Quick rundown on technical details:
UDP is a fire-and-forget protocol of sending data. There are no guarantees that a packet will reach its destination.
TCP is a send-and-wait-for-ack protocol. You send a packet out, the server replies to tell you that it has received it.
In Aces High, if the server does not detect any UDP traffic for a period of 8 seconds consecutively, it switches protocols to TCP.
The problem is packet loss between your computer and the AH servers. Download
Ping Plotter and run it to trace the route between you and AH. You'll see where the problem lies.