- Location
- Arizona
While bulbous bow designs were old hat by that time--even US pre-dreadnoughts had them, and they were often known as "Atlantic bows" in ship design at the time--the Yamato class did pioneer the modern projecting bulbous bow. (US pre-dreads retained their ram bows for hydrodynamic reasons even long after ramming ceased to be a realistic tactical option; they actually made what's called a "plow bow" that was sort of similar to a projecting bulbous bow, but it was dropped in favor of a straight bulb around the time that we started building dreadnoughts.) While a straight bulbous bow does reduce drag nicely (through some black magic involving changing the wave pattern on the bow), extending it past the stem is even more effective (through further black magic involving interference patterns between the bulb's wake waves and the stem's wake waves almost completely cancelling each other out that just doesn't make any sense to me from a physics standpoint). Thus, the Yams did provide us with one great legacy in naval architecture that is used on virtually all large ships today.
Who's the one on the left supposed to be? SoDak?
One thing to point out, that advantage of the projecting bulbous bow only exists in perfectly calm water, once you start getting chop and wave action the advantages start to vanish quickly according to the latest hydrodynamics modelling and research. The USS Texas hull form is actually *more* efficient in typical Atlantic conditions than the modern super-bulbous prow because the smaller, less projecting bulb isn't as badly affected by the surface wave action.
Basically if I'm understanding it correctly, the problem is that the bow wave generated by the bulbous bow which produces the 'calm' through which the rest of the hull sails thus reducing friction can 'detach' from the hull in even moderate chop, and the further away the wave is generated the lower the required sea state for this separation is. With the modest bulb of the US dreadnought form the bow wave stays attached even up to fairly heavy seas, while the massive projecting bulb of modern usage gets disrupted in even relatively light seas.