[socorrista22198]

Yes you can replace the original airshow trails for 3d smoke. Open with notepad \IL-2 Sturmovik 1946\Files\3do\Effects\Aircraft\AirShowGreenTSPD.eff and AirShowRedTSPD.eff and replace all by this (if you don´t have this files create them):

[ClassInfo]
ClassName TParticlesSystemParams
[General]
MatName ../TEXTURES/Smoke.mat
Color0 0.9 0.9 0.9 0.2
Color1 0.804 0.816 0.912 0.0001
nParticles 4096
FinishTime -1
MaxR 20
PhiN 2
PsiN 1
LiveTime 10
EmitFrq 50
EmitVelocity 10 15
EmitTheta 0.2 10
GasResist 0.05
VertAccel -0.1
Wind 2
Size 0.7 50
Rnd 0.8

(it´s the ultrapack settings)

The Color0 and 1 section is where you can play with color: red green blue opacity (values 0 - 1, 0=black and 1=white)