Superfast light battlecruiser

I did a design for what was intended to be a "super fast" light battlecruiser with 4-17in/45 (138.6 tons) and 16-4in/50 QF (2.2 tons) guns. I did somethings to drastically reduce hull weight, but using a low hull depth design. The specs were:

• light displacement: 32,000 tons
• normal displacement: 33,500 tons
• dimensions: 800ft x 85ft x 29.7ft (45ft hull depth)
• armament: 4-17in/45 and 16-4in/50 QF
• Cp: 0.60
• Cm: 0.97
• hull weight: 8,890 tons
• machinery: 12,750 tons
• auxiliary machinery: 1,232 tons
• armament: 2,088 tons
• protection: 4,480 tons
• miscellaneous: 2,560 tons
• machinery weight basis: 40 SHP/ton of machinery (too high)
• machinery: 510,000 SHP (probably wildly overoptimistic)

The fundamental problem with this ship is now to deliver that much power. Frank Fox has spoken to me about a fundamental limit of about 70,000 SHP per shaft, before the shaft would give way. It might actually be slightly higher, but not with 1921 technology.

Another factor is the shallow draft, which also complicates shafting, along with the narrow beam.