FYI: tracking darts turn RPG and Gustav rockets into guided missiles.  So if you can hit a helicopter with a tracking dart, do it.

did you just learn this?

What did you think they were beforehand might I ask?

Yeah I abuse the tracking dart, unfortunately there's never a rocket launcher guy around when I need one.  It's not that easy to hit a chopper though, I've tried many times.

Lol ya, I shot an RPG at a helicopter, thought I had missed then it took a mean turn and boom.  I thought it was a (pretty awesome) glitch then I took the time to read about the darts.  Prior to this I thought they were just for keeping track of vehicles, e.g. making sure a tank doesn't roll up without some kind of warning.

" @Hitchenson: I thought they were for decorating snipers sitting on your hill. "

" Lol ya, I shot an RPG at a helicopter, thought I had missed then it took a mean turn and boom.  I thought it was a (pretty awesome) glitch then I took the time to read about the darts.  Prior to this I thought they were just for keeping track of vehicles, e.g. making sure a tank doesn't roll up without some kind of warning. "

Yeah I thought the darts were just for permanently marking vehicles too. 
 
Good to know!

Not permanently but longer than just spotting. I think they mark for about 30 seconds or a minute.
 
But don't shoot the RPG until the distance appears below the orange square. You aren't locked on until it appears. Then it will definitly hit the chopper (if it doesnt fly into something) and RPGs are a 1hitkil for any Chopper.

" Not permanently but longer than just spotting. I think they mark for about 30 seconds or a minute.  But don't shoot the RPG until the distance appears below the orange square. You aren't locked on until it appears. Then it will definitly hit the chopper (if it doesnt fly into something) and RPGs are a 1hitkil for any Chopper. "

is there any way to know it locked on or does it automatically do it?

Hey! Your the guy I hate when he is on my team :(
 
@Tuggah said:

" is there any way to know it locked on or does it automatically do it? "

" @heatDrive88: Pretty sure they do, but I have only shot two down and they may have been damaged already. "

I always manage to forget that I have Tracer Dart when I carry it and end up shooting people with it thinking its a pistol when i run out of ammo while using Engineer Class lol.

In Soviet Russia, Darts track you! 
 
but I've never used them for that and that makes sense... I'll give it a shot next time I play.

The best part is that you can actually hit people with them. I've been sniping snipers with tracer darts since the demo and there is nothing more satisfying than seeing your guided missile explode in their faces.

I would never, ever replace my awesome Magnum Revolver with that stupid tracer gun. I love my wheel gun too damn much.