In the first photo in dry dock, there seems to be a large "lump" under the support right above the head of the man. Am I seeing things? This would seem very detrimental to what was a "hot rod" built for speed records. Thanks, John
Okay, my standard explanation. Other than hatches and exterior access panels, there are NO hull panel lines on submarines. Submarines are subjected to 100s of Lbs. pe square inch of pressure. At Alfa test depth of 400 meters, the pressure would be 5700 Lbs/sq inch. The welds take considerable effort and you are melting the metal together to form a strong bond that will not yield under the stress of sea pressure. Aircraft panel lines are very different; they are not subjected to the kind of stress that submarine hulls bear.
One big difference between US submarines and former USSR and Russian submarines is that when you look at a US submarine hull, you are looking at the pressure hull. With few exceptions, the Soviet/Russian hulls are double hulled, with the inner hull being the thick pressure hull. The submarines' outer panel have limber (free flood) holes to flood the space between the inner and outer hulls. There are visible on the outer Alfa hull (in my B&W closeups) faint join areas, in addition to limber holes. If I was going to model the weld lines, I would use subtle variations in paint shades to delineate them. Take a look at the Alfa photos in the 2 links. You can see how subtle the lines are (almost non-existent to the eye). The welds were very tight in the outer hull, and the hull was as smooth as possible due to the Alfa's speed. Scroll down on the second link for more dry dock photos to illustrate the point.
Alfa design goes back to the late 1950's. To their credit, this design included the titanium hull, a small crew with a great deal of automation, and a liquid metal (lead-bismuth) OK-550 reactor, which had greater power density than the pressurized water reactors. This combination of streamlining and reactor design allowed the submarine to reach great speeds of around 40 knots. But, at high speed, the Alfa was extremely noisy and could be tracked by SOSUS arrays from thousands of miles away. The liquid metal reactor was also problematic; it had to be kept "warm" (>50C) or the metal would freeze in the reactor core. The original hull, K-64, suffered such an accident where the metal solidified shortly after going into service. She was cut in half and the front half used for training. Another reactor in K-123 had a liquid metal spill of two tons into the reactor compartment. In the end, these were expensive to build, expensive to maintain, and had more than one serious reactor incident in the six hulls built.
Alfa in dry dock
Several photos-scroll down
to T. Dougherty
Thanks a million for your explanation..... it makes a ton of sense. It is great to understand just a little more about the truth regarding 1:1 scale construction of modern subs.
So then, on my 1/72 Alfa weld lines would actually be highly inappropriate if I wanted realism --- would visible welds along fictitious outer hull plate / panel lines maybe be cosmetically-speaking something to consider for the finished look of a model? It is like showing panel lines on model aircraft because to omit them makes the surface of the aircraft model smooth and I've heard such models looking "toylike" --- when in actuality 1:1 aircraft panel lines at 1/32 scale would truly be invisible, but are shown for cosmetic reasons as just mentioned?
Are these submarine weld or 'plate / panel' lines similar to outer hulls of ships like 1/72 "Snowberry" corvettes or the revell 1/72 U-Boats or Gato submarines please? I'm just trying to get a picture of reality versus modeling visual appeal and cosmetics.
Really, I thank you again my friend T. Dougherty..... you are indeed my "submarine expert" for the day