The Montanas

[Karl Heidenreich]

Bgile wrote in other thread:

The US Navy tried to protect their ships against a ship with similar armament. They knew that wasn't the case with the Iowa class, and the Montana class would have been a much better balanced ship. It would also have had better TDS because the internal belt was not a part of it. The machinery arrangement was much better for limiting torpedo damage as well. IMO was a far superior design. The Midway class carriers used the same machinery arrangement.

Ironically, the secondary battery wouldn't have been as good for AA defense as the 5"/38s on the Iowas because the 5"/54 mounts designed for them were cramped and had some of the same problems as the British 5.25" guns. They were not popular with the gunnery depts of the Midway class carriers, which is where they ended up after the Montanas were cancelled.

I believe that of all the "never built battleships (Super Yamatos, Saint Andrews Class, Montanas, H Class, etc.) " the Montanas were the ones closer to being a reality. After some examination I came to this particular doubt:
Why, if there was the chance to design and build a brand new Battleship, the USN insists in a 16" gun instead of a heavier one: 18" or 20". The Montana had the potential capability to mount either. ( The US had the material capability to build it and rearreange the Montana´s design) That and considering that an earlier enemy BB like Yamato already mount 18"main guns. Moreover the British were considering the mounting of 18" on the Saint Andrews Class (but I doubt that in 1945 they were going to be able to build and install it). And the Germans had this idea of bigger guns in their early H Class (aprox 16") but, if opportunity arrives, to build the bigger ones with the 20" guns. So, if the US had the opportunity to build the Montanas then, likely, Japan, Britain and Germany (well, strike the Germans out of this!) would be able to put at sea units with heavier and more powerfull guns. In theory any of those projected BBs were superior, in terms of armament, to the Montanas. And it´s funny because the US was the major power with more options to build the bigger one.

[Bgile]

The US Navy came to the conclusion that the 18" gun wasn't necessarily a practical solution. Here is the quote from the navweaps site concerning it's development:

BEGIN QUOTE of NAVWEAPS description of gun referred to variously as

18"/48 (45.7 cm) Mark 1
16"/56 (40.6 cm) Mark 4
18"/47 (45.7 cm) Mark "A"

These designations were all assigned to a single gun used for testing purposes between 1927 and 1945. In the early 1920s, the USN was in the process of developing the 18"/48 (45.7 cm) Mark 1 naval gun. The prototype for this weapon was about halfway completed when the Washington Naval Limitation Treaty of 1922 outlawed guns larger than 16" (40.6 cm). As a result of the treaty, the USN decided to complete the prototype as an extra-long 16" (40.6 cm) weapon. This conversion was performed by grinding down the muzzle end, re-threading the barrel to hold an extension ring and inserting a thicker, 16" (40.6 cm) diameter liner. The prototype was then designated as the 16"/56 (40.6 cm) Mark 4 high-velocity test gun. Proofing began at the Dahlgren proving ground in July 1927 and the gun was fired throughout the 1930s in various tests.

Battleship design studies conducted in 1927-28 and again in 1938 considered using the 18"/48 (45.7 cm) gun, but the USN rejected it both times for the following reasons: 1) Excessive weight, 2) Very short liner life, 3) Lack of sufficient angle of descent for all but very long ranges - i.e., little deck penetration capability. The use of this weapon would also have violated all of the Naval Limitation Treaties of the 1920s and 1930s, possibly the most important factor in its rejection.

Tests with this weapon in the 1920s and 1930s convinced BuOrd that standard 18" (45.7 cm) AP projectiles had only marginally better armor penetration than 16" (40.6 cm) shells. In addition, design studies showed that the same size battleship could carry a maximum of only six or seven 18" (45.7 cm) guns vs. nine 16" (40.6 cm) guns, even if the armor protection remained the same, as the 18" (45.7 cm) gun was a much heavier weapon. The larger gun would also have had a slower rate of fire, as the heavier shells required would have been more difficult to handle. These conclusions led to the development of "super-heavy" AP projectiles in the late 1930s, which made the US guns using them superior to other nation's weapons of the same caliber.

The start of World War II removed all treaty limitations and revived interest in larger caliber weapons. In 1941, the threaded tip was cut off and a new 18" (45.7 cm) liner installed. This weapon was then redesignated as the 18"/47 (45.7 cm) Mark "A" test gun and "super-heavy" 18" (45.7 cm) AP projectiles were designed for it. The gun was first test fired in this new configuration in February 1942 and a few more times until the end of the war. The eclipse of the battleship by carrier aircraft greatly reduced the Navy's interest in pursuing further development of large caliber weapons and the prototype was finally retired just after World War II. It is now on display at the Dahlgren Naval Weapons Facility in Virginia, USA, as shown in the photograph below.

Constructed of liner, A tube, jacket, nine hoops, six locking rings, a separate yoke ring and screw box liner. The breech mechanism was a down-swinging Welin block with vertical lever operating gear. Chromium plating of the bore was considered in the 1940s but never carried out.

END QUOTE

[Gary]

look what happened to the British.

The British 15" was a marvellous weapon in WW1.
The British then tried to go one better when they Built Nelson and Rodney but the 16" proved to be something of a dissappoint (compared with other navies).

The USN 16" 2700 lbs was a proven weapon, why change it?

I think that the USN had also realised that the sun was setting on the battleship era and that the Montana's would have been a waste of Money.

The proposed British Lion class which was never built was right after WW1 when the need for battleships was still evident.
The H-Class, Montana and "super" Yamato designs came some 20 odd years later by which time it was evident that the days of big guns ships ruling the waves was coming to a close.

[Coyote850]

Anyone have more info on the Saint Andrews Class? This is the first I have heard of it.

[Karl Heidenreich]

About the British Saint Andrew:

Displacement 49,000 tons
Armament 3 x 3 18"
MCG and AA

Speed 32 knots
VTS Rating 6 6 7

These fine warships, a prototype for the "fast battleships" of the late 1930's, were designed just after the end of WW I. The British "G 3 Battlecruiser" specification called for a long, fast ship with nine 16" guns, and "N 3 Battleship" called for a slower, shorter ship with nine 18" guns. Both their designs featured a concentration of the main armament to save armor coverage, which the British later took to heart in the Nelson class BB's and the French in their Dunkerque and Richelieu classes. As the Washington treaty took effect before these giants could be built, they never took to the seas unless you take into consideration their watered-down Nelson/Rodney progeny.

This is from http://www.CombinedFleet.com . I look for more information and there was none available. There is more for the Lion Class Battleships (9 x 16") in a KGV style warship.
Best regards.

[Coyote850]

Thank you Karl.

[Ramius]

I agree that the Montana's, if completed, should have had the 16in instead of new 18in ones. The 16in were proven to be very effective by the smaller Iowas. Building new 18in guns would have had taken more time and money to develop, and there is no gauranteeing that they would have been as effective as the 16in. I believe this was true for the Iowas vs the Yamatos, the Yamato's 18in were not as effective as the 16in, although that may have been because the Japanese shells sucked

[Tiornu]

Yamato's 18in were not as effective as the 16in, although that may have been because the Japanese shells sucked

I don't know what yardstick we could use to find Yamato's guns less effective than the American 16in guns.

[Ramius]

This yardstick:
http://www.combinedfleet.com/baddest.htm

[Bgile]

The 18.1" are clearly more powerful weapons ... the website just uses various fudge factors and ultimately says they are equal to the 16"/50 overall, not worse.

[Karl Heidenreich]

Yamato Class was the most powerfull and incredible BB killer ever built (not to mention the ugly CVs). At the thread about Yamato vs. Iowa it became quite clear that:
1. The Yamato´s 18" could hurt Iowa more and with more probability than the Iowa´s 16" could on the Yamato.
2. Yamato could withstand more punishment from Iowa´s 16" than Iowa from Yamato´s 18".
3. Yamato was meant to be the decisive weapon in the theoretical Jutland type Pacific Battle whilst Iowa was only a carrier escort.

No offense but this has been discussed a lot and Yamato appears at the end with an edge, even with the HOLY ARGUMENT that the RDFC would be crucial in such a combat.

[Tiornu]

Iowa was not only a carrier escort. She was a battleship designed for the same job every battleship was designed for.

[lwd]

.... Building new 18in guns would have had taken more time and money to develop, and there is no gauranteeing that they would have been as effective as the 16in....

The US had already developed and built at least 2 18" guns. So development time would likely not have been a constraint. The turrets might have been. From what I've read the US naval engineers had pretty much concluded that you reached a point of diminishing returns with 18" guns. Consider the Montana's as designed would probably only have carried 8 18" guns and if you are going to balance your design you need even more armor. The there are problems with the higher muzzle blast and shock. Now if they had been aware of the details of the Yamatos when they were designing the Montanas there might have been some reconsideration of some of this.

[Dave Saxton]

A few quotes from Malcolm Muir might help clarify a few things. These are in the context of the Iowas, not the Montanas, but it does shed some light on the thinking of the American designers of the time period:

" The General Board briefly considered three other guns. The 18"/48 with a projected projectile weight of 3,850 lb was rejected partially because only six could be mounted on a ship of the mandated size. The 16"/56 offered little advantage over the 16"/50 other than range, and suffered excessive barrel wear. The 16"/45 while the lightest gun under study didn't have as much range as the Navy wanted. (See Apendix B)"

"..thus when the Navy came to design it's next battleships, the Montana Class, it kept the 16"/50 and simply added one more turret. These very large ships of ( at least, DS) 60,000 tons were intended to resist the 16" shell, but planners found it extremely difficult, even with 15,000 additional tons, to make the ship proof against the 16"/50. At a General board meeting in the summer of 1939, two officers were discussing the relative merits of the 16-inch vs the 18-inch gun:

'Admrial Greenslade: Inasmuch as we are finding it almost impossible to protect our ships against the 16"/50, what enemy could put 18-inch guns on a ship and protect it?

Admiral Furlong: They could not protect it against our 16"/50. ' "

Regarding intended missions for the Iowas:

" These missions included dealing with enemy battlecruisers (the Kongos) detached from the Japanese battle line. The Iowas would also be perfectly suited for chasing down enemy heavy units operating, as the German ships would later do, against trade routes. On the other side of the coin the General Board envisioned the Iowas acting as raiders themselves, or more presciently, combining with other ship types to form a striking force -in later parlance a 'task group'.... Some popular naval authors wrote in the 60 and 70's that the Iowas had been designed specifically to protect fast carriers. Such reasoning is 'post ergo propter hoc'...."

Some things that Muir is revealing, as I read it; is that the Iowas were originally designed for tasks more in line with that of a large, but more modern, battlecruiser, and the later Montanas were to be the more traditional ships of the line. Additionally, they were more than satisfied with the 16" guns. This not only means that the 16" was probably enough deal with a Yamato, but that given the Iowas were not really meant to deal with higher velocity 16" guns themselves, they were even less capable of taking 18" hits- at any range.

The Montanas could of been equipped with 8-18"/48's, but the General Board considered that it would be impossible to come up with a balanced design, and I tend to agree.

Offensively, an even heavier projectile, such as 3,850 lb, may have been deemed counter productive at realistic battle ranges, as it would take longer before it would begin to attain steeper angles of fall. The angle of fall dynamics are more important than the weight. This was probably one reason why the IJN 18.1"/45 was a moderate velocity peice.

[Karl Heidenreich]

Hi Dave,

As always your interventions bring forth a lot of light to the discussion or topic at hand. Thanks for your quotes.

It seems funny that the Montanas were, hypothetically speaking, NOT the definitve weapon to counter the Yamatos (the US already did had that weapon in the form of CV and aircraft but not in the shape of an equal surface combat vessel). The certainity of the USN that the future of naval warfare was at the CVs hands must have made look for a diferent kind of BB in the way of a secondary class unit, an escort but not a BB Killer.

Best regards.