The Ship Model Forum

I looked at Norman Friedman's "US Cruisers" and it has no photos of the USS Pittsburg.

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A collision at sea will ruin your entire day. Aristotle

Have you seen this one from the NHHC? https://www.history.navy.mil/content/hi ... 50353.html

Navsource's page has the same one but at a much lower resolution. I cropped into the stern for you - lots of sailors, but at least you can make out what seems to be deckedge netting. No helopad, just the hangar cover and a boat outboard of it.

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De quoi s'agit-il?

First off, the BALTIMORE class cruisers didn't have a "dedicated" helo pad in the 1950's. The helicopter just landed in the area between the #3 turret and the hangar hatch. In the late 1950's they started to paint a landing "target" in that area. Second, USS PITTSBURGH (CA-72) was decommissioned in 1956. So, the two overall images below taken in November 1955, shows her last configuration before being placed in mothballs.

In the overhead shot, you can see that she didn't have a landing spot marked out on the wood deck and that the elevator hatch is closed. When the hatch was opened, it slid forward and covered the landing spot. Between these two views, you can see her configuration in 1955, armament (ten twin 3-in RFG mounts) and radar suite.

In the two crop views showing just the stern area, the first one is from the same overhead image above and the second image was taken in 1952, before her 40-mm guns were removed and replaced with twin 3-in RFG mounts, shows a large helicopter that has landed on her deck.

Wow, fantastic! Best pictures I've seen so far. Many thanks, Rick and Timmy. This will really help.

Missed the question about radars and armament. the book has a pic of Pittsburgh in 1952. She still has 40mm guns, and SPS-6B radar.

Good info, thanks..

Hello to all the Baltimore-class fans.
I am looking into the possibility of building the USS Bremerton CA-130 (as of it's commissioning) based on the 1/700 USS Pittsburgh CA-72 kit by Trumpeter. Currently I do not have any confirmed data on the differences between Pittsburgh and Bremerton and how I could convert one into the other. I wish to humbly ask the members of this forum if they possess and could share any sort of information or documents on the subject.
Thank you all in advance.

Here are a couple of aerial overall images of USS PITTSBURGH (CA-72) and USS BREMERTON (CA-130) taken shortly after their completion and during shakedown. As far as I can tell without a detailed study, these two cruisers have the same armament, with the possible exception that the single 20-mm mounts were partially or completely replaced by twins on BREMERTON. The radar suite, including on fire control, is a bit different than on PITTSBURGH. Plus, RCM equipment was added. Updated Fire Control Equipment appears to be installed on BREMERTON.

I don't have any closeup views of BREMERTON.

In 1/700, many of the small detail differences would hardily show.

In East Bremerton at the top of the Warren Avenue Bridge is a small monument consisting of one each of Bremerton's anchors and a 40 mm Quad.

Has the 1/350 Baltimore announced by Trumpeter half a decade ago ever seen the light of day?

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Assessing the impact of new area rug under modeling table.

Not yet.

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De quoi s'agit-il?

Hello!
I have this drawing of the USS Baltimore from around 1944/45 and I don't know how accurate it is.
My issue are the directors for the Bofors guns. The drawing shows what looks like 26 directors while she only carried 12 quad Bofors mounts. I'm sure the red ones are Bofors Directors, the Orange ones are likely Bofors directors but the green and blue ones I do not know.
Did the Baltimores carried more then 1 director for each Bofors mount???

You are seeing a mix of the Mark 51 directors, Mark 57 directors, and sky lookout positions - only the Mark 51 and Mark 57 directors controlled the guns. All of the directors are identifiable in the October 1944 yard photos of CA-68 at Mare Island. It's interesting that BALTIMORE was only fitted with three Mark 57 directors (as I understand it most of the larger units received four of these directors for auxiliary quadrant control for the 5" and 40mm guns), but perhaps other researchers more knowledgeable than me know why.

I labeled the equipment on the drawing here:

Thanks that helps, that drawing seems to show her in her between her 1950's and WW2 state as the radar fit seems WW2 but many Oerlikons got removed.
This drawing from Friedman's book shows Oerlikons in place of those directors I could not identify previously:

The drawing from Friedman's US Cruisers shows BALTIMORE in the "as launched" configuration seen prior to her October 1944 refit at Mare Island. The original annotated drawing (from Profile Morskie) shows BALTIMORE in the October 1944 fit, with updated radar fit and changes to the anti-aircraft battery.

Yes, good callout. The Friedman drawing then depicts the ship in late 1943 after radars and the stern 40mm was installed. Profile Morskie shows the October 1944 refit.

“As lunched” configuration would have no guns or turrets of any kind. You mean “as commissioned” configuration?

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Assessing the impact of new area rug under modeling table.

Some (all?) of the cruisers were commissioned early in the war without the normal complement of guns, directors and radars. It was common to install one or two 20 mm Oerlikons in place of a 40 mm Bofors for the ship's shakedown cruise. Sometimes the gun directors were not installed. There was a shortage of some of these pieces and substitutions were common.

When the ship went into the yards to correct any deficiencies discovered during the shakedown the normal complement of guns was installed (if available). In some cases the 40 mm guns weren't installed until the ships reached a forward staging area.

For this reason you have to be careful when using shipyard photos taken before the ship was commissioned. They often do not represent the ship's actual fighting configuration.

Phil

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A collision at sea will ruin your entire day. Aristotle

Phil,

That isn't quite accurate. Many ships, depending on the builder, didn't launch with all or maybe no armament. Weight was a concern and the armament could be installed at fitting-out. Yes there were changes made "Post-Shakedown" on most all ships. On USS BALTIMORE and the class as a whole, the "Authorized Armament" was changing as the war progressed. When "completed" (post commission on 15 April 1943) and went on her Shakedown as the first of her class, many bugs (big and small) likely came to light and corrections made Post-Shakedown. Her initial "authorized armament" had six quad 40-mm mounts and it appears 24 20-mm guns. The 20-mm guns were there because they were authorized. The authorized armament for the BALTIMORE class was changed to twelve quad 40-mm mounts (48 guns) on the first units with two aircraft cranes. BALTIMORE had this change made Post-Shakedown by June 1943. The next BALTIMORE to complete had the full 48 40-mm guns installed prior to completing. The follow-on BALTIMORES with one crane, had eleven quad and two twin 40-mm mounts (keeping the same number of 48 guns). Actually, the BALTIMORE class saw fewer armament changes during the war than many other ships, retaining a 40-mm battery of 48 guns.

The CLEVELAND class went through many more "authorized" armament changes because they started to be built and completed well before the BALTIMORE class.

40-mm gun installations were not and generally COULD NOT be installed in a forward staging area. Too many structural changes were needed to be done to install these mounts from providing power to operate the mounts, interfacing to the fire control, ammo magazines and the methods to get ammo to the mounts. The only way that 40-mm mounts could be installed in a forward area, was as replacements to existing mounts. During construction there were periods when all of the 40-mm mounts were not available to be installed prior to Shakedown, due to demand for the guns. The ship's infrastructure to operate the 40-mm mounts were completed and the missing 40-mm mounts would be installed Post-Shakedown or as could be arranged. 20-mm guns on the other hand, could be installed in a forward area. The only complication, were the power and interface connections for the Mk 14 gunsights. Mostly the forward area 20-mm guns were "authorized" installations, but rules could be bent and more added than authorized, but would be corrected during the next overhaul.

There was one other consideration leading to the changes being made post-shakedown, especially for ships built in "private" (not navy owned) shipyards. Ships were built to "contract plans", and any deviation from those plans involved extra money for the alterations. When global changes were made to a design, the navy would specify that all after this or that ship would have the altered configuration done by the builder, while those before the specified change point would continue using existing plans and have the alterations done by a navy yard post-shakedown. This was especially true for alterations involving ripping out of previously completed work. This kept the cost down and limited the construction bottlenecks that slowed down production.