Sonerai I Battery Placement

[Kevin]

Where are folks putting the batteries in Sonerai I's?? Near the firewall, in front of the seat or behind the seat somewhere??

I will probably use a 2180cc engine and am trying to make a best guess to accomodate a good CG. My weight will be around 165 lbs.

Thanks

[juergen]

Hi Kevin,
all Sonerais are different, but I think, if your Sonerai is near mine, the best place shall be before the Firewall on top, there is enough room.
with best regards
Juergen

[Kevin]

Thanks Juergen,

I am fairly new at this and don't know how your machine is configured. Is it a S-I, what size engine, starter and your weight?? If you know off hand, what is the length of your motor mount, probably around 8.5 inches?? I assume your CG worked out okay??

I am just trying to get things placed to avoid having to put in ballast later to balance it all out. I would guess a 2180cc engine weighs a little bit more than a smaller one. I would like to use a starter, so that is another 5 pounds or so firewall forward.

I was thinking; guessing; the battery would go up against the firewall on the aft side since I was using the larger engine and a starter.

Sounds like for sure I don't want to put it behind the seat.

Thanks again,
Kevin

[thepelican]

Kevin:

I am preparing an S1 for flight after having owned it for 4 years. My aircraft was built by Carl Baker of Oklahoma City. He placed an aluminum battery box behind the pilot seat on aircraft right attached to the lower right longeron, cross brace to the opposite longeron and cross tube under/behind the pilot seat. My S1 has a permanent magnet alternator, rectifier/regulator, starter, inverted starter solenoid, fused primary bus, master solenoid, ammeter and single Slick magneto. The battery box is sized for a motorcycle battery and vented. The electrical systems only consumers are the starter and battery. I am leaving it all in place since I am not fond of hand propping to start the engine. I have his weight and balance material but haven't looked closely at the numbers for the CG yet.

Regards,

Russell Johnson

[Kevin]

Thanks Russell,

Another data point.

Where are you located?

Kevin

[thepelican]

Kevin:

Newark, DE; Airplane is in my garage, probably 'til late winter.

Russell

[juergen]

Hi Kevin,
give me your mail adress as PM and I will send you my W&B spread sheet, so you see more and you can calculate difference positions (if you can handle this kind of programs )
My S1 have 500lbs empty and 750lbs cross, 2180cc engine...
with best regards
Juergen
(next 7 days I am out of office, so it take some time...)

[Kevin]

Juergen, thank you very much. The CG info will be most helpful now and in the future. It sounds like your machine and mine are very close as far as the configuration and engine are concerned, and probably the weight too.

My email address is [e-mail]

Kevin