Burl's aircraft battery

[astjp2]

Has anyone replaced the 25ah battery with a burls tray and sealed battery on the firewall? Man they have over 500 of the boxes out there on cessna's and cubs and the feds are sure giving me a hard time about mounting it on the firewall...Tim

[Hank Jarrett]

Re: Burl's aircraft battery

Unfortunately, Taylorcraft originally put the battery on the floor in the cockpit just in front of the seat on the 41. You may have someone who actually knows that (which I seriously doubt) or who thinks it goes in a tray behind the baggage sling like the later planes. Both the tray in back and the firewall (especially the firewall) are bad ideas. The biggest problem with batteries in the engine compartment seems to be with putting the voltage regulator somewhere else. The voltage regulator is supposed to be temperature compensated and lead acid batteries take different charge currents depending on the temperature. The worst case is when the voltage regulator is in the engine area and HOT while the battery is in the cabin and cool. The regulator thinks the battery is hot too and provides too much current, ruining the battery over time. The other way around it doesn't provide enough charge which can be just as bad. It is NEVER a good idea to keep a lead acid battery in a hot place since heat kills the life all by itself. The problem with behind the seat under the baggage sling is the acid fumes do a real number on the fabric and tubes back there and a tray for it needs to be engineered properly so you don't get a big lead and acid lump ripping through the cabin in an "arrival". Bolting down a battery isn't as simple as many think. It can easily kill you in an accident and if you go up-side-down with an unsealed battery you get acid poured all over everything to boot.
What I did on my 41 was make a battery box like the original and put a SEALED motorcycle battery in it with enough room left over for a charger (one of those you use for boat batteries that can be left hooked up forever) and a couple of 12V jacks. If you make it removable you should be able to convince your inspector it is not a permanent installation and isn't covered by his requirements. I actually don't put mine in the plane (not for years now anyway and the original wind generator is in a box in the hangar too) so he never even questions it. It is nice if I want to go cross country to keep the hand held and a GPS powered.
Hank