This is probably the fastest way to get supplies, but I find the helo's don't always fly away afterwards.

They kind just sit around taking up space :\

Just thought I'd mention.

I have experience that lot of such problems are comes from poor server FPS which is giving scripts lag.

Ah ok. I am going to work on a dedicated server (my old pc) today so hopefully that will fix it.

Well in fact it does. They act pretty erratically.

Due to having to deal with a lot of other issues for my new mission, I made a server out of my old PC. 6 core AMD with 8gig ram, now running linux and only the server.

As you can imagine it's fairly fast (a lot faster than running windows).

So with just me on it from LAN I had one heli hover for 20 minutes before finally leaving, the other dropped off 1 guy then proceeded to take off straight away - letting the other 3 guys fall out one at a time, the last one dying ;)

I have server with Xeon core4 and i still can overload the server . It depends from your mission setup.
Check your server FPS using admin command #monitor 10.

roger.