CDR_Ret

Working on the escape trunks, now that the grandfather journals have been delivered to all the cousins and siblings...
 
The Sturgeons had two escape trunks. These acted like airlocks in spacecraft to allow emergency egress in case the boat was bottomed for some reason. The only difference is that there is high-pressure sea water outside instead of a vacuum.
 
Basically all US submarines following WW II had the capability to mate with the McCann rescue chamber. This required a flat surface surrounding the upper escape hatch fairing, which was equipped with a haul-down bale, external hatch operating gear, and, later, anchor points for the Deep Submergence Rescue Vehicle (DSRV) snubbers. The flat landing surface on the albacore/cylindrical hulls had to be faired into the hull shape.
 
So, I tried to illustrate all of these features in this model. The haul-down bale was actually attached to the emergency buoy cable, which was manually released from inside the ship. The buoy carried a cable to the surface of the ocean, to which the rescue device was attached by divers. The DSRVs used the cable to visually guide the vehicle to the stricken sub. The DSRV would mate to the hull above the hatch, then attach snubbers to the four rings to steady the vessel before blowing the skirt dry and entering the sub. In truth, this is a lot of surmising, since none of my boats ever went through a DSRV drill or deployment exercise.
 

Location of the fore and aft escape trunks. The forward trunk was in the bow compartment and the aft trunk was in the engineroom.
 

This is the forward escape trunk landing area. I had difficulty modeling these because I don't recall them being so prominent. But there were other things surrounding them like safety tracks, so perhaps they were.
 

The aft escape trunk.
 
Since the upper parts of the escape trunks and hatches were located within free-flooding areas and/or ballast tanks, there were a lot of other pieces of gear associated with them that couldn't be installed in way of the pressure hull. These included line lockers, the emergency buoy, retractable cleats, towing fairleads, hydraulic capstans, and so on. Given time, I may actually get to those.
 
Terry

A sea lawyer maybe????   LOL.

Keith, are you a lawyer by any chance?

I have to add my two cents here!
 
My first "ship" was a 112 foot long inshore mine sweeper (MSI). Three officers and 19 enlisted. I was Engineering Officer, Supply Officer, George and 25 other official duties.
 
I was told, when first going aboard, that ships in the US Navy were 150 feet or longer, and anything smaller was a boat. However, we had a letter from the Secretary of the Navy authorizing us to call the vessel USS Cape, United States Ship. So the Cape and her sister the Cove (MSI 1) were the smallest ships in the Navy.
 
The Cove was probably a bit shorter than the Cape. The ships had four GMC 6-71 diesel engines ganged together to drive one 4 foot diameter bronze propeller and a 6" diameter prop shaft. The prop and shaft weighed more than the engines. If we tried to shift into reverse while the shaft was turning the momentum of the prop and shaft plus the force of the prop "windmilling" would just crank the engines over backwards, and they were happy to run that way!
 
To reverse the prop we had to pull on a brake lever that tightened a brake shoe against the shaft and hold on until the shaft stopped turning. Then we could shift the transmission into reverse, rev up the engines, let out the clutch and start the shaft/propeller turning again. Ditto when going from reverse to forward again.
 
All this messing around took several minutes and made close maneuvering tricky. Why am I telling this? One time when coming in to the pier the Cove timed the approach wrong and while trying to reverse engines to slow down it rammed the stern of a destroyer in the berth ahead. It cut a several inch deep "V" shaped notch in the destroyer's stern. The destroyer presented the Cove with a new name plate for the "USS Can Opener."
 
So the Cove was probably the shorter of the two. And there were only two. They were worthless.
 
PS: One of these days I may build a model of the Cape. A wooden model of a wooden ship.

Just don't call a ship a boat, unless it's a submarine!
 
I don't know how many articles I read over the past several weeks about the "boat" stuck in the Suez Canal! 🤨

Keith, are you a lawyer by any chance?

Well, when a ship behaves well in a seaway, sailors say she's a "good seaboat". 
 
I submit the two things are largely synonymous, with the distinction being  merely a matter of convention. Of course, an aeroplane or even a spacecraft can be a "ship", and a "liner", but never a "boat", unless the aeroplane in question has a hull: then it's a flying boat, but only if it has one hull, never two. And a helicopter can never be a "flying boat", even if it has a boat hull, like a Sikorski Sea-King. But it can still be a "ship" or even a "liner" if it flies scheduled routes. Gunboats are "boats", even the biggest kind, with commissioned officers on a bridge, and a wardroom and accommodations and a galley and the whole nine yards.  Again, an aeroplane or helicopter can be a "gun ship" but never a "gun boat"; it's only the boat one that can be called a "boat"... but only if it's not a FLYING boat. Then it's a "Gun ship". 
 
I suppose if you took the guns off a large gun boat, it would be a small ship. I mean, what else would you call it? 
 
Of course, you can call a small steam-powered ship a "steamboat", but if you change the steam engine for a diesel, then it's a "ship", not usually a "diesel boat", unless it's a submarine or a tug. Or one of those colossal ships that sail in the Great Lakes: those are obviously "boats" whether they're steam or diesel or whatever. As for seagoing ones, you can have "steam ships" but if they're diesel powered they are suddenly called a "motor vessel" even though they all have engines, not motors. Which brings me to the subject of the difference between engines and motors....
 

Just don't call a ship a boat, unless it's a submarine!
 
I don't know how many articles I read over the past several weeks about the "boat" stuck in the Suez Canal! 🤨

Just don't call a ship a boat, unless it's a submarine!
 
I don't know how many articles I read over the past several weeks about the "boat" stuck in the Suez Canal! 🤨

So modern frigates are boats!
 

There are no "ships" on the Great Lakes.  1,000 ft ore carriers are still boats.
And of course all the submarines that were mfg in Manitowoc, WI were boats.

Just don't call a ship a boat, unless it's a submarine!
 
I don't know how many articles I read over the past several weeks about the "boat" stuck in the Suez Canal! 🤨

Yeah, I've heard these stories even back when I was still in the Navy. The circumstances change every time I hear it. The one that was popular back then was that President Clinton had authorized the sale of a poly-axis propeller milling machine to the Chinese even though it was on the strategic items restricted list (or whatever it was called).

Continuing to work from aft to forward, today is the towed sonar array tube and faring.
 
The Sturgeons were already being constructed when the US submarine force received their towed arrays. These sonars were towed a long distance behind the ships to remove the receivers from the vicinity of the largest sound source in the area—the towing submarine itself. So the early towed array systems were add-ons for the Permit-, Sturgeon-, and the Los Angeles-classes. (The towed array systems for the Sea Wolfs and Virginias are totally internal.)
 
The handling gear for the array cable was installed in a forward ballast tank and the sonar array itself was stowed in a long tube that led to the stern planes. The "flushing tube" laid against the hull and was covered by a low fairing topside. The aft end of the tube had to extend far enough aft so that when the ship executed a sharp turn, the array wouldn't be cut off by the prop. (The Soviets solved this problem by putting their array and handling gear in a pod on top of the vertical stabilizer of the rudder.)
 
The sonar tube was called the "flushing tube" because the array was deployed and retracted by pumping water through it to "flush" the array out and lubricate its retraction.
 
The most difficult part of modeling this component was the topside flushing tube fairing, which twists in three dimensions as it lies along the hull.
 

Sturgeon Class Towed Array Flushing Tube and Support
 
 

Aft view of the Towed Array Flushing Tube
 

Towed Array Fairing
 
Modeled in DELFTship
 
Terry

Continuing to work from aft to forward, today is the towed sonar array tube and faring.
 
The Sturgeons were already being constructed when the US submarine force received their towed arrays. These sonars were towed a long distance behind the ships to remove the receivers from the vicinity of the largest sound source in the area—the towing submarine itself. So the early towed array systems were add-ons for the Permit-, Sturgeon-, and the Los Angeles-classes. (The towed array systems for the Sea Wolfs and Virginias are totally internal.)
 
The handling gear for the array cable was installed in a forward ballast tank and the sonar array itself was stowed in a long tube that led to the stern planes. The "flushing tube" laid against the hull and was covered by a low fairing topside. The aft end of the tube had to extend far enough aft so that when the ship executed a sharp turn, the array wouldn't be cut off by the prop. (The Soviets solved this problem by putting their array and handling gear in a pod on top of the vertical stabilizer of the rudder.)
 
The sonar tube was called the "flushing tube" because the array was deployed and retracted by pumping water through it to "flush" the array out and lubricate its retraction.
 
The most difficult part of modeling this component was the topside flushing tube fairing, which twists in three dimensions as it lies along the hull.
 

Sturgeon Class Towed Array Flushing Tube and Support
 
 

Aft view of the Towed Array Flushing Tube
 

Towed Array Fairing
 
Modeled in DELFTship
 
Terry

Took a few hours this weekend to build the submarine rudders and the stern light.
 

 
The Sturgeon balanced rudders acted together on a single shaft. The lower rudder worked as a standard rudder when the ship was surfaced. Submerged, the upper rudder added twice the turning leverage. Let's just say that these SSNs were pretty nimble when submerged. At a flank bell, you had to hang on during the turn!
 
Sturgeons had a single, combination stern light housing. The lower enclosure provided the screening needed for the 135-degree stern light used underway. The upper lamp was the 360-degree aft anchor light. Both lamps were in pressure-proof globes rated to the ship's maximum operating depth. The light to be illuminated was selectable from inside the ship.
 

 
Terry
 
 

Yesterday night I found your post about your method of drawing and laser cutting frames by mere chance. I was fascinated, because I have some experience in drawing with Adobe Illustrator, but not with working in 3D.
Until now, I used Illustrator for tracing the lines of frames in plans that I bought, just to make bulkheads and keels. Now I traced all the frames of "La Belle 1684" in plans of Jean Boudriot (published by Ancre) - this time, instead of laser cutting, I had the opportunity to cut them out using a CNC milling machine for a small hull model in 1/64 (as you know, you can easily export a drawing from Illustrator in dxf format, but this file has then to be worked on before feeding it to the machine).
Tracing by hand has its limits (even with the clever support using bezier curves), the problems begin with the plan itself (distortions, errors), followed of course by limits of my own. Creating a correct hull in 3D helps making sure that all the parts fit in. It seems that Shade3D and Illustrator are capable of working hand in hand.
As always - the better the source, the better the outcome. By tweaking and sanding, my frames seem tho fit, but not with the precision one could wish for. That's why I will read your manual with utmost care (and try it out with my newly arrived copy of Ancre's "La Volage").
A admire your generosity, and thank you with all my heart.
Yours,
Gregor

One of my dad's former students was stationed aboard USS Aspro (SSN-648), a Sturgeon-class boat.

Took a few hours this weekend to build the submarine rudders and the stern light.
 

 
The Sturgeon balanced rudders acted together on a single shaft. The lower rudder worked as a standard rudder when the ship was surfaced. Submerged, the upper rudder added twice the turning leverage. Let's just say that these SSNs were pretty nimble when submerged. At a flank bell, you had to hang on during the turn!
 
Sturgeons had a single, combination stern light housing. The lower enclosure provided the screening needed for the 135-degree stern light used underway. The upper lamp was the 360-degree aft anchor light. Both lamps were in pressure-proof globes rated to the ship's maximum operating depth. The light to be illuminated was selectable from inside the ship.
 

 
Terry
 
 

Took a few hours this weekend to build the submarine rudders and the stern light.
 

 
The Sturgeon balanced rudders acted together on a single shaft. The lower rudder worked as a standard rudder when the ship was surfaced. Submerged, the upper rudder added twice the turning leverage. Let's just say that these SSNs were pretty nimble when submerged. At a flank bell, you had to hang on during the turn!
 
Sturgeons had a single, combination stern light housing. The lower enclosure provided the screening needed for the 135-degree stern light used underway. The upper lamp was the 360-degree aft anchor light. Both lamps were in pressure-proof globes rated to the ship's maximum operating depth. The light to be illuminated was selectable from inside the ship.
 

 
Terry
 
 

Everyone,
Now, the procedure manual is ready to download.
I have updated (as my understanding) and uploaded it to my cloud storage.
When you want to get this manual, please send PM to me so that I can reach you and give download key to you. It is free download now.
Many PDF and JPG files in the manual help you to look through the contents even if you do not have the specific software.
 
Kiyoo Iizawa
 

Yeah, I've heard these stories even back when I was still in the Navy. The circumstances change every time I hear it. The one that was popular back then was that President Clinton had authorized the sale of a poly-axis propeller milling machine to the Chinese even though it was on the strategic items restricted list (or whatever it was called).

Probably the most difficult aspect of a Cold-War-era submarine model is getting the propeller right. Nearly all nations with advanced submarines came to recognize the acoustic advantages of a seven-bladed, minimum cavitation propeller. The blade shapes are extremely complex, requiring the use of a sophisticated, multi-axis, computerized milling machine.
 
I have attempted to approximate a submarine propeller in a variety of 3D CAD programs including Sketchup, Blender, and now DELFTship. None of them are easy to use. There is nothing symmetrical about a propeller, except in rotational symmetry. Even then, one has to get the proper blade shape before you can duplicate and rotate the blades to their proper positions. The blades are 51.429 degrees apart (360° ÷ 7). If you are inclined to create a 3D printable model, then you have to cleanly combine the blades with the hub to make the model manifold. That was the hard part.
 
The following images provide a fairly good approximation of a US nuclear submarine propeller before the advent of the ducted pump-jet types found in the Seawolf- and Virginia-class submarines. This model was created in the latest version of DELFTship. In the process, I discovered several program bugs/properties that made the work even more difficult than it should have been ...
 

Orthogonal stern view
 

Aft stbd quarter view
 

Aft port quarter view
 
Terry
 
 

A Guide to the New DELFTship Background Images Feature
 
Attached are the five parts of a guide I have drafted up to assist modelers who think they want to get their feet wet using DELFTship. It is intended for the complete DELFTship novice, but even those familiar with the program will find this guide useful, I think.
 
Please read Part 1, which includes an intellectual property disclaimer.
 
If you have any comments or corrections, please feel free to post them here so everyone can be aware of them (and I can fix them). I am particularly interested in fixing things that are unclear or don't work as intended.
 
Be sure to install the latest version of DELFTship (13.10 (328 or later)) before you use this guide. It's almost completely incompatible with earlier versions!
 
Thanks.
 
Terry
Part 1-DELFTship_Bkgrd_Images.pdf Part 2-DELFTship_Bkgrd_Images.pdf Part 3-DELFTship_Bkgrd_Images.pdf Part 4-DELFTship_Bkgrd_Images.pdf Part 5-DELFTship_Bkgrd_Images.pdf

Just for fun, I thought I'd try out whipping out a Sturgeon-class SSN hull using the new background image feature in DELFTship. Setup was really quick. Shaping the hull was another story...
 

Plan: USS Sturgeon (SSN 637) by Greg Sharpe 
 
Being an old submariner, I may spend a little time on this!
 
Terry