Never: Disables the ability for AI to use their ECM.
Use if Lock By Radar: If the AI is actively being locked by an enemy radar they will enable their ECM jammer.
Use if Detected by radar : If the AI is being detected by a radar they will enable their ECM.
Always Use: AI will leave their ECM on all the time.
NEVER_USE = 0
USE_IF_ONLY_LOCK_BY_RADAR = 1
USE_IF_DETECTED_LOCK_BY_RADAR = 2
ALWAYS_USE = 3
See article Mission Editor: AI Tasking for more information on how AI tasking is handled within DCS.
En-route Tasks: engageTargets, engageTargetsInZone, engageGroup, engageUnit, awacs, tanker, ewr, FAC_engageGroup, FAC
Commands: script, setCallsign, setFrequency, switchWaypoint, stopRoute, switchAction, setInvisible, setImmortal, activateBeacon, deactivateBeacon, eplrs, start, transmitMessage, stopTransmission
Options: ROE, Reaction To Threat, Radar Using, Flare Using, Formation, RTB On Bingo, silence, Disperse on Attack, Alarm State, RTB on Out of Ammo, ECM Using, Prohibit AA, Prohibit Jettison, Prohibit Afterburner, Prohibit AG, Missile Attack Range, Prohibit WP Pass Report, Engage Air Weapons