I was wondering if anybody out there has built an Aircam with Rotax 914 engines, and if so, if anybody has wired in a redundant back up electrical source for the dual electric fuel pumps.
Since there are no engine driven fuel pumps on a 914. Has anybody wired in back up batteries to keep the fuel pumps alive.
The reason I am asking, is that we had another aircraft with a 914 on it. We also had a lithium battery for the main and only battery on board. The lithium battery had a thermal meltdown in flight and completely shorted the electrical system. Therefore we had no electical power to run the fuel pumps. As a result of no electrical power to run the pumps, we had an engine stoppage. Luckily an airport was directly below and a safe landing was made.
We do not plan on putting lithium batteries back into an airplane ever again. Because a 914 requires electrical power of some sort to stay running, and we know the chances of a twin engine aircraft losing both stator charging systems, and both external alternators, and the battery failing are slim to none, we want a backup electrical source to run our pumps.
Instead of re-inventing the wheel and engineering this feature into our electrical system, I was wondering if somebody already has done this type of thing??