Iowa and Alaska Class Conversion Projects

CV12Hornet said:
You're kidding, right?

Reboilering a battleship is Major Ship Surgery - there's a reason most navies didn't bother unless they literally couldn't buy more battleships, it costs a very significant percentage of just buying a new ship since you need to cut open the armored deck to replace them. They don't call the battleship modernizations involving new boilers "reconstructions" because it was an easy task.

For another example, recall how much work had to be done on Victorious to reboiler her. Same deal.
Click to expand...
No, I'm not kidding.

IF THE BOILERS NEED TO BE REPLACED, you drop in 1200psi boilers more like what all the newer ships use. You're cutting the ship up regardless of which type of boilers you install, so you install the most up-to-date.
 
Scott Kenny said:
No, I'm not kidding.

IF THE BOILERS NEED TO BE REPLACED, you drop in 1200psi boilers more like what all the newer ships use. You're cutting the ship up regardless of which type of boilers you install, so you install the most up-to-date.
Click to expand...
That's not the point. The point is, if the boilers are that bad, the ship is no longer a reactivation asset since it would cost 85-90% of the cost of just building a brand new battleship. The Navy only did it in the inter-war years since they were not allowed to build new battleships by Treaty. Remove the Treaty, and they never would have even considered doing that. Same here. If the Iowa class boilers had been worked that hard (or maintained that poorly), they never would have been considered for reactivation and modernization.
 
SSgtC said:
That's not the point. The point is, if the boilers are that bad, the ship is no longer a reactivation asset since it would cost 85-90% of the cost of just building a brand new battleship. The Navy only did it in the inter-war years since they were not allowed to build new battleships by Treaty. Remove the Treaty, and they never would have even considered doing that. Same here. If the Iowa class boilers had been worked that hard (or maintained that poorly), they never would have been considered for reactivation and modernization.
Click to expand...
Ah, gotcha!
 
SSgtC said:
And no Navy ships have ever used a steam plant even approaching 3-4,000 psi.
Click to expand...
For reference, that would be a supercritical steam plant. The first land-based supercritical plant didn't exist until 1957.

So far as reboilering goes: about the only non-replaceable elements are the steam and water drums. Those are life-of-ship components: the design expectation would be that by the time the boiler drums are worn out, the rest of the ship is equally knackered and the only economic option is the breaker's yard. Same thing with steam turbines and gearboxes.
 
Okay, out on a limb time, but I recall reading there were spots designed into their hulls to access the boilers and engines from beneath the ship, so no need to cut through the armor. I may be mis-remembering something however, so take this with a pillar of salt.
 
That would make sense. Nuclear-powered ships have access shafts for the reactors, and gas turbines can usually be pulled out via the funnels.
 
They look like SK-1 but by the the end of WW2 SK-2 was the standard so they are some early SPS-?
 
Last edited:
Yes the Gunars of the 3"/70 guns mountings on-board radar but apparently they were removed from the in-service mountings.
WNUS_3-70_mk37_sketch_pic.jpg
 
Scheme F: 2 x 8"/55 quads, 20 x 5"/54 twin, 3 x 3"/70 twin
2 x Mk.54 for 8"
4 x Mk.37 for 5"
4 x Mk.56 for 5"
3 x Gunars for 3" twins

Scheme G: 3 x 8"/55 quads, 16 x 5"/54 twins, 6 x 3"/70 twins
4 x Mk.37 for 8" and 5"
4 x Mk.56 for 8" and 5"
6 x Gunars for 3"/70

Scheme H: 4 x 8"/55 quads, 14 x 5"/54 twins, 6 x 3"/70
4 x Mk.37 for 8" and 5"
4 x Mk.56 for 8" and 5"
6 x Gunars for 3"/70

Note that the Gunar system had the radar antenna on the gun mount, hence there is one Gunar per 3"/70 turret, this would have been Gunar Mk.2. Its also noteworthy that Scheme F uses the Mk.54 fire control system for the 8" guns as in the Des Moines class whereas the Schemes G and H rely on the Mk.37 resulting in a lot of barrels per director.
 
Aha, I was right: GUNAR was a Mark 64 gun director (the derivative of Mark 63 one) placed on gun mount itself. The previous Mark 63 used separate director, but the AN/SPG-34 tracking radar was installed on gun mount itself. The arrangement was a bit... illogical (separate optical director, with radar on gun mount), so Mark 64 was an attempt to gather all components - gun mount, radar and director - together in one system. BuOrd named such systems "GUNAR", apparently "GUn And Radar", but the result proven to be overcomplicated, maintenance-heavy, and by late 1950s wasn't used anymore.
 
Tzoli said:
Yes the Gunars of the 3"/70 guns mountings on-board radar but apparently they were removed from the in-service mountings.
Click to expand...
If I understood it correctly, GUNAR was a generic term for such on-mount radar systems, jntroduced by BuOrd in early 1950s, but it didn't stuck. The 1950s electronics and gun recoil mixed rather poorly, and the mounting became overcomplicated and utter headache to maintain. So the idea was dropped, and then the term GUNAR also.
 

Similar threads

Back
Top Bottom