In the P-38, if you are somewhere between 115mph and 100mph IAS with 3/4 flaps deployed, you can pull into a loop and as your plane starts to stall as it begins the top part of the loop, deploy the last notch of flaps and this will cause the nose to swing down, bringing you over the top of the loop.
If you deploy the last notch of flaps at the correct time, your plane will do more of a flip with the nose pointing straight down instead of a loop. If you do it early or too late, you run the risk of wallowing on your back as long as it takes you to kick the rudders to swing that nose down. So doing it early or late will most likely result in your death.
When my nose is pointing down again, I'll raise one notch of flaps back to 3/4 deployed. If the maneuver is done correctly and time right, it can lead to a very nice shot opportunity on the other plane as they try to maneuver to match you. If at this time I have a shot, I'll take it. If I don't have a shot and the other plane continues to turn, I usually do another stall loop or sometimes I'll go into a High Yo-Yo and as I near the top of the Yo-Yo, stall my plane out and roll it over, again deploying my last notch of flaps as I near the top and start the beginning of the Yo-Yo and raising it immediately after my nose swings downwards again.
Throttle control is also important as when you go into the stall loops, I have the throttle at 100% with WEP on and then as I start the loop, I chop throttle and deploy the last notch of flaps to full. When the nose swings down, I slam the throttles to full, hit WEP and raise flaps to 3/4. This allows me to recover with minimul loss of altitude and recover enough energy that I can perform another stall loop if necessary.
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