Rationale : Heavy Fighters have a 30 degree turn rate, rather than 45.
This means that a 3-card Immelman just doesn't reflect their limited ability here.
Optional Rule:
Heavy Fighters Immelman - Fast Straight, Climb, Reversal, Climb, Slow
Heavy Fighters Split-S - Stall, Dive, Reversal, Dive, Fast straight.
Basically insert a climb or dive before and after the reversal.
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