Luke,

Great question! This will take some digging. None of my otherwise informative and reliable references give a number. However, in the meantime lets assume that for stability reasons the amount of ammo carried is fixed by weight. The 5"/25 round weighed 75 lbs each. 75 of these shells come out to 5625 lbs. The 4"/50 round weighed 65 lbs and the 3"/50 round 25 lbs. Doing the math this comes out at 86 rounds for the 4"/50 and 225 rounds of 3"/50. These numbers are probably not overly accurate, but it gives us something to start with.

I will let you know what I come up with.

Thanks, Dave. :)

I've another question for you (and I think this one is a bit easier ;)): how many men at a time would stand watch in each diesel compartment?

Master Chief & Senior Chief ranks...
 

just curious as to why the designers put them in the game when they didn't exist until 1958... Chief was the top of the the enlisted structure until then...

David
Los Angeles
Nuc Waste 1984-1987
Subase Pearl Harbor Radcon

Check out post 183 in this thread. :)

I can't really answer that, it is obviously a mistake on the programmers part. However, I am actually impressed with all the things they got right, especially in some of the exterior details on the boats. Not perfect, but pretty darn good. :up:

Aha! Yes, now I remember that question came up before. :D

Dave,

In response to your post above:

In looking through many fleet submarine crew rosters it, seems that the typical number of machinists/firemen per sub was 21-22. Now, here's my dilemma: looking at the initial roster for a boat sailing in June 1944 (USS Icefish), the following machinists/firemen are listed:

• 2 Chief Motor Macs
• 4 First Class Motor Macs
• 5 Second Class Motor Macs
• 3 Third Class Motor Macs
• 7 Firemen First Class

(Interestingly, there was not a Third Class rate for machinists until 1944; until then, that billet was filled by Firemen 1st Class).

That's a total of 21 altogether. Now, assuming a total of 6 men will be on duty in the control room, that leaves 15 men for the diesels. Assuming, then, that 5 men at a time will be detailed for a diesel compartment watch, it would seem to me that one senior petty officer plus an assistant would be on watch in each compartment. Hence, that would leave 3 men to be in charge of both compartments per shift. Put another way:

Air Manifold: 3 men
Trim/Drain Manifold: 3 men
Fore Diesel Compartment: 6 men
Aft Diesel Compartment: 6 men
Senior Diesel Petty Officers: 3 men

That's about the only way I can figure that's how the watches worked. However, there's also this line from the Fleet Sub Manual on diving operations:

If that means that there were, say, only 1 man regularly on watch at the air manifold, then each diesel watch could have 1 senior petty officer plus 2 assistants. Or, am I reading this wrong? Were both manifolds manned at all times?

Hopefully I've not muddied the waters here too much. :D

Luke,

Great info and some good detective work!

Here are some inputs:

Firemen are considered to be "non-rated", i.e. they do not have a specific job classification and can be assigned to any of the engineering divisions. Some of the Firemen listed may have been assigned to the Electrical Division (E-Div), some to Main Propulsion (M-Div), and some to Auxiliaries Division (A-Div). Those assigned to E-Div would have stood watch in the Maneuvering Room at the cubicle and would have been busy taking gravity readings in the battery well, lining up for battery charges, etc. Being non-rated, it also would not have been uncommon to see a Fireman standing watch in the control room at the dive planes, helm, and lookouts or even loaned out to the torpedo rooms or gun teams as hired muscle.

The air manifold and trim & drain manifold would only have had one sailor standing watch each and these men would have been assigned to A-Div.

Once the war started, rigid adherence to the peacetime manning and organizational documents kind of went by the wayside. We had manpower to spare and the boat CO's were given a fairly high degree of latitude to organize their watch sections as they saw fit. As long as the CO could demonstrate that he could effectively and safely fight his ship, he could pretty much do as he pleased when it came to organization.

Given the rapid pace of the war and the excess of manpower, it was extraordinarily difficult for the Bureau of Personnel to precisely adhere to the manning documents and regulate what rates and how many of each rate were assigned to each boat. This would account for the variations that you are seeing in the crew rosters.

You are making an admirable and concerted effort to ensure that your RFB crew rosters are as accurate as possible. I applaud your efforts. Unfortunately, given what I said above, I think you may want to generalize, have it make sense, and move on.

Thanks for your hard work on the mods!:yeah:

Dave,

You're absolutely right. I've had to make a few concessions to the crew lineups, based on what the SH4 engine allows. One of the biggest of these is the fact that the maneuvering and diesel compartments are not separate, so I've had to lump together all the machinists and electricians together into one compartment with one rating. I would love to have more fidelity with how the ratings and compartments are divided up, but it just can't be done.

A couple more questions for you:

• Who else besides radiomen would be trained to operate the radar equipment?
• What types of duties did Signalmen have on submarines?

The rate of Radarman (RD or sometimes RdM) was established in 1942. This would have been the primary source for radar operators. However, in a situation similar to sonar operators, because this was fairly new technology and few people had proper training in it most captains would send just about anyone in the crew who showed an aptitude for electronics to radar school. Along with the Radiomen, it would not have been uncommon to see Yeoman, Ship's Cooks, Quartermasters, or non-rated Seamen operating the radar. Once sufficient numbers of RD's starting showing up, they would have taken over this duty.

Like their surface ship brethren, Signalmen (SM) on submarines would have been responsible for all non-radio based communications, i.e. semaphore, blinker light, and signal flags. However, since submarines operated mostly independently and submerged a lot of the time, SM's had precious little rate specific jobs to do. Their normal underway watch station probably would have been helm/planes/lookout and would have been additionally tagged for gun and ammo handling details and may have helped the Torpedomen in handling and loading torpedoes.

Gun Ammo
 

As far as the gun ammo loadout issue, I have been completely stymied in finding this information. None of my normal contacts can provide a number. Probably the reason behind this was that it varied so much from patrol to patrol and from boat to boat. As the war progressed, many additional ammo storage tubs were added topside to hold ready service ammo. The numbers and sizes of these tubs were limited only by the creativity of the boat crews and the yard workers installing them, with stability concerns factored in. This situation alone would have greatly varied the ammo loadout. In addition, the configuration of the ammo magazine under crew's mess was probably tinkered with often by the yard crews in an attempt to pack in as much ammo as stability would allow.

With all this in mind, there probably isn't a "typical" amount of ammo carried. To get what the as-designed loadout was, you would probably have to refer to the original design prints stored in the National Archives.

However, for game programming purposes the numbers that I cited above would be a good starting point. An educated guess would be that 225 rounds of 3"/50 is probably on the high side. 175 would be a more reasonable number. The numbers for 4"/50 and 5"/25 are probably pretty close.

That's about what I thought and along the lines of what I've read. The only thing is that, as far as my research goes, it was very rare to see the Radarman rate on board a submarine (I think I've seen only one or two examples of a boat with a Radarman-rated petty officer). More commonly, it seems, a single petty officer with the rate of Radio Technician would be included among the sub's complement, and he would be the one in charge of radar equipment.

In other words, "all other jobs as required." :D

That's probably about right. I've done some calculations from patrol reports that detail the amount of ammo expended, and those numbers seem about right, though like you mention, the numbers can and do vary greatly from boat to boat.

Interestingly, for comparison, is the amount of German 105mm rounds stored in a Type IX U-boat. A post-war study found that the boat was designed to hold 250(!) rounds. I would be curious to find an example of a fleet sub that carried a comparable amount of 4" ammo. That seems like an awful lot of large-caliber ammo for one boat to carry.

Dave,

What types of parameters were used to record how fast a boat could dive? That is, I'm looking for the following info:

• Speed at start of dive
• Depth at which dive time stops

The only hint I have at this point is that, in the ONI manual on U-boats, the dive times are listed as "Crash Diving Time to Periscope Depth."

Diving times were usually measured under the following parameters: boat fully surfaced and running at a standard bell (approx. 15 knots), and time to get to periscope depth. For the Gato/Balao/Tench classes PD was 65 feet. At the start of the war the fleet boats were credited with 50 second dive times. By the end of the war that was down to an average of 40 seconds. With a lot of training some boats were able to dive in 30 seconds. For a boat the size of the fleet boats this was pretty impressive.