[aerohead]

I did some simplified 'pencil-whipping':
1) Same propeller
2) Same motor nacelle
3) 3.15:1 NAVY strut of approximately twice the thickness of the round tubing it replaces is the only variable
4) 7.5-MPH velocity submerged in 59-F water
5) Water density ( rho ) = 1.980874
6) @ 745.7-Watts / horsepower
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By exchanging the tubing for the 'thicker' strut, the electric load is reduced by approximately 160-W / hour, or, 21.3-W / mile.
---------------------------------------------------------------------------------------- The strut data was presented by Chief Aerodynamicist, Walter Korff, Lockheed Aircraft Company, as provided in the book, 'Airplane Design: Aerodynamics', by Edward F. Warner, 1927.