[quote=Bill_H;650880]This is going to be a great thread!
Did you consider an external alternator driven from the accessory pad on the back of the gearbox? Like this 20amp $700 example?
(I have NO IDEA if it would actually "fit" given the other stuff on the top of the engine.)
For reference purposes:
Regarding the new Rotax fuel-injected engine electrical system - this is from the ROTAX manual on it.
Two alternators are built into the stator.
Alternator A is only used for electronic engine components (ignition, injection, and sensors).
Alternator B is used primarily to start the engine and charge the aircraft battery.
While the engine is running, Alternator B can be used for the on-board instruments.
Alternator A 14V/16A (220 watts nominal)
Alternator B 14V/30A (420 watts nominal)
If Alternator A fails, Alternator B takes over its functions. This means that the bettery will no longer be charged and no voltage will be available for the on-board instruments.
Besides these an optional external alternator is also available:
"600 watts DC at 6000 rpm"
"14.2 V to 14.8 V"
It appears to be about 40 amps at 4000 engine rpm.
Note that the engine has TWO electric-driven fuel pumps.
These are listed as "optional" and are listed as 10 amps each (in one place) but 10 amps total (in another place). Confusing.
And, they supply at 65 psi. This optional assembly is recommended to be installed under the fuel tank, with an upstream filter and water trap.
Somewhere in this forum on MUCH earlier postings there is a picture of a Rotax 912 with an Alternator fitted to the accessory pad .... do a search to find it!