Why don't heatseekers lock on to low flying vehicles?
Whenever I try to lock on to a low-flying attack or scout helicopter with heatseekers, it doesn't work. I know in Battlefield 3 there was an upgrade called "Below Radar" which gave helicopters this property. However, I haven't seen this ability in the Battlefied 4 progression for any air vehicles. Is this upgrade just given for free to all players?
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