USS Nautilus SSN 571

[feet wet]

Good Day,
I am working on resurrecting a 1/48th Nautilus build that I never quite finished years ago. Now, as then, I am still perplexed by the bow plane arrangement, so here I beg for input. When deployed, did her bow planes, in the neutral position, ie 0 rise/0 dive, deploy to a position 90 to the casing, or did they deploy to a position parrallel to the water surface?
Thanks for the education.
Jonthan

[Ralph --- SSBN 598]

Bow planes deployed in dry dock.

https://www.reddit.com/r/submarines/comments/bklizs/inactivation_of_uss_nautilus_ssn571_in_mare/

The struts seem to be down and touching the hull which would indicate full extension but could also mean disconnected for maintainance.
-------------------
If this is what is holding up your progress, I suggest making the bow planes extend to level with surface and also make them so you can adjust them later to what every you learn about the planes.

[salmon]

Jonathan,
I thought this was discussed on another thread, but the arrangement in the picture Ralph posted was the final extended position as I understand it. There were issues when the planes were deployed to parallel to the water surface. I recall an article that there was a vibration that was occurring while underway during tests, so it was changed to the 30 degree angles in the photo, at that angle, the vibration disappeared.

On your model it may not make a difference, but I would suspect fully extended will give you better control of fine adjustments.
Peace,
Tom

[feet wet]

Ralph and Tom,
Thank you for your input. One reason I am somewhat baffled is that due to the shape of the planes, and the tumble home of the hull, there does not appear to be many degrees of rise available if the planes deployed parallel to the water. Another question that is bothering me is the angle of the bow plane shafts. I would have thought them to be parallel to the water, but the photo appears, to my tired mind, show them passing through the casing at about a 90 degree angle. If the planes deployed so that they were inline with the shafts, then they would form a diheadral and be 90 degrees to the casing.
I fully agree that if they deployed parallel to the water I would have more control, but I also would have to remove a wedge of the planes in order to get any up angle.
Why is this So complicated? If life were only simple...LOL

[Ralph --- SSBN 598]

I looked for the article that Tom was talking about.
I too remember something about flutter when level.

In the drydock photo, when enlarged, a safety cable can be seen holding the plans from dropping any more.
This makes me think the plans may be disconneted under the deck.

Now I took your photo and enlarge it as well.
I see the planes hinge has no planes past the inge towards the hull.
If the planes are lowered, there will be a large gap between the base of the planes and the hull.
This may be enough to allow the planes to rotate without hitting the hull.


I did not scale the photos so I am nut sure of the gap distance but it looks like the plpanes cold rotate 30 degrees and not hit the hull.

I am surprised of the lack of photos of the 571 with planes deployed.
Lot of models with the planes in both positions but no real photos.

Other submarines have the bow planes hinge recessed so the plans extend past the hinge.

[Ralph --- SSBN 598]

Seems I got 2 post for one.

[Ralph --- SSBN 598]

Looks more like 3. ?

[X Bubblehead]

Seawolf had the same bow planes arrangement. Our planes were parallel to the hull when extended. We didn't deploy them until just before we pulled the plug since the wave slap on the surface was horrendous and shook the entire torpedo room.

The MINSY photos (I was there then) used cables to hold the planes at that angle during hull preservation which was occurring at the time. Maybe a former crew member can chime in with better info. I live near the Nautilus and will get a definitive answer the next time I'm giving a tour. The Nautilus blueprints I have show extended parallel bow planes.

CC

[Ralph --- SSBN 598]

CC, that is a great offer.
The rest of can only guess from what we see.
Having first hand information would put all the questions to bed.
Thanks.
Ralph

[PaulC]

For what it's worth, I was at the museum in 2018 and toured Nautilus. There was a submariner stationed in the hut on the bow and I asked him specifically about this. He did not hesitate to state that the planes when extended for dive were parallel to the water and not angled out from the casing as shown in the drydock photo.

[drschmidt]

In their original configuration the bow planes were extended parallel to the water (horizontal). In the test runs the boat experienced quite severe vibrations in the bow section, so severe that there were cracks in the hull. These vibrations disappeared when the planes were tilted upwards. So in the final configuration the planes were perpendicular to the hull and not parallel to the water.

Check my Nautilus build fpr reference: https://subcommittee.com/forum/showt...nautilus+final

[feet wet]

Thank you all for your input.
I wonder if the vibrations that drschmidt refers to wee caused by the geometry of the hull and planes. That same geometry would seem to explain why the planes would be more effective if their extension was limited to bringing them perpendicular to the casing. I am curious though. does "original configuration" refer to as launched? And does "final configuration" refer to as deployed?
Drschmidt: Wonderful build.I only wish that I has studied CAD many years hence.

[X Bubblehead]

I will continue to search for a definitive source for the bow planes orientation being modified from planar to angular to remedy the laminar flow noise that Nautilus suffered from while running her first trials. I may have to hit the Nautilus museum to nail this down. As a kid, my Dad's boss in Japan was Adm. Eugene Wilkinson, the first CO- He could have put this issue to bed!

Bow planes should not cause vibration while submerged when deployed parallel to the hull. I do know the stern swash plates on the end of the turtleback and longitudinal limber holes along the superstructure (except for a few on the bow) did not last very long. The high noise was said to be produced aft of the sail, though it was loud enough in the torpedo room to make the crew yell to be heard at higher speeds. You know they jumped all over that!

Because Nautilus and Seawolf were built by the same yard almost simultaneously, (Seawolf took longer to complete due to her more sophisticated liquid sodium plant) they shared many other components. Her bow planes and rigging gear look identical. Both bows and superstructure were very similar in their geometry above the waterline, though the Wolf had a larger bow buoyancy tank from a comparison of my piping tab. The S-Girls stowed their planes inboard, which had to be a plus when surfacing through the ice.

Neither boat lasted long as front-line attack boats due to their inherent high self-noise, which was significantly reduced with the Skipjack class. Seawolf was so noisy we had SHT (anechoic coating) applied aft of the RC in 1981. Subsequent acoustic trials at Carr Inlet proved its effectiveness, Nautilus was a show boat due to it's historical significance and was assigned to testing to free up more capable SSNs to trounce Ivan later in her career.

--As for the technical accuracy of the topside watches, the last time I was aboard to give a tour to some out-of-town visitors, the watch saw my Seawolf hat and asked me how they loaded torpedos. Once he told me what boat he had qualified on, (a Trident) his unfamiliarity made sense. They load weapons vertically, via crane though the forward LET, (Logistics Escape Trunk) rather than at an angle through the exit of the forward escape trunk which faces aft. I spent fifteen very enjoyable years working pier-side at Trident Refit Facility Bangor after leaving the Navy. The LETs were a major innovation, making the movement of parts on and off the boats via an 8' diameter hole extending thru three levels a giant leap forward.

TBD,

CC

[X Bubblehead]

A little more info but inconclusive as to the fix: http://the.honoluluadvertiser.com/ar.../ln/ln05p.html

Excerpt:

Still, there were growing pains.

A year and a half after the Nautilus took to the sea, it was dry docked because it had been experiencing vibrations at higher speeds. Initially, the problem was thought to be minor.

"We had this high-speed vibration when we ran at 20-plus knots," said Engle. "It was a light shaking — nothing horrible. But you'd sit in the ward room and see ripples in your cup of coffee. So, you wonder what's going on."

John Craven, soon-to-be chief scientist of the Navy's Special Projects Office at the time, led a team that tested the sub at sea. Those tests confirmed his fears that a design flaw in the ship's ballast tanks could have sent the Nautilus crashing to the bottom of the ocean at any moment.

"It would have sunk," said Craven, 80, of Honolulu, who compares the importance of Nautilus to the Apollo Moon landing. "Finding out what was wrong was the high experience point of my life."

[drschmidt]

As built -> horizontal, deployed -> tilted upwards. Got that info from a Nautilus sailor via a Nautilus memorial website.