re: Sig Senorita. AGAIN!

I believe that the main issue will be the battery compartment. I recently built a Kadetito from scratch, which is basically a scaled version of Kadet Senior or Seniorita. There is enough room for a battery, but you want to place it right behind the firewall to keep the CG.

You might want to open a bigger hole in one of the fuselage formers so that the battery goes through it. That is much easier to do before you glue the former in place.

Best regards,

- Angel

On Thu, 12 Jun 2008 16:03:39 -0700 (PDT), Mikie wrote in :

Yes.

As best you can, build up a little box off the firewall (strongly attached!) on which to mount your electric engine so that the prop comes out where the gas prop would be. Try to get the thruslines right, too (any downthrust, any right thrust).

Then you need to find out where to carry the batteries so that the CG is correct.

Then you build a battery box and hatch system. MAKE SURE THAT THE BATTERIES CAN'T FALL OUT AND GET DISCONNECTED. This happens all the time with homebrew systems. The results, I hear, are generally not pretty.

You also need cooling air to flow over the batteries. The key is to have much larger exit holes than entrance holes. I forget the factor--twice as large? Three times?

Cool air comes in, picks up heat from the batteries, and then needs extra large openings to exit. Or something like that.

Let us know how it turns out.

There are lots of people who have done this already, of course. I'm not one of them. If you poke around, you may find a site that walks you through the whole process.

Marty

All good advice. Very good advice.

Yea verily on the cooling air. When you first fly, test the cooling by making some short, high-power flights, then land and _immediately_ check the temperature of the batteries and motor. They should not be too hot.

Then make longer high-power flights, and check again.

Once you can fly for a few intense minutes without overheating anything, relax and enjoy the plane.