User blog comment:DaveyDave/Tracer Dart Question/@comment-1684663-20100410045800

Rank up your vehicle unlocks. It will be Vehicle Alternate Weapon Package. The one with the 3 bullets stacked on top of each other. The tracer dart on the attack helicopters is ONLY on the gunner that is the 2nd seat. The tracer will be hard to see since you are viewing in black and white but if you do it correctly on an enemy vehicle it will report tracer dart plant +20 or something like that. You can also hear it fire. It's a very soft Pfft.