Question about Skipjack Ballast Tank Vents

[goose814]

The Moebius Skipjack and the Greg Sharpe plans for the Skipjack show 5 pair of ballast tank vents, 3 pair forward and 2 pair aft. Also, all the photos of the Skipjack subs I've seen show 5 pairs of vents. However, all references I have show that the Skipjack subs had 6 ballast tanks, 3 forward and 3 aft. So my question is: where is the missing aft pair of vents at? By studying the references I have, it appears that the missing vents may be for ballast tanks 4A and 4B, but I can't find any photos or anything else that shows more than the 5 pairs of vents. Does anyone happen to have any additional information that can enlighten me? Thanks very much for any help.

[tom dougherty]

Re: Question about Skipjack Ballast Tank Vents

Not sure if this helps, but...

[goose814]

Re: Question about Skipjack Ballast Tank Vents

Thanks very much, but I have those references. The issue is that you can see there should be 3 pairs of vents aft but all the photos of this area that I have seen, as well as the Greg Sharpe plans, and the Moebius model show only 2 pairs of vents aft. I have been trying to figure out where that third pair of vents is located. Thanks again.

[steveuk]

I cant prove with clear photo's but I am conviced that MBT vents 4A & 4B are under the end of the turtleback exhaust cover. If you look at close ups of the aft end of the turtleback cover you can see there is a round access panel on each side which would be directly over the vents for maintenance. Also this position ties in with the schematics which have MBT vets 4A & 4B in this portion of the hull. I will try to attach a photo to demonstrate.

[salmon]

I matched up Greg Sharpe plans to the one posted earlier and they seem to match up, here is my crayon drawing:


The colors represent the sets the drawing above shows, what am I missing?
Peace,
Tom

[steveuk]

Those inlets marked yellow on your drawing are MBT 4A and 4B inlets. If you look at the deck directly above those this is where you expect to find the outlet vents. That section of deck directly above your yellow markings does not have any visible vents in photos of Skipjack subs. But that section above your yellow markings includes the rear most part of the turtle back cover. This is where I believe you will find the missing 2 vents..underneath that turtle back cover (that area is all free flooding). That is why you cant see them in any photos. This is my theory about the missing two vents.

[crazy ivan]

My Moebius Skipjack shows a pair of inlet gratings on the underside of the hull directly under the aft end of that exhaust fairing. I know its just a model, but given that this kit was in part designed by a Master Modeler with real life experience in such matters, I would guess it would lend creedence to your theory. Maybe Bill Lambing could shed some light here.

[salmon]

I believe David Merriman collaborated with Moebius on that model, I will ask him. I see where I did not understand, it is the VENTs you are looking for, not inlet. My mind scrambles things so I miss things.

[Ralph --- SSBN 598]

Ballast Tank Vents on top.
Ballast Tank Flood Ports / inlets on bottom.

;^)

[salmon]

It looks like everyone is right. The vent in question was outside the exhaust housing and inside depending on the sub. This information came from Jim, I was told and I believe the hand-drawing originated by Ken Hart.

[steveuk]

wow, great info! Persistence pays off. I am constantly surprised by the differences discovered between sister ships. As with my study researching for Repulse and her Resolution sister ships, each is uniquely identifiable once you get to know them. Just like whales and sharks etc which have slight differences between markings.

So the next question is which one are you going to build yours as?

[crazy ivan]

[ATTACH=CONFIG]3426[/ATTACH]
It looks like everyone is right. The vent in question was outside the exhaust housing and inside depending on the sub. This information came from Jim, I was told and I believe the hand-drawing originated by Ken Hart.

Uh-oh! Looks like my Snook is heading back into the yards for a re-fit. Thanks for that, Tom. More to learn every day!

[bigdave]

Well somebody has to say it.
Looks like you have been snookered again George. . BD

[thor]

You are always good for a laugh, Dave!

[bigdave]

Thanks Matt.
Usually in more ways than one. Lol BD