To add to Lavas suggestion, and taken from 159th Viper in a similar post!
Navigate to your Eagle Dynamics\Ka-50\BlackShark\data\scripts folder and open the options.lua with Notepad++ and find the following entries in red:
["heatBlr"] = 1,
["scenes"] = "high",
["water"] = 1,
["fullScreen"] = true,
["visibRange"] = "High",
["effects"] = 3,
["lights"] = 2,
["haze"] = 0,
["terrPrld"] = "40",
Edit and Save to the following:
["heatBlr"] = 1,
["scenes"] = "high",
["water"] = 0,
["fullScreen"] = true,
["visibRange"] = "High",
["effects"] = 2,
["lights"] = 1,
["haze"] = 0,
["terrPrld"] = "40",
"Note that some of the settings in black are set higher than what i use, i.e, heat blur, visible range"