Naval History Forums

What if someone had given or sold plans of the Yamato class to US intelligence during 1938? How would US ship building or war plans have altered? Would a Montana-like design have been built instead of the Iowas?

Then the US woiuld have proof that the Japanese were violating the Washington Naval Treaties that they had signed up to along with the US. They would then regard the treaty provisions as null and void insofar as their battleship construction was concerned, as well as take strong economic sanctions against Japan until they desisted from their plans. The Yamato plans, coming at around the same time as the Panay incident, would be seen as a direct threat to the US.

RF wrote:Then the US woiuld have proof that the Japanese were violating the Washington Naval Treaties that they had signed up to along with the US. They would then regard the treaty provisions as null and void insofar as their battleship construction was concerned, ....

Except at least according to:
http://en.wikipedia.org/wiki/Washington_Naval_Treaty

...renunciation of the Naval Limitation Treaties in 1936....

As I recall that's what triggered the US to use the escalater clause to arm the first fast BBs with 16" guns.

Having the plans for the Yamato in 38 might speed up the Montanas and result in the US reassesing it's 18" gun.

That last sentence is interesting.......if it had led to that 18 inch gun being tested in battle, on a one to one basis vs Yamato....

The USN 18" gun was a 18"/48. There was also a 16"/56 gun but it was not as well liked as the 16"/50 because of greater bore errosion. It did offer greater range.

As I recall G&D mention that an alternative setup for Montana at one stage was 8-18" guns in twins, rather than 12-16"/50s in triples. This scenario begs the question if the Montanas design would be turned to though. The Americans realized that their own designs would have little if any IZ vs their own guns. It was reasoned that if the USN could not build an AoN design capable of withstanding their own guns, then neither could anybody else. Knowlege of a Yamato throws a monkey wrench into the planning.

They may have taken the course that if the guns could likely over power the armor anyway, then why not build lightly built but heavilly armed BCs with high speed? Or do they take the opposite course of a rather slow BB with massive armour?

My understanding was that the muzzle blast associated with the 18" guns was also a concern. It was getting to the point that it could damage some of the ships supersturcture and was a source of potential danger to crew on deck.

Dave Saxton wrote:The USN 18" gun was a 18"/48. There was also a 16"/56 gun but it was not as well liked as the 16"/50 because of greater bore errosion. It did offer greater range.

As I recall G&D mention that an alternative setup for Montana at one stage was 8-18" guns in twins, rather than 12-16"/50s in triples. This scenario begs the question if the Montanas design would be turned to though. The Americans realized that their own designs would have little if any IZ vs their own guns. It was reasoned that if the USN could not build an AoN design capable of withstanding their own guns, then neither could anybody else. Knowlege of a Yamato throws a monkey wrench into the planning.

They may have taken the course that if the guns could likely over power the armor anyway, then why not build lightly built but heavilly armed BCs with high speed? Or do they take the opposite course of a rather slow BB with massive armour?

Montana would have been the first US battleship with 16"/50 guns and a realistic immune zone against them. This did come at the cost of maximum speed compared to the Iowas, and of course she was larger as well.

I suppose had the Yamato's details been known early enough, the USN might have relaxed the criteria that new construction ships had to be able to transit the Panama Canal earlier than they in fact did. It is possible therefore that designers might have been given more of a free hand with the result that the Iowas might have emerged from the yards more heavily armed and armoured than they in fact were.

Essentially a jump directly to the Montana's? or something else?
Looks like the North Carolina's were authorized in 37 so construction on them probably go's ahead as scheduled. The SoDak's weren't laid down until 39 though so there status becomes unclear.

tommy303 wrote:I suppose had the Yamato's details been known early enough, the USN might have relaxed the criteria that new construction ships had to be able to transit the Panama Canal earlier than they in fact did. It is possible therefore that designers might have been given more of a free hand with the result that the Iowas might have emerged from the yards more heavily armed and armoured than they in fact were.

If the threat is Japan - then presumably these monster ships would not be needed in the Atlantic, so once sailed into the Pacific the long way round they won't be called upon to make a return journey.....

No need to change anything based upon the thread scenario; the Yamato wasn't significantly better than the fast battleships, and ten of them trumped two or three Yamotos, anyhow...

tommy303:

I suppose had the Yamato's details been known early enough, the USN might have relaxed the criteria that new construction ships had to be able to transit the Panama Canal earlier than they in fact did. It is possible therefore that designers might have been given more of a free hand with the result that the Iowas might have emerged from the yards more heavily armed and armoured than they in fact were.

I do concur with this reasoning.


yellowtail3:

No need to change anything based upon the thread scenario; the Yamato wasn't significantly better than the fast battleships, and ten of them trumped two or three Yamotos, anyhow...

Several things must be analysed here:

1. That can be said today because we know a lot of things the guys in WWII do not know. Simply put, under such an information the USA cannot play it conservative and will react in order to superseed the menace. In that case, as lwd, pointed out we know FOR SURE, that the USN will produce their North Carolina vessels, which are good vessels but will not be regarded as a match for the Yamato.

2. South Dak´s had a great chance not to be built at all. Maybe not even the Iowas.

3. A new class of American SuperBattlehip will be brought to the oceans. 12 x 16" or 8 x 18". We do not know. But no military will sleep confortably knowing that, maybe, the enemy has something more powefull in the oven.

4. You already know I do not concur with the idea that the USN had a match for the Yamato, which calls for an escalation in the size of the ship.

Best regards,

Perhaps some of these designs may have become realities?

http://www.wolfsshipyard.mystarship.com ... united.htm

One or two of them are products of a diseased mind I think

Nice link Gary ! ! !

Sort of " Warship design by Collage " technique -

Going to his main website I found stuff on there for other navies too , some of it quite plausible and cleverly "scenario-ed"
but as you say , some wildly impractical and pretty obviously cut and pasted together .

You can see why the worlds leading Naval powers , confronted with these sort of giant wish-lists as imperative and immediate requirements by their Admiralties said " B****r that ! " and got together to agree the Washington Treaty Limits instead , cant you . -- my God , the money that would be needed to make one , let alone run it !

Gary,

Incredible! There are some amazing designs there. The one with sextuplets 16" turrets is really something! Can you imagine the blast and concussion of the guns of such a thing?

Warmest regards and happy birthday, by the way!

Karl