Virginia class stator question

[Timothy L]

In the attached diagram there is no indication of a stator in the propulsion system. Yet my understanding from descriptions of the class is that a stator is present. What am I missing? Would the stator be directly behind the prop? Thank you for any input.

[He Who Shall Not Be Named]

In the attached diagram there is no indication of a stator in the propulsion system. Yet my understanding from descriptions of the class is that a stator is present. What am I missing? Would the stator be directly behind the prop? Thank you for any input.

Three types:

Pre-swirl stator




Post-swirl stator



Pre and post-swirl stators

[wlambing]

Careful, gents. There are some things that certain entities do NOT want you to know! That is why you don't see them in illustrations and photos (draped tarps). That was my world for many years and it's still very easy to inadvertently get nailed for such things.

[CC Clarke]

Careful, gents. There are some things that certain entities do NOT want you to know! That is why you don't see them in illustrations and photos (draped tarps). That was my world for many years and it's still very easy to inadvertently get nailed for such things.

Well said. Those who know, don't talk. Those who don't know, talk. Until a released photo emerges, speculation reigns supreme.

[CC Clarke]

Even with something that's been in the public domain, the Navy still keeps the ethos where screws are involved. Here's a shot of an admiral (who was our guest speaker) jokingly covering my Parche's screw for a photo shoot recently.

[He Who Shall Not Be Named]

Careful, gents. There are some things that certain entities do NOT want you to know! That is why you don't see them in illustrations and photos (draped tarps). That was my world for many years and it's still very easy to inadvertently get nailed for such things.

As Ellie and I well know!

Near the end of my Naval career, I found myself frog marched by the NIS off the brow of the USS RECOVERY and charged with unlawful disclosure of classified material. Into their black sedan and off we went to Navy Housing. Much of the crew on the main deck and pier taking the drama in. Eye candy for the powers that be.

Entering our house with search warrant presented, the Agents started rummaging through my study, office, and shop.

Meanwhile, this angry little wife of mine got to work in the kitchen preparing a rescue plan, with one of the Agents hovering over her. In no time she graciously shoved plates of steaming, fragrant Island delicacies -- that only hardened Philippina's would smile at -- at the Agents, with the most insincere smile I've ever seen on her face. Stunned by this act of 'hospitality', the NIS goon squad graciously declined the food and made a tactical retreat back to their office. No more heard from the NIS.

(Island people tend to be the nicest humans on this planet... till they're not!)

But the on-board theatrics did the job over time; from that moment on, life in the Navy became a chore, not a joy; suit wearing ass-holes know how to **** you up without employing official punishment.

My hero:



(All charges against me were dropped once I demonstrated that all my studies were done using information well within the public domain).

[Albacore 569]

Here is a public source, if rare now in my library. Published in 1990. It may safely answer the questions. without clear photos. David's description of post and pre swirl are correct. Here is a more detailed answer from 'submarine Technology for the 21st Century by Stan Zimerman published in 1990. A public source - the topics covered then in 1990 all have since come to fruition in present day. Topics of exotic materials, sound proofing, Pump jets, AIP propulsion, Optronic masts etc.

Basically, Post swirl is more efficient but nosier. Pre swirl like you have seen on most or all nuclear submarines are a little less efficient but much quieter. But since nuclear submarines have essentially an unlimited energy source (operationally 15 years and the newest ones 30 years!) the accepted small inefficiently is irrelevant, Quiet operation is everything.

That you never see Pump jets on a non-nuclear-powered vessel should now makes sense. If there is a shroud present - then these are Kort nozzles, not pump jets. Post swirl are more likely to be observed on Torpedoes with their advanced but limited batteries where efficiently is most desired.

[Timothy L]

My thanks to all who responded. Your input is most educational. Sometimes you just don’t know what it is you don’t know! Thank you.

[Albacore 569]

The pump jet feature on our models of the latest nuclear submarines (Captial ships of the fleet) are a problem turning at the pond. Basically, their turning sucks! As maneuverable as a cement truck

I have a new idea that will be incorporated into my French Suffern SSN (French SNA) that i simple and decreet and robust to turn that lamp shade frm a lability to an assent. If it's not scale like, (or i it?..lol) will make th Suffern very maneuverable it is hoped.t at last complete n a regatta maneuverability course. Admittedly also the Models Pump et will need to be a 'post swirl contrary to what ls likly reality. But its discrete!

[SubSteve]

The pump jet feature on our models of the latest nuclear submarines (Captial ships of the fleet) are a problem turning at the pond. Basically, their turning sucks! As maneuverable as a cement truck

I have a new idea that will be incorporated into my French Suffern SSN (French SNA) that i simple and decreet and robust to turn that lamp shade frm a lability to an assent. If it's not scale like, (or i it?..lol) will make th Suffern very maneuverable it is hoped.t at last complete n a regatta maneuverability course. Admittedly also the Models Pump et will need to be a 'post swirl contrary to what ls likly reality. But its discrete!

Looking forward to seeing how this works out. I have hours of stick time on RC tugs with steerable Kort nozzles. They work great. You may also reveal an ability to steer in reverse, my tugs will do figure-8s in reverse.

[Timothy L]

By looking at a stator and prop set, can you determine whether or not it is a pre-swirl or post swirl based on the angle of the blades in the respective component? Thank you