P-3C Orion FSX is required in order to use this model.
Download is unnecessary when you already have this model. There is no change at all with it.
FSX_Fire_Retardant_Effect is in SOH.
If it enters appropriately to [LIGHTS] in aircraft.cfg, an effect will appear by operating the Fire Retardant Spraying switch in VC.
(Refer to the New assign.jpg.)