Hi Keith,

Plumbing 2 fuel cells to an UAT can be done in series or parallel. We have done both with no problem.

Parallel works well with 2 cells on either side of the airplane, fuel will be drawn evenly resulting in good balance. Series work well with tanks forward or aft of one another. Fuel can be drawn from aft fuel cell first to minimize CG shifting condition (more importantly if the CG moves aft).

Regards,
Kraivuth S.