Two steps forward. One step back!
Well, even the greats -- like me -- make mistakes.
Such is the case with the stern vertical stabilizers I, as it turned out, erroneously mounted at the tips of the horizontal stabilizers on my 1/96 scale model of the DANIEL WEBSTER, a unit of the LAFAYETTE class of SSBN’s produced in the early 60’s.
Below is a dry-dock photo of a LAFAYETTE class SSBN, clearly showing the absence of vertical stabilizers and the distinctive split upper rudder, classifying features of the class.
Note that the outboard stern plane operating shaft bearing is near the outboard tip of the planes. As the stern planes on most modern American submarines are of the ‘balanced’ type – a significant fraction of the plane surface is in front of the center-of-rotation – the inboard and outboard operating shaft bearings are situated well aft of the control surfaces leading edge. To achieve that, some boats, the LAFAYETT’s specifically, employ an outboard bearing support arm, or post, fixed to the horizontal stabilizer, that extends aft into the stern plane and engages its operating shaft. That arrangement well illustrated here.
The location of the stern plane outboard operating shaft bearing is the big difference between the LAFAYETTE and BENJAMIN FRANKLIN class boats – the much wider, tip located operating shaft bearing structure on the BENJAMIN FRANKLIN class boats providing the foundation upon which the vertical stabilizers are affixed. I’m not sure if the vertical surfaces were employed as housing for sonar elements (early PUFFS?) or not, but they did greatly improve the dynamic stability of the submarine about the yaw axis – meaning less work for the helmsman!
The Scale Shipyard 1/96 kit I’ve had all these decades therefore represents the BENJAMIN FRANKLIN, not the LAFAYETTE class SSBN, as I had mistakenly assumed. The three major physical differences between the two classes is the location of the planes on the sail (a moot point on my DANIEL WEBSTER model, as it had those planes mounted over the bow); the use of a fixed vertical stabilizer under the upper rudder, and the absence of vertical stabilizers on the LAFAYETTE class boats.
It was all there in my documentation: my qualification notes, dry-dock planes, booklet of general planes, and several photos of the DANIEL WEBSTER and other LAFAYETTE class SSBN’s in dry dock. If I only paid attention to that I would not have found myself chasing my tail as I fell down the rabbit-hole of, ‘gee! … looks neat, let’s stick those on the ass-end of my toy submarine!”
As a closer look at my documentation revealed, those vertical surfaces were a feature of the later BENJERMAN FRANKLIN class of SSBN, not the LAFAYETTE class of which my DANIEL WEBSTER was a member.
I erroneously assumed (NEVER assume!) that some boats, including my boat, got these as a yard-period retrofit. I have found nothing to substantiate this assumption. So, the damned things I worked so hard to install had to come off!
So -- to better illustrate the difference in how the outboard stern plane operating shaft bearings were situated between the two nearly identical classes of SSBN’s -- I halted the work after most of the change was done on the port side, but not yet done to the starboard. This illustrates the difference between the two configurations.
Note the two snipped off vertical stabilizers in foreground (sob, sob … sniff, sniff).
As the vertical stabilizers featured a G-10 fiberglass core that ran through the bearing foundation I found the best tool for removing them was a thin-blade, un-reinforced carbide cut-off wheel. The rough work done, the roots of the vertical stabilizers were ground down with carbide burr, flat files and a sanding block.
It’s so much easier to destroy than to create.
When kerf is our friend: The width of the stern plane operating shaft outboard bearing posts at this scale came in at a bit over 3/32”. To achieve these slots in the horizontal stabilizer and stern plane I found that taping two hacksaw blades together and using this tool to saw the slits was the best solution to the problem. The bearing post itself is a piece of Sintra plastic sheet cut to shape and drilled at its end to pass the stern plane operating shaft.
The vertical stabilizer foundation was cut back to the trailing edge of the horizontal stabilizer and the concave trough that nested the leading edge of the stern planes was roughed out with round files. The void at the tip of the stern plane was built up from RenShape and worked to shape.
The gross filling and contouring was done with Bondo, followed by air-dry touch-up putty, and lots of sanding. Only then did the fist coat of gray primer go down to check the work. You see how the stern plane operating shaft slips through the two bearing points – one bearing point at the hull, the other at the outboard bearing support arm. A set-screw in the stern plane makes it fast to its operating shaft, the torsion force to move the stern plane is through an internal yoke that makes up to both operating shafts and affords clearance of the centrally running propeller drive shaft.
All modern American combat submarines up to the LOS ANGELES class featured one or more escape marker-buoy systems. In the event the submarine is grounded at a survivable depth (in reality that means pier side, or just well within the continental shelf) the marker buoy is released and rises to the surface, as it does so an attached ‘down-haul’ cable is paid out, the cable running through a ‘bail’ or fairlead situated over the escape trunk hatch, dead center of the surrounding seating ring that would be used to make the water tight seal between McCain rescue bell or DSRV skirt and the stricken submarines escape trunk.
The down-haul cable is wound on a drum set in the superstructure near the escape trunk upper hatch. On the model I represent the short length of down-haul cable running from the drum, up through a fairlead hole in the deck, straight to the escape hatch down-haul cable bail. Another wire, coming out the top of the bail runs to the escape buoy marker.
While I was at it I inserted the four hold-down padeyes that circled the escape hatch and sat within the seating circle – these artifacts from the old McCain rescue chamber system. All the required holes drilled, wire fitted and checked, it was all taken apart and set aside until all painting and weathering had been completed on the model.
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