October 22, 2001

Discussion Of Boom And Zoom Tactics

by Andy Bush


Lesson One (October 22/01):  Defending Against The Boom and Zoom

You are presented with the following situation:  a typical "angles" fighter, such as a Spitfire, is bounced by a typical "energy" fighter, such as the P-38.  The attacker has the altitude advantage and is using a boom and zoom attack on you.  What should you do?

Response by Vince "Beer Camel" Putze, representing


  1. Fuel state of both aircraft is such that it will not influence the outcome. - The attacking aircraft does not end the engagement early, and the defender does not 'die' due to fuel starvation.

  2. Aircraft are of the same 'generation' in development. - It is not a later Mark Spitfire vs. an early model P-38.

  3. Aircrew capability is approximately equal.

  4. No additional threats for either aircraft. - In other words, the cavalry will not ride in to save the day.

  5. The engagement begins at 'medium' altitudes. The ground is not a factor initially

  6. Realistic individual priorities/objectives - Survival is the most important objective. This is not always the case in flight simulations; virtual life is cheap and plentiful.

  7. Both aircrew's primary mission objective is to survive, secondary is to kill the other. No complex strategic goals that would influence the 'Tactical' decision process.

This is written primarily from the point of view of the defensive fighter (Spitfire); however some offensive considerations will be discussed .The first thing is to identify the individual objectives of each combatant. As a generalization they are:


  1. Survive

  2. Obtain a quick kill, ideally unobserved

  3. Maintain tactical and energy advantage - avoid a sustained turning engagement.

  4. Separate prior to losing the offensive


  1. Survive

  2. Avoid the adversary weapon/weapon parameters

  3. Neutralize the positional / energy advantage of the P38

  4. Transition to the offensive by converting the engagement to a single circle turning fight.

Please notice that the option to separate is not included in the Spitfire's list. This is because it is not an option for him except in very specific circumstances. A persistent faster fighter will eventually run him down. Also note that the P-38 can terminate just about any time he wishes to! (Assuming he is not a total hamburger.remember.. a hamburger in any bun is still a hamburger!). So what is the Spitfire's best 'battle plan'? Well. It depends, but the general idea is to negate weapon threats by denying turning room while whittling away at your opponents energy advantage. Hopefully, he will make a mistake and allow you to take the offensive!

Initially lets assume both pilots see each other early, at long range. The Spitfire pilot will immediately realize the huge altitude delta. This is not good, regardless of what kind of fighter he is about to engage. Remember the 'objectives'. Survival, for the next few minutes, is relatively assured; So lets work on neutralizing the energy advantage. If his lateral separation is enough, the Spitfire pilot should put the bandit on his tail and accelerate away. He should gain as much energy (speed and altitude) as he can until the P-38 forces a defensive reaction. What happens next will also convey the intent of the P-38. If he turns hot on you, he is looking for a fight. If not, then he either doesn't see you or in not in the mood to play. This initial move will provide the Spitfire pilot with more time to assess the situation because the closure of the P-38 will be less in zero aspect geometry. It also gives the P-38 jock an opportunity to make his first mistake. If he ramps down too early in order to rapidly reduce range, he will be voluntarily giving up some of his total energy advantage (Fig.1). The Spitfire pilot should continue to work on energy but will eventually have to threat react.

Figure 1
Figure 1 The Bandit is seen early enough, with enough lateral separation, to allow the Spitfire some energy building room. The P-38, in this case, makes the mistake of committing too early and sacrifices much of his altitude advantage.

If the P-38's stick actuator does indeed make the mistake of diving down early, and he is approximately level with you, the 180 pitch back for a beak-to-beak gunshot is as good a plan as any (Fig 2). Be aware HE will have a shot on you too; it depends on how lucky you feel, how good your 'quick draw' shooting skills are, and how good he is. I guess a good way to sum it up is; the good news is you get to threaten him; the bad news is you are placing yourself in the P-38's weapons parameters. Just realize that this turn must be accomplished soon enough to give you time to turn, stabilize, aim and shoot. You have also just traded some amount airspeed for nose position. In this case the P-38 will still have a significant airspeed advantage (pronounced zoom capability), but he will have pissed away much of his altitude advantage.

Figure 2

Figure 2 Bandit ramps down too early and is co-altitude for his initial pass. You are confident enough in your shooting ability to go beak-to-beak. After the merge, extend for more energy; you will still have a relative energy deficit in most cases.

If you do not care to risk a nose-to-nose gun shot, and possible collision, then the 'standard' defensive break should be used. (Discussed in the next section). A word about energy management is relevant here. When you are extending away to build energy, your airspeed is probably above 'corner' velocity. When you decide to turn back, assuming the bandit does not immediately threaten you, climb to reduce your airspeed to corner (Bank energy.. convert airspeed to altitude). Do not give it away by pulling the throttle to idle. When you turn back in, vary your lift vector (Probably Down!) in order to maintain corner velocity. Obviously, if you mistimed this, and the P-38 is a threat (not yet to gun range, but getting there fast) you must put your lift vector directly on the bandit and pull. This leads to the inevitable 'guns jink' unless you force the P-38 into lag or he comes off and zooms to maintain energy. More on this later.

Let's now assume our adversary is more proficient. He turns hot, maintains his altitude and speed, and he is closing on you. This also includes times when you get a late tallyho and you find an unexpected bandit already high above you. At some point he will tip in and commit, that's when you have to think fast and react to him. The exact geometry of this engagement will vary slightly depending on when the P-38 rolls in, but basically it looks like this:

Figure 3

Figure 4

The P-38 has just rolled in on us .. what now? The idea of bending it around in order to meet 180 degrees out and shoot him in the lips is valid, BUT the P-38's energy advantage and the geometry of his attack have to be considered. If a hard turn around in order to shoot leaves you nose high, out of airspeed and ideas.. Well . unless you kill him. you have just converted yourself into an expensive strafe rag! Realize that this turn is not going to give you much time to aim, so it is a relatively low PK shot. Conversely, if you are going to meet 180 out, the P-38 driver has a much longer 'settling' time in order to refine his aim and shoot! If I were in the P-38 and I saw the Spitfire nose high and slow after attempting this, I would Turn on him as he was in his slow speed (or out of control) recovery and gun him. At slow speed you are very vulnerable. A more conservative plan would be to follow our original strategy and deny the P-38 a shot while equalizing the energy delta.

This is where we are going to use some of our energy to stay alive. (Remember the old adage that speed is life!) We have to react to the imminent threat of getting gunned. Our threat reaction has to begin prior to the P-38 weapon solution, and be a Break turn. Ideally, just before the bandit reaches our turn circle we place our lift vector on him, pull, and generate as many angles as possible without sacrificing your entire bag of knots (As close to corner velocity as possible). The objective is to avoid providing a shot opportunity to the bandit by causing him too many angles to even attempt a shot (Fig 3). If the P-38 begins to align for a shot, transition to an 'out of plane' maneuver, in this case it is almost Always toward the ground. This will be the classic 'guns jink'. As soon as the threat is negated.. SAVE/GAIN ENERGY! The exact maneuver is dependant on the geometry of the attack, but the basics are the same.

Figure 3 Defeat the attack then continue to whittle away at the P-38's energy advantage

We have just survived the first pass. Ok, now what? Wait until he has begun his zoom, and then continue your energy gathering. Place him on your tail again and gain as much separation/altitude as you can (By the way DO NOT GET SLOW!! you need maneuvering speed to avoid lead poisoning. If you DO get slow.. Trade altitude for airspeed!).. Continue these 'lines' (acceleration away for energy) and 'Hooks' (break turns to avoid getting shot) until you equalize the relative energy states. Most of the time these fights will be a descending event. This has real life (or multi bogey) implications. If he stays on you, he risks attracting some of your friends to the fight, while liquidating his altitude 'bank'. When you do get to ground level he now has lost the space to maneuver below you . He also now has the additional threat of the ground.but you do TOO! Be careful! Ok .. We have worked our way to a fairly equal energy situation through superior airmanship and cunning..Now what?

If it is our lucky day, and we are wrapped up with the USDA Grade A hamburger who now decides to turns with us. Great! Once he gets into our 'phone booth' it is DAMN hard to separate. Attempt to force a single circle fight, keep pressure on him, and you should be able to gun him in a few turns, If you do not continue to threaten him he will have the ability to build some smash and possibly separate.. be alert for his attempt to do so. It is another shot opportunity if he buffoons a separation maneuver.

The good P-38 pilot would probably decide that you are just too hard to kill today and go home. . Or he may be just extending in order to re-acquire his energy advantage (Remember his objectives!). If he does appear to be leaving, maintain the tallyho and BUILD AS MUCH energy as you can while not being threatened. If Mr. P-38 does re-attack you will be ready for it.

The next mistake the P-38 is likely to make is continuing to fight an energy fight without enough energy. This exact point is excruciatingly hard to accurately determine in most cases. This where experience pays off. When you determine you are co-energy , and the geometry is favorable, attempt to reverse on him and go counter offensive. If you assessed the situation correctly you should be offensive.if not you have just played your wild card and your bag of knots. Depending on his energy vs. your energy all you may have is a fleeting shot as he attempts to separate at tree top level ready to shoot. A few well-placed hits will cause him to react and quite possible become anchored in a low altitude, co-energy fight with a superior turning aircraft. All things being equal he will not / should not survive that. Another outcome of an early reversal is a scissors. Not a bad thing in this case since we have the superior turning (most likely slower flying) airplane.

Figure 4 When the time is right!.... Reverse and GUN the Freak! This is where you can end up in a vertical scissors. A race to see who can fly the 'slowest' faster! Be good at departure recovery!

Well, that is the short version of a very complicated and dynamic BFM problem. Patience is more than a virtue in this engagement.. It's required! If you get greedy and try to end this contest too quickly you will most likely die. Be patient.. it's just like eating an elephant single-handedly .. take a bite, chew well, swallow, and repeat process until complete!

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