Sanity checking power calculations: Lion class battlecruisers

As an experiment, I estimated values for the Lion class battlecruisers to see what sort of power that would be calculated for 27 knots. The answer is that my program came up with the following results for the parameters that I used:

• displacement: 26,779 tons
• dimensions: 700ft x 88.5ft x 28.6ft
• Cp: 0.575
• Cm: 0.92
• propulsive efficiency: 0.49
• speed: 27 knots
• SHP: 69,184.4
• residual EHP: 12,831.7
• frictional EHP: 21,068.7
• speed-length ratio: 1.0205

I thought that this was reasonable result, given the inherent sloppiness of the program vis-a-vis hand calculations where I looked up exact Cr values from The Speed and Power of Ships.