RE: question about need for regulator
There can be a problem using NiCad or NMIH batteries and the newer digital receivers and servos.
Under significant momentary loads (from servos, electric retracts, etc.) The NiCad and NMIH batteries can decrease in voltage,
even enough to cause the digital receiver to reset, go to defaults, or just momentarily hold.
The actual current for this to happen with the common AA cells is somewhere around 2A.
We tested some or the larger E-Flite electric retracts, rated at 900Ma, and found peak currents around twice the rating.
With a less than fully charged 2000NMIH pack, the momentary voltage drop was enough to cause the retracts to hang, get out of sync from one to the other, or just not operate. The retracts have an odd shaped cam slot, and the peak current occurs as a brass "T" cylinder goes over the sharp "hump" in the slot. Many digital servos may draw a momentary current (per servo) of up to about 1-1/2 A.
Lesson learned was to use a 5-6A, 5 to 6v regulator on a LiPo battery to insure sufficient available current.
With electric retracts, think about using a separate power source or regulator.