An Introduction to Simulation BFM Part One

by Andy Bush

The following articles were written several years ago in support of a web site devoted to Janes ATF, and later, Fighters Anthology (FA). Much of the material is of a general nature and may be applicable to all sims. Newcomers to air combat simulation may find this material helpful in understanding some of the terminology of air combat.

For those of you interested in the technique of learning and flying BFM while using the player-to-target external view can find some tips here. The FA sim has several features that make it a good choice for practicing BFM with the external view. In particular, you may find the explanations of how to fly a variety of specific maneuvers to be helpful.

There are no illustrations to these articles, however, many of the techniques are covered in the “It’s All A Matter Of Perspective” series of articles.


BFM – An Introduction

Is this flight sim stuff a good thing or what? Well, that’s what I think, at least. And the more I have thought about it, the more I wanted to bring some things up for discussion. So, here we go…..what I’m going to do is to throw some ideas and observations out for you all to chew on, and, then, maybe you’ll get back to me with your thoughts on the subject…as a result, we’ll both end up a bunch smarter.

Number One Question: What are we trying to do here? There used to be a cigarette commercial in years past that asked the question “Do you want good flavor or good taste?” Well, that sorta sums up the big question in my mind regarding flight sims…do you want arcade fun or real world realism? The answer is most likely…both!! Some want plain old shoot ’em up flying, and others want the complexity of planning and executing a multi-plane attack on poor old Saddam. OK, we can have our cake and eat it too. Today’s sims allow a wide spectrum of user activity, and no one should poop in the mess kit of one side or the other. There’s plenty of fun to be had by all!!

For me, the action is in one versus one aerial combat…you know, the TOPGUN rat-a-tat-tat “I gunned you before you gunned me” kinda stuff. And the reason is real simple…it’s just more fun than the law allows. I wish all of you folks could experience the thrill of an air combat training mission…to say that it is an exhilarating experience is not doing it justice! Win or lose, it’s a supercharged, heart thumping, palm sweating, breath taking event that will forever more alter your view of the world around you. After everything is said and done, you will know that you are well and truly alive and that you have seen and felt things which mere mortals never will.

Having said that, I want to put in a pitch for good old BFM. That’s Basic Fighter Maneuvers that I’m talking about. Forget about AMRAAM face shots for a moment…let’s look at how the military starts their pilots out. F16 students, once qualified in basic transition, formation, and instrument skills, go straight into air-to-air training. You might think that strange…why not start off in air-to-ground…that’s gotta be easier and less complicated…why not leave the three-dimensional air-to-air stuff until the end, you might say. The answer is simple. It’s a matter of staying alive. Screw up a BFM maneuver, and you get to try it again. Most BFM training flights are flown in the medium altitude region…10,000′ to 20,000 ‘ above ground…big margins for error.

Air-to-ground…now that’s a whole different ball game. Mother Earth is very unforgiving…start your pull out too low and you’ve just become the lead off item in Channel Three’s six o’clock news report, and the news ain’t good.!! The military treats air-to-ground maneuvers as BFM flown against a fixed objective with a very hard “floor” located right at target altitude. So, BFM is learned at a safe altitude and in an air-to-air context to start with…then training moves into the real serious stuff, ie pointing your warm body at the ground. No matter, we’re still talking BFM.

So, you ask, what is this BFM stuff? What is it all about? Real simple…here’s the answer. It’s about controlling your position and energy state relative to the bandit. It’s about controlling fuselage alignment and closure. It’s about keeping him in front and you behind. It’s about winning or losing!! BFM is the heart and soul of fighter aviation. No matter what your mission objective is, you must be able to put you and your jet into a specific part of the sky at a specific time. Be in position and don’t be late…or early for that matter!!

Want to know more about this? That takes me back to my original point. Tell me what you think…or throw some questions my way. I’m game…how about you? Follow-on discussions will relate real world BFM to the limitations and restrictions of the view of BFM provided by the computer monitor.

BFM Lesson 1- What Are Your Objectives?

With all the super work that Greg has done in providing us all with a wide selection of aircraft to fly, there naturally have followed a number of questions regarding how a particular aircraft should be flown against specific opponents. I’d like to take a moment to talk about that.

My experience with flight sims, the flight sim media, and the folks that fly them has left me with one singular insight…simmers who want to maximize their enjoyment of their flight sim are hungry for any and all info on what “it’s really like.” While I think such enthusiasm is outstanding, I think a little reality check is necessary.

First and foremost, a flight sim is only going to “fly” in the manner that it was programmed. If it wasn’t modelled correctly, then the sim aircraft cannot be compared to the real thing…and with that in consideration, it then follows that prescribing real world tactics for that aircraft may well be wasted effort. Fortunately for us all, Greg continues to go to any length to make his lib aircraft fly as realistically as possible. But neither Greg nor anyone else can provide other intangibles such as actual G loads, 360 degree vision, and a intuitive sense of “the big picture” which are such a major part of actual BFM. These are limitations which the flight sim environment has tremendous difficulties in replicating. Once we recognize this, then we can go about the business of making what we have work as well as possible. Having said that, let’s move on to some specific suggestions.

I’ll start off by raising the question of what you want to get out of the sim…do you want a missile “kill” at BVR ranges, or do you want to get in and mix it up? The answer to this question leads directly to how you expect to fly your jet…a “face shot” at 15 miles doesn’t require a lot of BFM on anyone’s part. On the other hand, a guns only environment almost always will. For the purpose of this discussion, I’ll limit myself to a guns only situation, and then discuss aircraft performance with that in mind.

When we talk about relative performance these days, it’s common to hear the terms “angles fighter” and “energy fighter.” In years past, this was expressed as “turns better / accelerates worse” and “accelerates better / turns worse.” Please understand that this is all relative. A MiG-17 was an “angles fighter” when opposing an F-4, but against a P-51, the MiG is in the other category. So when you choose a jet to fly, you have to take your opponent in mind. You certainly want to play to your aircraft’s strong points while minimizing your opponent’s advantages. Taking a heavy F-16 into a knife fight with a MiG-29 may not be the thing to do.

So what’s the answer? I suggest less interest in how a specific aircraft matches up against another…instead let’s take note of those performance advantages of our jet…good acceleration, let’s say…and then plan our moves accordingly. Perhaps an example is in order…I’ll choose the F-104, a long time favorite of mine. I’ll make the assumption that the sim aircraft is modeled fairly accurately. I’m then going to play to my strong points…better than average acceleration, high top end speed, and a decent but not spectacular turn ability at corner velocity. Remember, we’re talking gun only here. My objective will be to take away my opponent’s turning room…I don’t want him to lead turn me. I’ll keep my speed up…over 500KIAS…to retain as much energy as possible to be able to extend out of gun range as conditions require. I’ll expect most of my attacks to be slashing, high angle gun passes…probably not a good idea to try and slow down to attempt a more conventional low angle tracking shot. Vertical extensions…trading airspeed for turning room in the vertical…will be a major item in my bag of tricks. Lastly, I’ll think of my maneuvers as extensions and hooks…meaning straight line acceleration to gain separation and then a rapid deceleration to corner for any required turns.

But what if you prefer an angles fighter? Well, I just so happen to have some experience in that too. Flying the A-10 was total fun, but no one ever accused it of being an air-to-air machine!! But it could hold its own in a fight when flown to take maximum advantage of its strong points. These were an amazing turn rate and radius and a real big gun that shot a whole bunch further than anyone else could. My tactics in the Hog were to lead turn my opponent to keep forcing him out in front. I took the fight down low to deny him turning room below me. I only went into the vertical to take a shot. I kept my smash up as much as possible to minimize his ability to extend away easily. And I waited for him to screw up. Most gun engagements are not won…they are lost. There are F-15 and F-16 drivers out there who have found themselves looking at the wrong end of a Hog and were left wondering how in the world such a thing could have happened.

OK, let’s wrap this up. I’ve tried to make several points:

1. Know what you are flying. It will only fly as well as it has been modeled. Fly it according to how it is modeled, not how the real aircraft flies.

2. Know what your goal is…a quick kill or a knife fight.

3. Know how your opponent stacks up against your jet. Are you going to be an angles or an energy type of jet versus your opponent?

4. Fly to your strengths and take advantage of his weaknesses.

BFM Lesson 2 – The Basics

Let’s talk a bit more about BFM, but first how about a little book learning’ on terminology<g>.

BFM, Basic Fighter Maneuvers, is just that…basic offensive and defensive maneuvers flown by one aircraft against a single opponent. BFM is intended to teach the basics of 3D maneuvering with emphasis on spatial relationships and control of airspeed…which is a fancy way of saying that the maneuvers are intended to keep your opponent out in front of you or, if he is behind you, the maneuvers are meant to deny him a firing opportunity, or even better, make him overshoot and become defensive. BFM is 1v1 set piece maneuvering to a desired end result.

ACM, Air Combat Maneuvers, is the next step in the building block concept of air-to-air training. ACM involves a pair of fighters solving a defensive or offensive problem being presented by a single opponent. ACM is 2v1 and involves the practice of initial defensive or offensive moves. As in BFM, the maneuvers are set piece, are begun from a visual set up, and are flown to a pre-briefed conclusion. ACM is not free play…the fighters follow a script to a desired learning objective using BFM maneuvers to defeat the single opponent.

ACT, Air Combat Tactics, is what most folks think of as dogfighting. The numbers of participants is not limited…everything from 1v1 to many v many. There is no script in that no specific objective is mandated. ACT involves the blending of BFM and ACM techniques into free play. DACT is Dissimilar ACT, meaning the opponents fly different types of aircraft. ACT can be flown from a visual set up or BVR. ACT is the final building block in air-to-air training.

Now, this doesn’t have much to do with flight sims other than to make clear that terminology in the air-to-air business is very important. If you wanna do the walk, ya gotta know the talk<vbg>. In the real world, all of this is written down in a document called “The Engaged Fighter / Supporting Fighter Contract,” which lays out in very specific language who does what to whom and who is responsible for what in an engagement. Guys have died not following these rules. You may not need this level of learning to enjoy your flight sim, but if you are going to use air-to-air terminology, I’m sure you would want to do it right.

Whew!! Enough of the classroom stuff, let’s have some fun!! For starters, let me remind everyone that these discussions assume the sim aircraft fly according to sim flight characteristics (not real life) and are based on a gun only environment.

We’ll concentrate on BFM maneuvers and try to describe them as you would see them on your monitor. First, let’s recognize up front thelimitations of the monitor. As we all know so well, visibility is restricted, particularly in the 12 o’clock high area. This is a critical shortcoming in that the 12 o’clock high area is where your lift vector is, and your lift vector is what determines your aircraft’s future flight path. If you can’t see where you are going when you are pulling on the pole, then you are in deep doodoo <g>. In most current sims, the hat switch on your flight stick can slew your view up and give you that high 12 o’clock view, but you must be very careful with your aileron input if you try this. Any roll input while you are using the hat switch to look to high 12 will most likely be very disorienting. The same is true of any slewed view using the hat switch…use the hat switch as an aid to finding the bandit, but do not try to maneuver using it…switch back to your forward view and then make your flight path change. Continue to use the hat switch to monitor your progress.

Another restriction to visibility is the cockpit frame / HUD depictions. I strongly suggest you choose a forward view that does not include the HUD frame if your sim choices permit. The sim’s portrayal of the cockpit frame / HUD may be fairly realistic from a technical point of view, but ends up being a restriction to forward visibility that far exceeds the extent to which your vision is restricted in real life.

Along this same line of thought, if flying ATF/ FA, try to put any windows that you use at the bottom of your screen…this frees up the top of the monitor for maneuvering use as you roll your a/ c to position the lift vector.

Probably the most popular view for following a maneuvering target is the padlock view. Many competition ladders require this view. The main problem in using a padlock view is keeping oriented to where your nose is. For this purpose, most padlock views contain cues that allow you to “see” your nose position. These cues include canopy markers (as in EF2000 and F22 ADF) and mini-windows (as in Falcon3) and are intended to show the location of the lift vector. These cues allow you to point your lift vector relative to the target’s position in the padlock screen. This technique takes a great amount of practice to become proficient with, particularly if the pilot is using the cues to maneuver out of the plane of motion of the target. The padlock user should avoid using the lift vector to aim right at the target…this is known as “lift vectoring“…doing this results in a “g for brains” pure pursuit chase of the target and is not good BFM. In fact, it will only work if you have a turn advantage over the target.

The external views can be used to help you visualize a BFM maneuver. The main problem with using external views are remembering which way is left and right as you view your aircraft! As with the padlock technique, these views require practice to become proficient in, but they are the best viewing choice to learn the three dimensional BFM maneuvering environment, i.e. seeing the “big 3D picture”.

Lastly, let me put in a pitch for peripheral hardware. Both Thrustmaster, CH Products, and Saitek make excellent flight sticks, throttles, and rudder controls. The advantage of a programmed flight stick and throttle cannot be overstated. The less you have to go to the keyboard, the better. Weapons selection, view control, speed brake, chaff / flare / ECM, and radar operation need to be at your finger tips. You can leave the gear and flaps on the keyboard, but try to program your controls so that you can fly “heads up” as much as possible. Looking down to the keyboard should be minimized to reduce the possibility of losing sight of the bandit.

Now we are ready to do some flying! Part 3 will begin a discussion of actual BFM maneuvers.

BFM Lesson 3 – Configuring The Sim

Well, it’s time to strap on the jets and do some flying, but first, we need to brief the mission. Let’s talk a bit about how we want to configure the sim to maximize our training. Today’s mission will be a basic one v one set up with you on the offense. Here’s some suggestions that work well for me. I’ll use ATF/ FA as a frame of reference…the ideas translate easily to other sims.

1. Preferences. Selection of aircraft. Using the Quick Mission Creator screen, pick a maneuverable jet…and select a less maneuverable for your opponent…for example, you might choose to fly the Super A-4 against the A-7. The idea here is to give you the advantage while you are learning the basics.

2. For your mission parameters, select Situation=Advantage, Separation=1 nm, Standard Weapons load, Altitude=5000 ft, Weather=Clear, and Guns Only. This puts you behind your opponent in a good position to begin maneuvering.

3. Level of Difficulty. On the Enemy Situation screen, select only one opponent. Initially choose Novice as his experience level…as your ability improves, you can up the ante.

4. Basic Screen Set Up. We are going to practice basic BFM maneuvers against a maneuvering target. The major problem with BFM and flight sims is that the very nature of BFM…maneuvering relative to our opponent while our aircraft is not pointing at him… results in losing sight of his aircraft. So now we have two problems to fix…flying the BFM maneuver properly, and keeping a tally ho on the other guy. Fortunately, ATF allows us to do this by changing our selection of views. This is how I configure my screen:

a. Frame Rate. Reduce graphics level to minimum ground detail to improve frame rate. I keep aircraft detail on high because I like looking at pretty airplanes<g>.

b. Turn Transitions off to speed up changing from one view to another.

c. Make an Other View window that shows your forward view. Do this by selecting F1 to put you in the forward view. You want to have the Other View window at the bottom of your screen…do this by selecting other windows first…do this until you have these at the top of your screen. Then select V. This should put the forward view window at the bottom of your screen. Then turn off the other windows by mouse clicking on their number located in the upper left corner of their window. You want the top of your screen empty because that is where the majority of the action is going to take place, and we don’t want it cluttered up.

d. When you initiate play, select Slow Motion by pressing Shift + C. This will slow down both your aircraft’s maneuverability and your opponent’s by 50%. Doing this at first will give you the time to recognize the need for a given BFM response and will allow you to fly that response slowly so that you will see the effect of the maneuver. Regular roll rates and opponent AI response is too aggressive for beginners.

e. Finally, plan on using the F7 external view anytime your nose is off your opponent to the extent that you no longer see him. Use the + and – keys to zoom the F7 view in or out to provide the clearest picture of the action. When in the F7 external view, use the F1 window to keep track of where your nose is relative to the horizon…in real life, a pilot’s peripheral vision “sees” the horizon and constantly updates him on his attitude relative to the horizon. The significance of this will be explained later when we talk about energy and “God’s G”.

5. OK!! Let’s summarize our game play configuration. We’re going to fly in F1 until the bandit flies out of view…then we switch to F7 and continue to maneuver relative to the bandit. We use the F1 window to keep track of the horizon…and when we have successfully maneuvered back behind the bandit, we can switch back to F1. We fly in slow motion to begin with so we can see the maneuvers more easily. Improve your frame rate by keeping your graphics demands low and turn Transitions off to speed up view selection. Start from a 6 o’clock and one mile back position from your opponent…guns only.

6. So if there aren’t any questions, let’s mount up and get to work. Follow-on discussions will address basic offensive BFM maneuvers. See you then.

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