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Introduction to Energy in Air Combat

From Fletchman: Good evening, I'm Fletchman, your host this evening. Tonight's topic is "Introduction to Energy in Air Combat".:

From Fletchman: This is one of our continuing series of lectures by the Warbirds Training Staff:

From Fletchman: Any preliminary questions?

From Lephturn: How do I conserve E in an FW :):

From Fletchman: Don't turn too much. It bleeds E fast for an E-fighter.

The influence of Energy on air combat is so profound that I don't think that I can cover all the material in one lecture. Tonight I am going to concentrate on defining basic energy concepts and how they affect air combat, and some Question and Answer Sessions thrown in. If all goes well, I will cover some more material in future more advanced lectures. I plan to define and cover material on " Boom & Zoom -The Classic Energy Fighter" and if there is demand for the topic. "Energy Concepts for Duels, & Furballs". That is Energy tactics for other than the strict B&Z flyer.

I might want to make a comment up front. While many folks equate E-fighting to the classic "Boom And Zoom" dive-shoot-climb tactics, there is much more than simple B&Z involved in understanding Energy. In fact when you fully understand that concept you will be along way to understanding what energy is really all about.

From Fletchman: We need to consider Energy in Air Combat for a number of reasons..

One - Gravity! It works. Two - the less than infinite thrust-to-weight ratio we suffer with in WW II combat Aircraft, and drag. Thirdly, the Weapons we employ have a limited range and arc of fire. Sadly, they mostly fire forward and from a fixed mount to boot. And finally - we live in 3 dimensional space.

So what does this have to do with Energy? Well the fact is that we fly planes with rather limited capabilities makes energy a vital part of air combat. If we had planes with unlimited climb, acceleration, and "wish 'em dead" guns that fired at all angles, Energy would be a mere speck on the horizon. But sadly we need Energy to win in Air Combat!

As the Outlaw Josey Wales said "We need and Edge!". Energy is a tool used to help us engage the enemy on favorable terms. Because the target plane has the same weaknesses ours does.. I suppose you all might be wondering where all this is leading, I still haven't really defined what energy is. I suppose I should start a lecture on Energy, by making some attempt to define it! Well if it was easy, there would be no need for this lecture! From Fletchman: any questions?? From Pete: Could you use the F4u in your examples and will you be quoting from Dirty Harry movies too?.

(Note: At this point Fletchman is was Disconnected from the BBS Forum)

Fletchman just switched to this channel!

Welcome back.

From Fletchman: Back! sorry about that! Good time to get dumped. Ok, well after that short break shall I start again? Ok I think I was about to work on a definition of Energy when I was rudely interrupted by the Net Gods... really. I think I missed a question just as I got dumped that didn't get answered!:

From Lephturn: Somebody wanted you to use the f4u for examples.:

From Fletchman: Ok, going to work on a basic definition and I'll try to work on that after we get some more groundwork done. A simple definition of Energy is simply a sum of altitude and speed. And speed defines initiative in engagements in the rawest sense. A fast fighter can close with a slow fighter and attempt a gun pass with that short range limited arc set of weapons I just mentioned a bit ago before I got dumped! Energy is a bit more complex than that of course.

A fighter at 500mph who is 3000 feet below a fighter at 100mph should have an advantage in Energy. Let me use an analogy to explain this a bit. Altitude is like a bank you deposit "energy bucks" in. When you Zoom Climb for instance you are trading speed for altitude, but your Energy is probably staying fairly constant. You are depositing energy for a rainy day. Speed up in a dive and your energy level will degrade slowly if you level out. Unlike altitude - raw speed falls to Max level speed in due time, thus losing energy.

The energy inherent in altitude remains relatively constant. When you convert altitude to speed in a dive you are writing a check as it were on the "Energy Bank" of altitude. Once you write the check you may not get the energy back unless you make some more deposits in the "Energy Bank" fairly soon! The fighters engine provides a constant "income" of energy. But in WW II planes the income level is pretty miserly. (Remember that abysmally low thrust-to-weight ratio?) That's why to build up a significant energy level you often have to "bank" it by with a climb of some sort. That's why Energy Fighters tend to obsess about altitude because altitude represents a firm basis for energy while simple speed is temporary. From Fletchman: Any questions?

From Lephturn: Given equal e, better to be low and fast though?:

From Fletchman: Not necessarily - equal E implies a comparatively equal freedom of maneuver regardless of altitude, but speed implies ability to maneuver, which may give that fighter the advantage.

From Lephturn: But the fast guy can attack or bug, but the high guy must convert first?:

From Fletchman: Depending on the tactical position and the current disposition of the aircraft involved. In other words, who might have the angle advantage etc. Glad that you asked that because it leads in nicely to the next subject.

From Aadrian: When you climb for E should one keep his speed up, or climb fast?

From Fletchman: Well, as a general rule its a good idea to maintain a bit of airspeed under all conditions in case you get surprised which can always happen. If you get caught slow in a climb it will take time to gain speed for a maneuver. You are probably a sitting duck for a surprise attack.

From Lephturn: But too much speed would bleed e, so happy medium?

From Fletchman: Generally 150 + is OK. Climbing at stall speed leaves you a dead-duck. As you said, develop a happy medium. Most fighters have a best sustained climb speed which is usually in the 150-170 range so that's a good speed to go for. If you happen to be the scholarly type, you could research the best sustained climb of the fighter you fly the most and use that speed.

From Fats: Pyro has been so kind and made climb graphs available for us... I believe they might be available in this BBS.

From Fletchman: Yes, the performance graphs are enlightening reading. Its always wise to know the comparative strengths of your aircraft - especially in relation to other aircraft.

From Sniper: Have charts been made available for all the other plane types not just Kiel planes?

From Fletchman: Not sure Sniper... good point. If I remember, all planes were listed on the ones I have. It even had the spit 5.

From Fats: P-38J, P-51D, FW 190A-4, Spitfire IX and V, Zeke, P-39D

From Fletchman: Anyway, lets get back to the subject at hand. Let me get into the relationship between energy and tactics. Let me talk about Energy by covering a bit of basic tactics.

Fighters are offensive weapons, and offensive weapons work best when they fight from positions where they, not the enemy have the initiative. The pilot, to be successful, needs to maneuver throughout the fight to assure that he and not his opponent dictates the pace of combat, starts with the initiative, and keeps it throughout the fight.:

Initiative is a bit hard to define in itself but we can say its freedom of movement and or some kind of tangible advantage that could be used to turn the fight in your favor. There are two forms of initiative in Air Combat. Angle and Energy. Both concern themselves with gaining firing position within acceptable gun range and dispatching the opposition. The angle fighter concerns himself with gaining a firing position by the most obvious means in what most flyers would term the classic dogfight; that is a maneuvering combat at or near stall speed where one fighter attempts to gain firing position on the target by means of often sharp and violent high-G maneuver. This is a rather simplified definition of course but serves the purpose for now. However the wise pilot considers energy in the equation as well.

Its a base fact that slow planes can't maneuver well, especially near stall speed and certainly can't catch another plane. The Energy conscious pilot uses Energy, and the freedom of maneuver and initiative implied therein to favorably reconvert energy to angle at the appropriate moment. The magic of how to go about doing that will be the subject of my follow on lectures!! (:

To really understand Energy one must also understand how it relates to Angle in deciding the fate of air combat. Energy and Angle can be seen as a sort of a sliding scale in a fight. Both are needed to win most air combat fights. But if you gain one you may be giving up the other! A tough decision! They have to work together, and the misuse of either can lead to defeat.

A simple example is: If you pull hard on the stick you might gain angle, but you are sacrificing energy by pulling a high G-load. Hi-G maneuvers it should be noted drain off energy at a tremendous rate. The reasons for this are technical in the extreme and longwinded. The fairly simple explanation is that as your G load goes up numerically, one component of drag (that nasty thing that slows down your plane) goes up exponentially. The Super Simple version: a Hi-G turn acts as an Air Anchor.

This is a fact that most beginner pilots often fail to appreciate to their everlasting regret, after they are shot down time and time again. If you do a lazy low-G turn or just fly straight you will mostly likely lose angle, but gain comparative in energy state as your opponent bleeds off Energy in a high G-turn. If your opponent doesn't get an immediate gun solution you have may have gained the initiative. However you must later have sufficient energy to reconvert it back to angle (which you have lost) and then get into a firing position! That is the dilemma of using Energy in a nutshell.

From Fletchman: Any questions?

From Flanker: Losing energy in a high-G turn is the same thing as "bleeding" energy, right?

From Fletchman: Yes Flanker because of the very high drag induced in a high G turn, total energy loss (bleed) is substantial. One reason most "E-fighters" avoid Hi-G maneuvers.

From Flanker: So the advantage to an "anchor" high-G turn would be to still have a good angle while gaining energy back?

From Fletchman: Well if you have substantial E advantage you can often reconvert it to angle by using a hi-G turn. If that results in a good gun position and a kill you have ccomplished what you intended. Energy is just a means to end -shooting down those bad guys!:

From Gunsnake: Is there an energy efficient reversal maneuver?

From Fletchman: Yes, a low G Immelman, or Chandelle climb are both good for E retaining reversal.

From Oldsetter: How do accomplish a low G Immelman?

From Fletchman: It's an Immelman with minimal G load; that is, a half loop followed by a half roll. Chandelles basically are a climbing turn to either side. Chandelles are related to lag pursuit tactics, an important part of E-fighting tactics which I will get to in the more advanced lectures in the future.

From Nerf: Why Chandelle instead of Immelman when the former is more E-expensive? Is it?

From Fletchman: Both are efficient. From a technical standpoint I couldn't say which is scientifically the most efficient, probably the Immelman. Since the Immelman does not expend energy laterally. The maneuver depends on the tactical position Nerf.

From Nerf: cc is "Chandelles" just a pretty name for a spiral climb?

From Fletchman: Yes Nerf, more or less.

From Nerf: What tactical position warrants it?

From Fletchman: Well that's an ACM question Nerf, that is a bit more advanced than I want to go into detail about here tonight.

From Fats: ICI has a good page explaining the "Chandelle".

From Hardcase: Chandelle is at your leisure... immediate.

From Fletchman: You could choose one over the other depending on how much separation is appropriate. The mmelman can be used more easily to instantly reconvert energy to angle, while the Chandelle, as I said, is useful in a lag pursuit type maneuver, i.e. maintaining energy advantage without going for the immediate payoff of a gun shot.

From Oldsetter: Just seems like Immelman in a combat situation would be hard to do as low G.

From Fletchman: No... A low G loop is often a killing move, essentially a very high Immelman. Well let me clarify that... The very high move can lead to a loop over to a gun shot or the technical Immelman used to maintain a position above the enemy!

From Gunsnake: This could touch on a few areas not being discussed now . These maneuvers your describing seem to be okay... when the other poor bastage :) is flyin' straight and level....what about when he ain't?

From Fletchman: Well, the moves apply to most situations. Exactly how to react to specific defensive moves is something I will cover in next lecture (I hope)

From Gunsnake: Sorry, just figured it out... The idea behind these man's are to gain an ADVANTAGE

From Fletchman: Right...let me move on then. Let me provide a bit of warning or practical advise for the new flyers. The biggest mistake most new flyers make is that they think only of angle. That is they yank on the stick constantly in an engagement attempting to gain angle by the simplest means. However they may find themselves gaining angle only to see it lost when they are suddenly at stall speed, while the target they were "yanking and banking" after suddenly converts his energy advantage by climbing over their head (a move they cant match) and dropping on their wallowing planes six for an easy kill.

Position is only useful if you can use it to get a gun shot, either a snapshot or a "saddle up" position..Position is meaningless against a plane much faster that you have no shot at. That is to say, Position is transitory for the Energy Fighter, in fact the E Fighter often surrenders angle (position) to enhance his comparative energy state. The Energy Fighter can later use that energy to perform an angle gaining maneuver that the slow fighter cannot match and regain position.

While the stall fighter lives to obtain position, the E fighter with its slower turn rate and (it is too he hoped) higher speed cannot hope to turn with its target on a majority of occasions. But it doesn't have to! By using energy wisely, the E Fighter can almost always regain position for that "moment of truth" shot. The high yo-yo is a classic example of this. The Energy fighter can perform an out-of-plane vertical maneuver the slower plane cannot match, and is able to convert his Energy to angle (for a shot) by the astute use of the 3rd dimension. Energy and angle often have a rather symbiotic relationship in air combat, hopefully I will explain that more fully in the follow-up lectures. Ok, I would like to throw it open for general questions now. Anyone have comments or questions at this point?

From Aadrian: Still trying to figure out how to convert E to position.

From Fletchman: Well, say a Low-E plane is in pursuit, but out of gun range. You pull back gently on the stick to begin a loop, the Low E- plane attempts to match the move but cannot. As he stalls out in the climb you loop over, and then drop on him from above and put the hurt on him.

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