ORIGINAL: rctom
Plus I'm using two Ni-MH, 6v, 2600 mAh, sub c batteries, plus one Ni-MH, 4.8v, 2600 mAh, sub c battery for the ignition.
Why do you want to use such heavy batteries. You can get Sanyo 2500mah AA size cells and save half the weight and half the cost (though it's too late for you to save any money). 3 5 cell packs like you have weighs 30 ounces (2 oz. per cell, 14 cells).
Use these smaller packs (virtually the same capacity) and save a full pound.
TF
The major problem with the little AA size batteries is internal resistance. All the Sanyo HR-3U batteries have a internal resistance of 25 mOhm which is way too high for use in an aircraft using 9 digital servos. The problem that can and will occur is total shut-down of the pack. If you put enough draw on the pack and exceed its limit no power will flow. The larger sub-c batteries, Sanyo HR-SC 2600 mAh which are "high capacity", and have only a 4 mOhm resistance which is lower than most Ni-Cd batteries.
The only thing that I personally would use the HR-3U batteries for is a transmitter. The high resistance would not matter because of the low draw of a transmitter. There are suitable application for all size batteries. High capacity, high resistance AA batteries will never make their way into any of my aircraft.
I suggest you check with Red Scholefield in "The Battery Clinic" before you use the HR-3U batteries in any R/C aircraft.