Hi folks, glad some of you all are enjoying this thread. I have more examples to post but it takes time to get it all together. Here's the next one for folks to chew on!
EXAMPLE 3Here's another example of applying some of these principles in action.
Attached Film:
http://thetongsweb.net/412th/film1_412th+lazer_0001.ahfIn this particular example we'll visit the concept of decision making in a out-numbered, defensive situation. The fight itself evolved from a 1 v 2 to a 2 v many but we'll focus on the initial 1 v 2 situation to illustrate turning principles.
This is also an interesting fight in the sense that there are more enemies than good guys and I'm not above the bogies which means it presents a lot of challenges from an energy management stand point.
FRAME 1In this example I found myself at an energy / altitude disadvantage with two P-38's in my P-51D. The P-38's established in a high six a clock position and started to dive in. As they do so I have a decision to make. Frame 1 depicts how I respond which is to try and turn back into the attacking P-38's.
In the turn back into the P-38's, I'm trying to accomplish two things. First I'm trying to create an geometry problem by increasing the P-38's angle-off-tail (AOT) on my Mustang. Second the increase in AOT can result in a flight path overshoot by the P-38's if they continue to press the attack.
Several key factors play a role in my decision making in this turn back into the P-38's. Assessing the relative energy states I know I'm near or just above corner velocity in my Mustang and that the P-38's are probably even faster than me. Second they are above me which means I can use gravity against them as well (more on this concept later). All this means that my turn radius will be less and turn rate greater than the P-38's allowing me to create more angles than than can gain on me.
In making the turn back into the P-38's, as I see them committed to the diving attack I also make a portion of the turn with my lift vector pointed below the horizon.
As mentioned above in this thread gravity is a factor to consider turns with vertical components. This allows gravity to work with my turn and not against it further increasing my turn performance. Here's another diagram to reinforce the concept:
This images depicts an aircraft making a contant 4-g turn in the vertical. Radial acceleration represents the acceleration due to lift while normal acceleration is the total acceleration experienced by the aircraft including gravitational acceleration. Essentially normal acceleration is the absolute acceleration experienced by the aircraft while radial acceleration is what we read on the accelerometer (g-load meter) in the plane.
Notice that at the bottom of the "loop" that gravity works directly opposite that of lift. This results in an absolute acceleration of 3 g's instead of 4. The net result is that the turn radius is increased and turn rate decreased. This is gravity working against a turn. At the top of the loop the effect is exactly opposite. Notice that the absolute normal acceleration is 5 g's instead of 4. This is because gravity is working in the same direction as lift and the net effect is reduced turn radius and increased turn rate.
Okay let's see what happens next.
Frame 2In Frame 2 one P-38 presses the attack while the other holds high. As can be seen the turn back into the P-38's and the increased AOT causes the attacking P-38 to overshoot. This is another decision point. What should I do in the Mustang? Should I keep turning to my left? Should I straighten out? Should I turn back into the P-38?
Two factors are key in my decision making:
A)I haven't blown a bunch of energy in my turn and am still near corner velocity. Things that helped this - It was made with a slight climb to trade some speed for altitude before going oblique nose low and reefing it in. Also I have WEP on to counter the energy-bleed in a max performance turn.
B)The P-38 has a bunch of smash (374 mph) and well above my corner velocity but also now moving into a lag pursuit position on my P-51.
So it appears I'm at my max turning potential while the P-38 will turn worse. However the P-38 is now moving into lag pursuit which means that if I continue my turn in the direction I have been he can use a lag pursuit curve to negate any angles I can generate more than the P-38 and get into a advantageous position.
When these factors in mind I thus make a nose-to-nose turn back into the P-38 which is depicted in Frame 3.
Frame 3The P-38 continues to press the attack in a nose-to-nose direction and is able to get a brief snapshot which I risk. Note that my reversal back into the P-38 is again with lift vector pointed below the horizon to get a gravity assist in the turn. Since I'm near corner and the P-38 is faster than me I know that overall I can create angles without having to blow a lot of energy in the nose-to-nose. This is important because I know that I have to bank up as much maneuvering potential because having the P-38's wingman just on top as well as having plenty of other bad guys close by.
The nose-to-nose forces another decision point. The P-38 and I cross paths. Which way do I turn now?
Frame 4Frame 4 shows the choice I make. This time instead of making a nose-to-nose back into the P-38, I stay in the right hand turn which means I'm now in a nose-to-tail turn instead. Key factors in making this decision:
A) I've created enough angles between the first P-38 and am picking up some energy in the process. Because of the high threat environment I'm now trying to get him to expend energy while I gain it to give me options. The nose-to-tail turn increases my separation and also causes the first P-38 to have to go through a lot more angles to get pointed at me. I'm hoping that he does that to start changing the energy margin. As can be seen that's starting to happen with me now at 335 mph and him 288 mph.
B) 2ndly all the while I've kept an eye on his buddy and am trying to increase AOT for the 2nd P-38 that is now pressing his attack on me too.
Frame 5In Frame 5 the first P-38 is essentially no longer a factor thanks to the nose-to-tail turn, however the 2nd P-38 is diving in now for the attack. Which way should I turn now?
I respond to the 2nd P-38 by turning back into him in the pure vertical. Key in my thinking is exploiting gravity so that I'm using it for me while simultaneously using it against him.
Remember that in the vertical if your lift vector is oriented below the horizon then your turn performance increases while having your lift vector oriented above the horizon decreases your turn performance. In a pure vertical turn / loop, the bottom half of the loop between the points where an aircraft's lift vector is 90 degrees to the horizon and the aircraft going straight down or straight up, gravity is working against you.
Frame 6 depicts what happens next.
Frame 6Upon the merge with the 2nd P-38 I continue the direction of my turn creating a nose-to-tail turn with the 2nd P-38. I'm doing this again to gain separation and energy from the 2nd P-38 as well as actually setting up a merge with the 1st P-38 trying to get back into the game.
With the 1st P-38 I point my nose at him and merge as close to head-to-head I dare possible without getting hit from a face shot demonstrating the principle of trying to counter any vertical separation room that he has to use to create a lead turn into me.
The fight eventually leads to me and Lazer conducting a fighting egress against the bad guys bagging some kills in the process. In the direction of turns made it possible for me to take away the initial energy and angles advantages the P-38's had eventually allow the fight to be dictated on the good guys' terms
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Tango, XO
412th FS Braunco Mustangs