SimHQ.com - Air Combat Zone - It's All a Matter of Perspective, Part Four

In Part Three, we looked at a number of concepts and techniques. The article finished with a discussion of how to relate these concepts to a conventional rear aspect attack. I’ll end this series with a final discussion of how these tips and concepts can be employed in a front aspect attack as well as pass along a few ideas regarding defensive BFM in a typical air combat simulation.

To briefly recap the main point in Part Three, we learned that BFM is an exercise in fuselage alignment and the control of closure. The same is true of front aspect and defensive BFM. For our purposes in this article, our objective in front aspect BFM is to maneuver to gain a position aft of the target’s 3/9 line. To do this, we will have to turn our fuselage axis around as much as 180 degrees as we maneuver to the target’s six. This will require a certain expenditure of energy on our part...while it may be a wonderful thing to successfully end up at your target’s six, it will do you no good if the target then escapes your well flown attack simply because you ended up out of airspeed and ideas at the same time!!

We’ll try to minimize the chance of this happening by stressing the relationship of the horizon to your choice of maneuver direction. Not only will you see how to get turned around but you will gain an appreciation of how to conserve energy at the same time.

We will then apply the same thinking to how to defend against an attack when the bandit is behind our wingline. Again, our objective is to control fuselage alignment and closure, but now the shoe is on the other foot! When on the defense, fuselage mis-alignment is often the desired result, and negative closure in the form of an extension or separation will keep you in one piece for the next fight!

As before, I will illustrate these ideas using diagrams and screenshots of padlock and external views. Remember, our objective here is to help you fly better BFM. The academic content of these articles may make you a bit smarter as far as BFM technicalities go, but I want to improve your flying...and I know you do also. In the real fighter world, a skilled pilot is often referred to as "having good hands". That’s my goal for you...good hands...so let’s get to it!!

Basic Concepts

Fortunately, most of the important BFM academics have already been discussed. If you are a new reader and have not read Parts One through Three, then please do so before you attempt this final article. I will assume that, by reading past this point, you understand and are familiar with the BFM concepts contained in those previous articles.

When we talk front aspect BFM, we must include several additional BFM concepts that were not significant in our discussion of rear aspect offense. These include lead turns, lateral separation requirements, and the concept of the one circle/two circle fight. In addition, because of its very important relationship to energy levels, we will again include the horizon in our examination of how to use both the padlock and external view to engage a target "beak to beak".

1. Lead Turns.
In the world of BFM, lead turns are like cleanliness...next to Godliness!! Nothing marks a pilot as a skilled practitioner of BFM so much as a well flown lead turn. I’ll even go out on a limb and say that if a pilot could only do one thing really well, then, as long as that one thing was a lead turn, he has a leg up on anyone he comes across. So much for the preachin’...how about a definition, for starters?

Lead Turn - the act of aligning your fuselage axis with your target before it does the same to you. The emphasis here is on the significance of timing in the maneuver. You are maneuvering your aircraft relative to the target’s fuselage axis before it begins a maneuver against your fuselage axis.

The most common reference to the lead turn is when the maneuver is flown from a front aspect situation. In this case, you begin your turn into the target before you pass its 3/9 line. The assumption is that the target does not attempt to counter your maneuver. By turning before you pass the target’s 3/9 line, you are turning early...in fact, some references use the term "early turn"rather than "lead turn".

While the lead turn is most often described in a frontal aspect situation, this is not the only time the maneuver can be flown. Lead turns are often the key to success in a scissors, for example. The point to remember is that good things can happen when you beat your opponent to the draw when it comes to aligning fuselages.

2. Lateral Separation.
When we talk lateral separation, we are always thinking of turning room...either trying to get it (in an offensive sense) or denying it (when on the defensive). We usually visualize our turning room needs by referencing the target’s wingline and fuselage axis. We maneuver to maximize or minimize the distance from the target’s fuselage axis as measured along its wingline.

For frontal aspect situations, your attempt to gain lateral separation is usually the result of your desire to lead turn the target. The lateral separation will give you the turning room needed to minimize the possibility of overshooting the target’s flight path.

A defender, on the other hand, often is attempting to reduce or eliminate turning room. The usual objective is to cause the attacker to overshoot or need excessive maneuvering to regain a threatening position thereby allowing the defender to gain separation.

3. One Circle/Two Circle Fights.
Many of the manuals that come with today’s sims describe a variety of maneuvers and tactics. To varying degrees, these descriptions are technically correct...but what is missing is relevant info on how you can fly the maneuver given the viewing system of the sim. Too often, the maneuver or tactic requires a level of SA that the viewing system simply cannot provide. This is particularly true in the case if the one circle/two circle option.

This option occurs when the attacker meets his target head on...often called "nose to nose", or in fighter pilot slang, "beak to beak". For purposes of this discussion, we assume the target will always turn into the attacker. The attacker has the option of turning into the target...this is the more conventional of the two techniques and allows the attacker to maintain a tally on the target. In this option, the attacker and target fly separate turn circles, as a result this option is called the two circle fight.

The attacker has a second option. At the merge...the point where each aircraft passes each other’s 3/9 line...the attacker can turn away from the target. Called the one circle fight, this technique has the advantage of reducing maneuvering time but almost always results in the attacker losing sight, at least initially, with the target.

It is this loss of sight that makes the one circle option less workable in a flight sim. Some padlocks only "work" if the target is considered visible...if the sim’s padlock programming determines that the pilot cannot "see" the target in a given situation, then the padlock view will not be available until the sim’s AI decides the target is again in visual range and angular limits. For this reason, the external view is superior when flying a one circle fight...but not all sims offer an external player-to-target view.

Lastly, the one circle option is a bit higher up the ladder in complexity. Because of this, most sim pilots will opt out for the two circle fight. For many pilots, it just feels more comfortable.

4. The Horizon Line.
Once again we return to the relationship of the horizon to the maneuvering situation between you and your target. We’ve gone over this several times before, but I’ll touch upon it one more time. How you use the effect of gravity in your BFM can spell success or failure. Your use of God’s G can favorably or unfavorably impact your energy state. In this article, I’ll point out some tips on how you can use gravity to gain or maintain your competitive edge. Well, so much for the academics...let’s strap on our flying machines and go to work!!

Offensive BFM - Nose To Nose With Your Target - The Frontal Aspect

Well, here you are...beak to beak with the bandit...how did you get into this situation in the first place? For our sim flying, I see three typical reasons why. The first and perhaps most common reason, and the one situation that you will encounter in almost any sim, is that the sim’s "Instant Action"or "Quick Combat"scenario starts you off nose to nose at some given distance. Or it may be that you have selected this relationship on the sim’s set up page...no matter. A front aspect situation is common to all sim scenarios and is one you want to be proficient with.

The second possibility is that you have deliberately maneuvered to this position. This can often be the result of H2H or multi-player scenarios where you and your opponent take the shortest distance between two points to engage each other...in this case, this results in a face to face situation.

Lastly, you can end up with a front aspect engagement as the result of a swirling, multi-player scenario. In these circumstances, many pilots opt out for staying fast and engaging only those targets that they meet in the front quarter ( front quarter - plus or minus 45 degrees off your nose). These situations are known as "targets of opportunity" set ups...they are unpredictable, occur with little advance warning, and require immediate decision making on your part. Your "opportunity' in this instance is fleeting...your success or lack thereof is going to depend on your ability to choose a course of action that keeps the bandit out front and you behind...as it should be...so let’s get down to specifics. As in the previous discussions, I’ll recommend a few tips that you may find helpful in dealing with a front aspect threat. Because a lead turn is the maneuver of choice in beak to beak passes, most of these tips deal with specifics relating to performing lead turns.

Tip #1.
If at all possible, your first job is to get the lateral separation necessary for a good lead turn. In a perfect world, this separation will be exactly what is needed for you to roll out in the target’s six. The distance will be double your turn radius as determined by your entry airspeed and "g" pulled in the turn.

But the world is seldom perfect, as we all know. If you are flying a jet sim, double your turn radius works out to be around 6000 -9000 feet. For the typical set up, you will seldom see this amount of separation unless the target simply is unaware of your position and gives you the time to maneuver that far out on his wingline. Fat chance!!

Instead, you will most likely get one shot at a hard turn away from the target to go for some lateral separation...then you are going to have to roll back into the target to watch it. The following picture shows approximate lead turn initiation points that you can use in any forward view.

Here’s an idea. This separation does not always have to be measured along the wingline...in fact, you can visualize this distance as an approximate circle drawn around your nose...the center of your HUD. If you can maneuver your plane such that the target approaches any edge of that circle, you can then turn towards the target to align yourself with the target. For you engineer types out there, consider this circle to be the locus of points for the initiation of a lead turn!!

Depending on your energy state, you may find certain advantages in flying below the target’s flight path as you look for your turn entry point. This descent below the target may increase your energy level and may make it more difficult for the target to visually keep you in sight...in fact, because the target will be looking down through its fuselage, its padlock view may be adversely affected.

In this instance, you will be faced with an upwards turn towards the target...a nose high lead turn. The target, if it responds to your lead turn, must turn down and towards you. This will tend to accelerate the target and thereby increase its turn radius. You, on the other hand, will have God’s G to help you shorten your effective turn radius. While each situation is different, one technique is to pull down and away from the target on about a 45 degree angle below its wingline. This will result in your pull up being a pitchback initially, rather than a loop. This maneuver is less demanding on your energy state and is easier to fly with regard to the horizon.

Here’s a nose low lead turn seen from the external view. Note that the turn is again begun before passing the target’s wingline, and your lift vector is oriented below the target’s flight path.

Tip #2.
As you initially turn away to establish separation, make your turns hard and quick. Rotate your lift vector to the direction you want to go and then pull hard to move the nose the desired amount. Then, relax g and roll back to reacquire the target. Minimize the time that you have your belly up to the target. You can improve your SA by flying this maneuver in external since the angular relationship of your fuselage axis relative to the target’s will be more evident than it would be if you were using padlock.

Tip #3.
Visualize your lead turn point using angles off your nose. As a technique, allow the target to fly to a point about 20 - 45 degrees off your nose as it approaches you. For many sims, if you are passing directly abeam and level with the target, this is an area between the outside edge of the HUD/gunsight and the rounded canopy frame or edge of the monitor screen when you are using the forward view. Obviously, you do not want to wait until the target is past your wingline...or you past its wingline. Another way to view this is to imagine a line from the target’s nose that is about half way from its wingline to its nose...as you cross that line, begin your lead turn.

Tip #4.
Now, let’s talk energy! As you plan your lead turn, bring the horizon into your crosscheck. Remember the high wing/low wing analogy from previous articles. If your smash (energy level) is high, then orient your lift vector above the target’s flight path...if you need to conserve your energy, then roll to point your lift vector below the target’s flight path before you turn. Your turn radius will vary slightly in size depending on which option you choose, but the effect on your energy state will be more important to you in the long run. Let’s look at this situation using a padlock and forward view.

Figure 10 - Lead Turn - Nose Low - Padlock.

Figure 11 - Lead Turn - Nose Low - Forward View.

In the next picture, the padlock guidance is directing a roll to the right. Here is an excellent example where I would disregard the sim’s AI and fly my jet the way I want to fly it...in this case, I would continue my pull into and below the target’s flight path. Don’t ever expect the sim’s AI to be 100% correct!

Tip #5.
Include environmental conditions in your maneuvering plan. If possible, get your turn displacement separation on the sun side of the target’s flight path...then, when you turn back into the target, the target will have to look into the sun to see you. Consider the background color of the sky and ground. Try to fly towards the darker of the two...this will make it tougher for the target to keep you in sight. Avoid "skylighting" yourself against clouds or sky if you can.

Tip #6.
I recommend you fly your lead turns in padlock or external. In any case, watch the target’s response to your lead turn. It probably will turn into you. Be ready to immediately BFM the target’s response. Remember the concept of "flying to the elbow". Use split-plane maneuvering to conserve your energy and turning room. Continue to maneuver to the target’s extended six.

Tip #7.
Planning a two-circle entry? This is the most commonly flown merge plan. If so, you will need some separation prior to the initiation of your lead turn.

Tip #8.
Or are you going for a one circle fight? Your entry to the merge is much different for this tactic. You DO NOT lead turn as a rule. You DO NOT want any lateral separation at the merge. You want to maximize you ability to turn inside the target’s turn circle. To do this, fly right at the target to minimize spacing. One technique is to fly slightly high so that you are slicing down and back into the target...this orientation takes advantage of the effect of gravity on your turn radius and energy state as you turn hard back towards the target. Wait until the target passes your 3/9 line before you turn...this helps assure the target remains out in front of your wingline as you come around in your reversal. In the next figure, the F-15’s initial one circle turn started out pretty much level. But then the Su-27 started a vertical move. The F-15 continues its one circle turn, but counters the target’s reaction by canting the plane of the turn into the vertical. In the turn back to the Su-27, the F-15 is thinking "high six...fly to the elbow"!!

Tip #9.
When should you consider the one circle option? As a rule, ONLY when you are flying a superior turning aircraft. Otherwise you run the risk of having the target out turn you and forcing you into a defensive position.

Tip # 10.
Anticipate the need for a low yo-yo to regain closure if you have elected to fly a two circle fight. As you come around in your turn, keep your lift vector on or in front of the target until you can analyze your relative energy state. If your closure is high, then fly to the elbow. If not, then pull your nose to a point in front of and below the target. Then unload (relax g) and accelerate.

Tip #11.
Lastly, we’ll return to the initial set up. Are you confused about what to do? Unsure of which plan to implement? Totally clueless? Don’t feel bad...we’ve all been there before. Point at the bad guy. Reduce your separation to a minimum. Go full power and blow through. Extend out for separation while rolling unloaded to keep the target in sight. Then reassess your position and opportunities...re-engage if appropriate.

These tips are not the "be all to end all" of head-on BFM. But they are a good starting point. And they all are usable given the viewing systems of a typical sim. Give them a try...experiment a little...find out which are good for you...and which are not. Then bring on the bad guys!! In the next section, we’ll spend the remaining time on defensive considerations.

Defensive BFM - Bandit Behind Your Wingline.

Congratulations!! You have neatly trapped the bandit at your six...now what do you do? First of all, all is not lost! You do have some options. A little skill and cunning on your part and you can turn the table on the bandit...but one thing is for certain. You won’t be able to defend yourself if you lose sight of the bandit...so the first and most important thing for you to master is to use your views to keep the bandit in sight. Do this with either padlock or external.

When the bandit is behind your wingline, he is trying to get into his weapon engagement zone (WEZ) for whatever weapon he is using. Your objective is to keep him out of this WEZ. You do this two ways...either gain enough separation to get out of the weapons range limitations or rotate your fuselage axis to generate too much angle off for the bandit to handle.

I’m going to offer some tips for you to consider. Use these tips and techniques to achieve one of three goals:

1. Goal #1.
Cause the bandit to overshoot or reposition by rotating your fuselage axis faster than he can rotate his...this is a fancy way of saying "turn tighter than him", but it underscores the central theme of these articles...control of your fuselage axis.

2. Goal #2.
Stagnate the bandit outside of his WEZ. Do this by controlling your closure (actually, in effect, you are really controlling HIS closure) to keep him at arm’s length.

3. Goal #3.
Lastly, and again with closure in mind, force a 3/9 overshoot. Simply speaking, make the bandit fly past you.

To make these goals, you have a limited number of maneuver options. These are kick turns, hard turns, break turns, and unloaded accelerations.

A kick turn is a hard turn (5-7 g’s) of short duration. It is used to move the bandit out of your deep six. A kick turn lasts one to two seconds and usually moves the bandit out to your 5 or 7 o’clock position.

A hard turn is an energy conserving turn flown at less than max g. It is typically a sustained turn (as opposed to a kick turn) and is intended to keep the bandit in sight while denying him the ability to close.

A break turn is a last ditch defensive move designed to sacrifice energy and nose position in order to stay alive. It is flown at max g and max power. It is flown out of the bandit’s plane of maneuver for a gun attack, and, for a missile attack, in the plane of maneuver of the missile. NOTE: For a gun attack, you BFM the bandit...for a missile attack, you BFM the missile!!

An unloaded acceleration is an attempt to maximize energy gain. Do this by relaxing your stick pressure to less than one g. Bank angle is not important. Use your HUD g reading if available to hold the unloaded g.

OK!! We’ve got our goals...we’ve reviewed our maneuver options...let’s get to those tips that are going to hopefully save your bacon!! In the following discussion, we’ll use the padlock and external views to visualize the important points.

Tip #1.
Recognize your cone of vulnerability. Right off the bat I’m throwing a toughie at you. Remember the depth perception problem I mentioned in the previous article? Well, it’s alive and well as we try to defend ourselves using our two views. It’s tough to judge the bandit’s range as you look to your six. Some padlock views include bandit range...externals often don’t. A rough rule of thumb...if you can recognize the bandit’s type of aircraft, you are vulnerable. If the bandit is still just a little dark "spot", then it may not yet have entered your cone of vulnerability...but sims differ in this regard. There is no easy answer to this inherent problem in our sims.

Tip #2.
Rule Of Opposites. This applies to your BFM with the bandit behind your wingline. He’s coming on like gangbusters, and you’re doing the chicken like nobody’s business. It may be a gross generalization, but keep this in mind. If the bandit goes up, you go down. If the bandit pulls down into you, you pull up into him. Saying it another way, if the bandit goes nose off of you, unload and extend. If he tries to get his nose back on you, then turn hard into him to take away his turning room.

Tip #3.
Turn only to increase aspect. Aspect in this case is the position of the bandit off your tail. Your defense should be a series of hard turns and unloaded extensions. Be careful of flying in a bank as you watch the bandit. In doing so, you often inadvertently have g on your aircraft...this causes you to turn, and this allows the bandit to close on you. When the bandit cuts across your turn circle in this manner, he is arcing you. This possibility exists anytime you have your lift vector pointed in the bandit’s direction. Don’t let the bandit arc you.

Tip #4.
Know the bandit’s gun envelope. The path of the bandit’s bullets approximates his gun line. You can visualize this gun line as a vertical plane extending out from his nose and down. It is lined up with his rudder (his lift vector). For this reason, maneuver towards his wingtips and away from his lift vector. Do this by rolling your lift vector in the direction of his wingtip (usually the low one for energy considerations) and pull. Remember that the bandit must be in lead pursuit for him to have a valid gun shot. Most sims are programmed more or less correctly for this gun parameter. If you are looking straight down his nose, he is in pure pursuit and may not have a valid gun solution. Look for his belly. If you can see the bottom of his fuselage, then he is in lead pursuit, and it is time for you to do some serious defense!!

Tip #5.
Know how to do a Gun Jink. A gun jink is a series of random hard turns of short duration intended only to do one thing...spoil the bandit’s gun shot. A gun jink will seldom overshoot the bandit, and it won’t present him with any insurmountable closure problems either. But it may keep you alive for a few more moments. Who knows? Maybe he’ll run out of bullets!! Seriously, do your gun jink as described in Tip #4. Roll towards the bandit’s wingtip. Then pull hard for several seconds. Watch the bandit. If he repositions nose off, then unload and extend. If he continues to move his nose forward in your plane of motion, then roll away from his gun line and repeat the maneuver. Don’t be a wussie!! Never give up and don’t just blindly pull on the pole. Fly smart and do your best. You are not always going to be successful, but give it your best shot...unfortunately, so may the bandit! Curses, foiled again!!

Tip #6.
Have a Lost Tally plan. A lost tally plan is nice to have in your pocket for those times when the world has gone to deep doo-doo and you don’t have a clue. We’re talking here about a situation where your counter-maneuvering has resulted in you losing visual contact with the bandit...typically this happens in a guns defense. You whip a world class gun jink on the bandit...then, you take a quick peek at the forward view to check your nose position...everything is OK so you switch back to your former view and...no bandit!! Where did he go? The answer may lie in your last maneuver.

We begin with the assumption that your gun jink or gun break was successful. This means that the bandit was forced to reposition to avoid a flight path overshoot or 3/9 line reversal. You now have to ask yourself...’Where would he most likely go?’. Quite often, the answer is up...the bandit is rotating his nose out of your plane of motion. He split planes you and goes vertical to slow his forward motion (closure). Once he has his closure and angle off under control, he will roll back into your direction and press the attack again. This is traditional, and therefore predictable, BFM. So you look to where you expect him to be. If you were in a hard left gun jink, then look high and to the right. While this can be done in padlock, it is very disorienting. I recommend that this is best done in external because of the overall scope of the view. If you lose tally in padlock, switch to external to see the bandit.

Tip #7.
Giving the bandit a Head Fake. Sometimes a little trickery is just the thing to bamboozle a bandit. Here’s a defensive ploy that can catch an over eager bandit. Imagine yourself on the defensive. You have a bandit closing in on your six. You want to start a hard turn since the bandit is not yet in gun range, but you do not want to bleed any energy...in fact you want to separate and go on your merry way. So you give him a good head fake...you want him to buy off on it. If he does, you’ll have the time to extend away. Here’s what you do.

Roll into the bandit and show him a lot of planform (that means he is looking at the top of your aircraft). then go full power and start a hard turn into the bandit. Watch him. As he moves away from your six out to about your 5 or 7 o’clock (or more), keep your bank the same but unload to less than one g. You want it to look like you are still in that hard turn. You want the bandit to yo-yo off...when he does, you can extend away.

Tip #8.
The Split S as a defensive maneuver. In the sim world as well as real life, the Split S can be a winner of a defensive maneuver. Here’s why. Most pilots are fairly comfortable in maneuvering nose above the horizon...but when they point the nose down and see a face full of dirt, they tend to have second thoughts. You can take advantage of this. Often, you as the defender may have a better feel for your altitude above the ground as far as a Split S is concerned. You may feel that you can make the turn without going splat. The attacker may not have as good a SA. As you roll over and start your downward pull, a bandit may follow you down...with one big difference...he may pull lead. If he does, he may get a nasty surprise. Just about the time that he is congratulating himself on closing up the distance as he follows you down, he will rapidly become aware that the world is getting very, very full of dirt, very fast. If he is smart, he will abandon all thoughts of chasing you and, instead, go into a full blown dive recovery just to save his miserable skin. He may make it...he may not. In either case, you are most likely long gone. Hey...it ain’t pretty...but it works!!

Figure 25 - Bandit At Your Six - Split S Defense.

Tip #9.
Last Ditch Maneuvers. Sometimes nothing you do works. Sometimes the bandit is the Red Baron and nothing will shake him off your tail. Sometimes you are going to have to throw caution to the winds and bet it all on one last attempt to save your skin. This is known as the Last Ditch Maneuver. Last ditch maneuvers are maneuvering techniques that attempt to force an abrupt role reversal through a severe change in closure and/or angle off. In real life, they typically rely on the extreme negative effect on airspeed that high angle of attack (AOA) maneuvers have. But what works in real life may not work in the sim...and too often this is the case. But, as sim flight models become more like the real world, you may find that you can employ these techniques against your opponent.

Here are two excellent examples...the High g Roll Over The Top, and the High g Roll Underneath. In both examples, the assumption is that the bandit is just about to pull the trigger, and you need to do something miraculous. In this case, miracles can happen!

Both maneuvers are based on you using max aileron and rudder abruptly and simultaneously. They only differ in which way you roll. Let’s set ourselves up in a hard left break. For the roll underneath, we would quickly increase back pressure as we add aileron to continue the roll past the vertical. We coordinate this roll with full left rudder. This is a not a smooth airshow maneuver. Slam the controls into position. You want the stick full aft with full left aileron and full left rudder. The nose is going to whip down and around violently...you will be back to your starting position very quickly. Your objective has been to cause a closure problem that the bandit cannot solve. When you come back to your starting position, neutralize your controls and look for the bandit. Be ready to use your No Tally defense.

For the over the top maneuver, the technique is quite similar. Let’s put ourselves back into our left break. This time, however, we rapidly increase back pressure as we add right aileron and rudder. Again, we does this very aggressively. The result is a nose high roll to the right that basically from the bandit’s perspective appears to stop our forward motion. The drag caused by the AOA of this maneuver is considerable. We are going to come out of this maneuver as a wallowing duck. That’s the bad news. The good news is that the bandit may well be looking at you over his shoulder inasmuch as he has shot past you like a hot knife going through butter. Ta-da!! Now you are the chaser and he is the chasee...what a nice turn of events!! Because of the disorienting nature of this maneuver, I again suggest flying it in external. Use your No Tally defense to look forward and high for the bandit.

What’s the difference between these two maneuvers? Entry energy level. If you are slow, go underneath. Got extra knots to spare? Go over the top.

Closing

This finishes this series of articles. My hope is that you have a better grasp now on how to use the padlock and external views in your offensive and defensive maneuvering. We’ve only scratched the surface here. Many of my suggestions are quite basic and should be seen as general advice only. As your BFM skills improve, you may find that these ideas are too simplistic for your level of game play. All I can say is "Outstanding... You’ve passed the course!!"

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