FX definitions in CFG files with multi-mode parts

[Mrwood]

I am attempting my first mod and I've been able to modify a jet engine B-9's F-119 to include a non-afterburning and an afterburning mode in terms of performance. I'd like to add specific FX definitions only when the afterburner is engaged, and then be removed when the engine is switched into non-afterburning again. Can anyone tell me how to make FX effects phase in and out? Thanks in advance, CFG file extracts below:

...

// --- FX definitions ---

fx_exhaustLight_yellow = 0.0, 0.0, 0.0, 0.0, 0.0, 1.0, power

fx_smokeTrail_light = 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, power

// I want this to only engage on AB mode

// fx_exhaustFlame_blue = 0.0, 1.0, 0.0, 0.0, 1.0, 0.0, power

fx_exhaustSparks_flameout = 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, flameout

...

MODULE

{

name = HydraEngineController

primaryModeName = Mil-power

secondaryModeName = Afterburn

// Mil-power Mode

primaryEngine

{

...

// Afterburn Mode

secondaryEngine

{

...

MODULE

{

name = ModuleAnimateHeat

ThermalAnim = jet_engine_f119_heat

}

I'm not certain but I think this controls the nozzle flaps in conjunction with the control surfaces.

MODULE

{

name = FXModuleConstrainPosition

matchRotation = true

matchPosition = false

CONSTRAINFX

{

targetName = lookatfx_target1

moversName = plate1_holder

}

}