RE: 6V battery and no regulator??
I also have been using unregulated 5 cell Nicad Rx packs in all my planes for the past 10 years. In my jets I use 1700 mah packs and recharge after 3 flights. That's not a problem for me since I always take 2 or 3 planes to the field and rarely put more than 3 flights per day on any one.
Joe