunity based on maneuver and energy advantage, then make a speed bleeding stick correction at the very last instant if needed to bring the rounds on target.
OK, back to the example. You've begun to climb and are hoping that the enemy will try to climb with you, bleeding speed as he does. Because you are climbing first, you need to ensure that you begin your climb early enough to stay outside his gun range. Your next step is to perform a very high, low-g loop to come over the top without bleeding too much speed and begin your attack proper on the downward stroke of the loop. Alternately, if you have a really high energy advantage over the enemy, you can do an Immelmann turn then dive back. A defender with slow speed will be unable to duplicate either maneuver, giving you complete freedom of engagement and initiative in the vertical plane. And if the bandit tries to dive down in a defensive spiral to regain energy, you are already in position to follow him down. Just be careful not to overshoot and have the tables turned on you.
The key if you have a sufficient energy advantage at the beginning of the combat is to maintain that throughout the engagement to keep the fight on your terms. If you are impatient to set up a shot, you will begin pulling higher g turns to try and get a quick guns solution. Unless you are successful, you are bleeding energy and sacrificing more of your advantage to the defender with each turn. Without a distinct energy advantage, the better turning aircraft (i.e.: the Angles Fighter) is favored to win the engagement.
All of this sounds good in theory, but to put it in practice you must be intimate with the capabilities of your own aircraft and also those of the bandit you are engaging. And remember, these capabilities vary based upon where each aircraft is operating in its flight envelope. Further, when you are merging with an enemy, you only have a few seconds to properly identify that enemy and assess his energy state. Based on these factors, you alone must judge whether or not to pursue an angle or energy based strategy for the ensuing engagement. Also, when it is appropriate to shift between the two approaches or break off and extend to attempt to regain a lost advantage.
Here are some good lessons learned pertinent to this decision making process:
1. Never attack when you are outnumbered unless you possess a distinct energy advantage that can also be used to extend safely after the attack.
2. It is never a good idea to initiate an engagement against a target which has a lot of altitude advantage which can quickly be converted to a speed advantage. Climbing into a fight with an energy disadvantage gets you killed.
3. Don't waste an energy advantage with poor follow up maneuvers. If you've just completed a high closure rate gun pass, convert your kinetic energy back into potential energy by pulling up in an oblique Immelmann, Chandelle Turn or some other energy efficient maneuver to set up another pass. Don't try to pull around quickly in a flat turn to reacquire your target or worse, go low to set up for the next pass. In the latter case you are retaining kinetic energy but your turning radius at high speed will be excessive and you will still have to climb back up after the bandit. A smart adversary will cut off your pursuit curve if you go low and quickly turn the tables on you.
4. Unless you are pursuing a pure energy strategy with a distinct energy advantage to begin with, turn into any impending attack to maximize the deflection rate of the shot.
5. Use lead turns whenever you have an equal or inferior energy state to cut off the enemy in every plane of engagement, horizontal, vertical or oblique.
6. When you have a superior energy state and are approaching a gun solution from astern, if the target reverses and breaks low with a Split-S to build their energy state, you are better off following with a lag pursuit or breaking off and gaining a higher altitude advantage than attempting to follow them with the same maneuver. If you do, the additional speed advantage you had will translate to a wider turning radius in the Split-S and you will actually end up at a lower altitude and worsened energy state than your intended kill.
7. Even the best Angles fighter loses much of its maneuvering capability at very low speeds. Wear these fighters down by making multiple high energy passes at them, forcing them to yank and bank to try and return fire. If you are patient enough and they are not smart enough to recognize the precariousness of a deteriorating energy position and extend to escape, you will wear them down to the point that they are an easy kill. In addition, they will learn that position/angle is relatively worthless against a much faster target whose deflection is so high that your chances of hitting it approach zero.
8. When you've been forced onto the defensive, don't maneuver in a single plane, either vertical or horizontal. You are in a 3-D environment. The more of it you use, the more difficult a target you are. Jink. Use all of the control surfaces on your aircraft to bob and weave like a prize fighter.
9. If you have the energy advantage, don't get sucked into maneuvering for a stern shot in a flat scissors. You will overshoot. The slower aircraft with better turning capability wins the flat scissors.
10. Both the rolling and vertical scissors maneuvers are won by the pilot who practices the best energy management. This is because these maneuvers require a constant tradeoff between energy and angle until one of the contenders completes a gun solution or both pilots disengage. The better you control your speed vs. your load factor to achieve sustained maximum turning performance, the greater the advantage you have in either of these maneuvers.