Calling all Los Angeles SSN-688 class fans

[Tom Dougherty]

Also included are these little extra pair of fins or something just before you get to the stern of the boat. You can see them in the Hobby Boss box art. They come out on the lower hull at about 45 degrees or so.

OK, Tracy answered their purpose (reduce snap roll and hold countermeasures) but do NOT mount them at a 45 degree angle! If you were looking at the hull for the rear, they are more like 65 or 70 degrees (more horizontal less vertical) than 45 degrees.

Here's some shots of USS Greenville in drydock. If you look carefully (they are not at the best angle for photography), you can see the anhedrals in all three photos:

In this shot, the anhedral is just visible below the sternplane, about where the red & black hull demarcations meet:
http://www.cpf.navy.mil/subsite/ehimema ... 26-med.jpg

This shot taken inside the drydock also has the anhedral visible at the rear, just below the sternplane. It is clear that the mounting is more horizontal than at a 45 degree angle:
http://www.cpf.navy.mil/subsite/ehimema ... 27-med.jpg

In this final drydock shot, a portion of the anhedral is just visible below the sternplane:
http://www.cpf.navy.mil/subsite/ehimema ... 25-med.jpg

[redoctober27]

is USS Greenville's hull paint scheme standet for a los angeles class sub? Or dose the hull colors and that changes from year to year?

[Heavy Melder]

Howdy gents. Last night a friend had the Riich Models 1/350 LA class, and I had the HObbyboss 1/350 and we compared. Is it just me or does the Riich Model bow shape seem too pointy? Or is the Hobbyboss bow too blunt? Anybody know for sure? Detail level seems the same to me.....

[Tom Dougherty]

Here's a handy Bow Cap Template for several classes, including the 688s. That should allow you to compare the two models.

[Tracy White]

OK, let's post some figures and see what everyone comes up with. Tom; a question; the "Bow cap template" means that this is the dimensions of the non-metallic nose cone, yes? I wanted to clarify that in case the following assumptions are wrong.

I took a screen shot of the graphic and resized it a bit until it was close (slightly larger) to the same size as the Riich kit, which I have (don't have the Hobby Boss yet). Eyeballing it shows it's pretty close... perhaps a touch narrow forward, but perhaps only by a scale foot or two on each side for about 10-15 scale feet. End of the cone on the drawing matches the kit. However, that's all visual inspection, with perspective error and no guarantee that I actually scaled it correctly.

Converting the imperial measurements to metric, I get 7498.08mm for the length and 8107.68mm for the width, which scales down to 21.42308571 and 23.1648 mm respectively. Annoyingly, my calipers have disappeared. At the aft edge, the engraved line for the cone APPEARS to be about 23.5mm wide versus the 23.16 it should be... I think I can forgive this. However, the engraved line appears to be about 1.5mm further aft than it should measure. Can't quite rectify how the extreme aft beam appears correct but the length doesn't... probably just improper visual line-up on my part.

I'd call it close at this point. I'll keep an eye out for my calipers or buy another set this weekend.

[Heavy Melder]

hrmmm. using the image I compared the hull shape would seem to be off, however in the drawing the sides of the cone seem rather flat towards the point where they join the hull wouldn't you say? And when looking at the bow in photos, it doesn't look that way. It's more of a gentle curve like the 637 class in the image. And that's what the Hobbyboss kit seems to be matching.

And before we get too crazy, "non-metallic nose cone" should be clarified, as I'm a noob and don't understand everything yet.

[Tracy White]

And before we get too crazy, "non-metallic nose cone" should be clarified, as I'm a noob and don't understand everything yet.

The bow contains the sonar array, so the cone itself needs to be "transparent" to the active signals and not impede any passive abilities. Thus, it's a non-metal structure. I don't know the exact composition, but it's a construction similar in many ways to fiberglass.

You can see a bit of SSN-711 San Francisco's dome here following a collision.

[Tracy White]

Here's the picture I shot last night... the red is a flood fill between the Ohio and the 688 class profiles to make it easier to see the 688 profile:

Note that this is slightly over-scale just to compare.

[Heavy Melder]

Here's the picture I shot last night... the red is a flood fill between the Ohio and the 688 class profiles to make it easier to see the 688 profile:

IMG_30281.jpg

Note that this is slightly over-scale just to compare.

hrmm looks like I should invest in the Riich Model kits......if it lines up that well, I should get one and compare the two. Thanks for the comparison.

[Tracy White]

I picked up the HobbyBoss kit last night but haven't had a chance to do the same comparison yet... hope to tonight.

[Heavy Melder]

Two questions:

Tracey, have you had a chance to compare the Hobbyboss and Riich models bow profiles yet? and

Anyone working on extra bits for these kits like the Advanced Seal Delivery System (ASDS)? Or anything else like that?

[Tracy White]

Cursory examination... not good enough to really report on. I had already glued my two lower hull halves together on the Riich kit, so I can't directly compare the lines. To be honest I forgot about doing more the last couple of days, what with the other stuff on the work bench. I'll try and get back to the comparison tomorrow... good news is that I did find my calipers!

With regards to aftermarket.. I suspect that with Dragon's kit out there for so long, if someone was going to do DDS or anything it would have happened. ASDS system is dead, so I doubt we'll see anything in that vein:
http://en.wikipedia.org/wiki/Advanced_S ... ery_System
But there's always hope!

[FRAMSailor]

Lots of great information here, since most of my knowledge is limited to tin cans. However, I have a question about the other end of the 688. Does the screw on the Riich kit accurately represent the real thing? It seems to be very large and swept back? Sorry if this has already been covered, but if it was I missed it.

[Tom Dougherty]

Note: This is the third f%#*ing time I've tried to post this answer, and the server keeps going down.

Yes, if the kit propeller looks anything like the below photo of an early Los Angeles propeller. There was significant skew back to these propellers, and the shape was to mitigate the low frequency "Blade Rate" acoustics problem, which carried very far in the deep sound channel.

The later (688I) propellers had a ring atatched at the tip, for protection during under ice operations (second photo). You can also see the anhedral angle well; note it is more horizontal and not at a 45 degree angle, as is often depicted

[Tracy White]

It looks like the ring also allowed them to completely re-profile the blades as well; more paddle and less scimitar.

Hobby Boss blades on the Left, Riich on the right.

HobbyBoss to the left and Riich to the right. I don't think either looks right; in fact, the old Dragon prop looks better to me.

Here's the HobbyBoss bow for comparison to my earlier Riich look:

HobbyBoss Bow

I had a harder time making this one "fit." It looks like it's a little too flat at the nose and doesn't flare out enough aft. Really, both look good to me. It's a tube with a rounded bow... not that difficult, and the lines look right to my eye, which admittedly has not spent years looking at the things in drydock... so I'm uncalibrated.

However, using Tom's drawing and my conversions, we can take a wee bit of a look at shapes and other details. The sonar dome aft diameter is 26'6" and "Cold War Submarines: The Design and Construction of U.S. and Soviet Submarines" By Norman Polmar lists the hull diameter as 33'.

That translates to just over 23mm (23.1648mm to be precise) wide at the aft end of the sonar dome and 28.73mm in 1/350th scale.

I get 28.58mm beam and 23.64mm at the end of the sonar dome on the Hobby Boss kit. Seems close enough, but the sonar dome should be about 21.5mm long, and I measured mine at 19.86, which is ~22.6 inches, or just under two feet two short.

Anyone feel like re-scribing a ring on a compound curve for less than two scale feet?

On to the Riich model. 28.74mm on the beam and 23.45 at the end of the sonar dome, which was 22.30mm long, or just under a scale foot too short.

Either way, we can't use the kit sonar domes to really accurately measure shape, and we're only off by a scale foot or two here and there anyway. So now let's compare the bow details a bit:

Riich above waterline to the left, HobbyBoss bow to the right.

I lined up the nose cone break as a convenient reference point. Note the HobbyBoss kit has the retractable bits spaced further apart. I don't have the time to go through the Navy Image gallery to decide who is more correct in this.

[Tom Dougherty]

Thanks for doing all that measuring, Tracy!

BTW, the skew on the kit blades both look less extreme than they should for an early 688. Look at the small photo above. I'm also not sure if the skew angle changed; that may be a kit thing and not reality. Those blades were made based on actual acoustic data, very sophisticated computer models, and very large CAM equipment. I notice there is something missing on the propellers as well, but that's another story...

I am travelling and don't have my LA class plans on hand. But it looks like the one on the right (Hobby Boss) got the shape of the VLS doors (which are oblong and not square) closer to the real thing. I'm not sure about the rest of the topside access hatches. One issue I have seen is that with the VLS system installed, some vents, etc. had to be moved topside. Some vendors got them right; others didn't. It can be confusing.

The old Dragon (DML) 1/350 kit of the USS Hampton had the VLS doors roughly as they were installed on the first VLS equipped ship USS Providence (SSN-719). That had four rows (lined up with the main axis) of three tubes in each. Now it is starboard- 2 outboard, 4 inboard; Port-4 inboard and 2 outboard (as in the 2 current kits) The design was changed early on and the doors reconfigured. Dragon missed that.

[Tracy White]

For what it's worth, neither kit's sail matches the pattern demonstrated here.

[redoctober27]

Hello, what would be a classic paint job for a early 688 LA class during rthe hight of the cold war I seen your pics of Uss Greenville with red hull and black nose from the early 2000s and todays all black paint job. I'm wondering if hobby bosses paint job layout would be accurate for a 688 class during the cold war. Side note I'm building the Uss dallas ( I know every one builds her but she is my faverite from the class oh and the Uss Toledo for my home city!

[Tracy White]

I don't have any drydock photos of her, but a photo on her Navsource page hints at hull red below the waterline.

[redoctober27]

Darn it! Link isn't showing up