The Ship Model Forum

CC Clarke wrote:The Prairie Masker system's purpose was two-fold, taking advantage of sound transmission trying to pass through two very different mediums (air being 1/4 the density of water: Approx 1100 fps compared to 4800 fps.) The Masker attenuated own-ship's noise and degraded active sonar returns.

Prairie refers to the air released to reduce cavitation. Masker was the "bubble curtain" which enveloped the hull.

The sail is a huge flat surface whose sides reflects active sonar. Sound doesn't transmit through water to air to water efficiently as it tries to pass through bubbles. Some surface ship classes have employed versions of the system.

Anechoic tiles were the next evolution in external sound silencing and active sonar attenuation, in addition to acoustic countermeasures, which are launched when you've been snapped-up (detected); -another topic altogether.

Tom Dougherty wrote:My resin 1/350 version of a Guppy submarine is in the � What�s New� section. Unfortunately, the ModelWarships main page has not been updated to reflect the posting of my model as well as two additional models.

Tom

Vepr157 wrote:

Woodstock74 wrote:Interesting, so the only possible visual indication of Prairie/Masker are what are effectively pipes I'm guessing running outside the pressure hull/exterior cladding?

Right. The hull emitters are often difficult to spot, but the stern ones are very apparent. Although it's not a fleet boat, this photo shows the aft piping on the Tang (the pipes look pretty much the same on GUPPYs):

Woodstock74 wrote:Interesting, so the only possible visual indication of Prairie/Masker are what are effectively pipes I'm guessing running outside the pressure hull/exterior cladding?

Woodstock74 wrote:Is this shot of the Tork's screw indicative of Fleet Snorkel screws? As this image is of her in dry dock in modern day, wanted to make sure what I'm seeing would be accurate to in-era. I'm specifically wondering about the slots in the screw boss trailing edge. Is this part of the Prairie system?

Tom Dougherty wrote:Here�s hoping she stays just down the road. The plan by Patriot�s Point was to sink her for an artificial reef for divers. The exterior hull is in bad shape, but the interior is in excellent condition. It is the sole remaining Guppy III.

Yeah, the printed description of the 1963 edition is sparse, to say the least. If it is not a reprint, but an update, I would expect it covers Guppy III.

I do know that the Guppy III program was an early 1960�s effort. The motivation to modify existing Guppy subs to Guppy III standard was due to the slow build up of nuclear SSNs. This was partly due to the diversion of building to the Polaris SSBN program, and later the delays due to the loss of Thresher and implementation of SubSafe measures.

Tom Dougherty wrote:There are two versions of the Guppy submarine book. The 1956 edition book is an update of the WWII Fleet Submarine Manual, hence a highly technical, nuts & bolts coverage of submarine systems. It uses Becuna, SS319 as the example. Becuna was a Guppy Ia, so features such as the expanded 514 cell battery of Guppy II are probably only mentioned. Since it was published in the 1950�s, coverage of the heavily modified Guppy III e.g., Clamagore) are absent. There is a later, 1963 Edition Submarine book also listed on the site below. That appears to cover the later and final evolution, the Guppy III. Again a highly technical coverage of the systems in these boats, The Guppy III boats were literally cut forward of the control room and a 15 foot �hull plug� installed to create space for an expanded sonar suite. Externally, they all had the High Atlantic Sail and three PUFFS sonar fins on deck. You can see more in my coverage of Clamagore here: http://navsource.org/archives/08/pdf/0834331.pdf

Best source for the books (least expensive) is probably Periscope Films. Here are the manuals, including both of the Guppy manuals.
https://periscopefilm.com/submarine-manual/

Tom Dougherty wrote:So that book is an update of the WWII Fleet Submarine Manual, hence a highly technical, nuts & bolts coverage of submarine systems. It uses Becuna, SS319 as the example. Becuna was a Guppy Ia, so features such as the expanded 514 cell battery of Guppy II are probably only mentioned. Since it was published in the 1950�s, coverage of the heavily modified Guppy III e.g., Clamagore) are absent. There is a 1963 Submarine book also listed on the site below. Whether that covers Guppy III, I don�t know.

Best source (least expensive) is probably Periscope Films. Here are the manuals, including the Guppy manual.
https://periscopefilm.com/submarine-manual/