Matty,

I was just asking about a battery back-up system on another post and STLPilot gave me the best answer I have seen so far. Here is the RCU thread if you are interested.

http://www.rcuniverse.com/showthread...7&pagenumber=6

He provides pictures of the installation and provides good information insight regarding using a Y-harness for a servo and battery back-up. It's called the battery backer put out out by

http://www.emsjomar.com

I ordered one myself for a Da 50 going into a Pitts. I haven't tried it yet, but it sure seems like the right fix to answer your question. STLPilot uses it and is convinced this is the ticket..