Ultra Stick 60 and 9C radio
Jason - you don't need additional channels to plug in another battery. You can use a Y harness to plug in an additional battery pack and switch. I do this on each of my 1/4 scale planes - two battery packs, and two switches - both on all time the plane is flown. I don't do this to extend the flight times, since I use 1650ma NiMH battery packs, but for the redundency in case there is a problem with one pack, wiring or switch.