Not anticlimactic to for the outside observer, that’s for sure. Great video, lotsa pictures.
In a way the most interesting part to me was how the sub shimmied a little bit as it surfaced. Like…it’s actually on water.
If there is any danger, I would surmise it has to do with the crewmen inside potentially banging their heads or otherwise getting knocked about as the submarine is breaching the water and then landing again, not any real damage to the submarine components themselves.
This is an older thread, and I’ve already chimed in elsewhere within it, but isn’t one big difference between the (now-defunct) Typhoon’s mission in the ice and the US’s is that the Typhoon might have been required to bust through the ice quickly in order to launch its ballistic missiles? That seems like something that they’d at least want to practice once or twice to see if, e.g., pushing up through the ice fast busted up their missile tube covers or the like. Whereas it’s difficult for me to think of a reason that a US sub in a non-casualty situation, would need to get through the ice ASAP. Although, thinking of stuff like a fire in the crew spaces while under the ice…(shudder).
Anyway I think, (and yeah, anyone who knows, couldn’t say) that such ballistic missiles can’t make it through the ice cap. And that one of the possible deployment strategies for the Typhoon/Delta IV/Bars etc… Russian SSBNs was to deploy under the ice, while relying on things like ELF or seabed placed repeater to tell them when to get up and shoot?
Since we’re maneuvering submarines in reckless and potentially dangerous ways…
How about barrel rolls and immelmans? Presuming something suitably psychoactive wound up in the evening mess and everyone on board thought this would be a way rad idea.
Since I don’t “know,” I can say that I highly doubt a submarine launched ballistic missile could get through any substantial amount of ice. Ballistic missiles are not made of super tough stuff. They are meant to do their job of getting ejected and flying, not to burst through 12 inches of solid ice. Their whole structure would have to be built from the ground up to do that, and they would have to be really heavy.
Why must it have internal strength members? A cylinder is a very strong structure. Airplane bodies are cylindrical, and they usually don’t have internal structures.
What, do you think that video is CGI?
Not a chance.
All of the propulsion plant stuff is built on the idea that liquids stay at the bottom.
Even something as simple as the design of the oil sumps would get you.
More profound would be the problem of condensate in the hotwell below the main condenser suddenly raining down upon the steam turbine blades.
Also interesting would be the pressurizer steam bubble in the reactor plant finding its way into the reactor.
These are just a sampling of the “barrel roll” problems that would finish off your sub, or at least void the warranty.
While I’ll be the first to admit that the boundaries of my ignorance concerning nuclear subs borders on infinity, I was actually proposing doing this with a diesel sub operating on batteries. Sorry for not making that clear.
Can the planes even function like ailerons? I don’t know if they can be rotated at different angles to generate roll.
And diesel engines don’t like being inverted, either.
Let’s face it. You have to design a lot of systems very specifically – and expensively – to be invertible. If there’s no mission reason to do it, why would the boat’s designer waste the design effort and cost?
As a navy surface nuke, I know nothing about diesel subs or subs in general, but I am quite familiar with naval vessels: on any ship there are substantial quantity of tanks and reservoirs for everything from fuel to potable water. All of that stuff is going to be in the wrong place.
Now, for my sub ignorance: are those batteries even sealed? If they aren’t, then they will simply empty their contents, causing bad things to happen.
Also, aren’t the inlets for the various buoyancy tanks at the bottom, with a bubble of compressed air at the top? Any air left would escape mid-roll, sending the sub deeper.
In an airplane barrel roll, the centrifugal force cancels out the “negative” gravity and then some. Everything and everyone on the plane still feels “down” is towards the floor of the plane. That’s why airplanes that aren’t designed for aerobatics can still do barrel rolls.
There’s no way a submarine could move & roll fast enough for centrifugal force to cancel out gravity.
Okay. I misspoke. The maneuver I was thinking of is actually called an aileron roll. Just spinning 360 degrees along the same flight path. I would think that angling the planes on one side up and the other side down would be enough to cause that particular acrobatic chicanery to happen.
re: sealed batteries. I would think they would have to be because otherwise they would always be venting acid gas which would be a bad thing in and of itself.
Again, not possible, if for no other reason than the port & starboard hydroplanes are not independently controllable. In other words, the bow/fairwater planes move up and down together, as do the stern planes.
They could certainly be designed to be independently controllable, but there’s no reason for them to be so.
I have a great deal of experience in inspecting submarine batteries, which is required to be conducted immediately prior to charging the batteries on a submarine. (This is every couple of days, and the inspection takes about an hour.) Anyway, the lead-acid batteries used are not sealed. They are well-vented with a splash cap/spark arrestor.
Under normal operation, lead-acid batteries don’t vent acid gas. Heaven knows I’ve spent enough time crawling around in battery wells. The electrolyte in the batteries is sulfuric acid, which is quite soluble in water and stays in solution. Note that the technology here is the same as is used in car batteries.
What does vent (at times) is hydrogen gas, which can be produced when batteries are charged and/or discharged too quickly, or are overcharged. In this case, you want the batteries to vent, so that the hydrogen gas does not build up to pose a fire/explosion hazard. (The submarine atmosphere control system is designed to handle small amounts of hydrogen gas via the CO/H[sub]2[/sub] burners.)
Chlorine gas can also be produced if seawater were to enter the battery well (via electrolysis of the salt water), but in that case, you’re clearly already having a bad day. :eek:
Exactly.
When comparing the acrobatics of an airplane with the maneuverability of a submarine, you have to keep in mind the relative masses and speeds involved, and the fact that moving through air is far different than moving through water, with liquid water being approximately three orders of magnitude more dense than air.
Small stunt planes have a mass of a ton or so, and move at speeds of a few hundred knots. Fighter jets have a mass that is an order of magnitude larger (i.e. a few tens of tons) and move at correspondingly higher speeds (high hundreds to a thousand knots or so).
Military submarines have a mass of several thousand tons (2-3 orders of magnitude more massive than the planes discussed above), but move at speeds of a few tens of knots.
This probably ventures into classified territory, but can/do military submarines have autopilot-type governors built into their systems that automatically negate orders or maneuvers that would be hazardous to the submarine or its crew? So for instance, the sub can be programmed to not go below its never-exceed depth, so as to prevent someone from carelessly pushing the control yoke forward when the sub is already at depth and at high speed, and thus potentially going into dangerous depth within seconds.
And, of course, to also prevent the sub from flipping upside down, as mentioned above.
Mission accomplished and ignorance fought. Thanks for your input!
It’s military hardware, built to withstand punishment and continue operation, even after many parts of the system have sustained battle damage. Some things will have hard limiters on them (such as boiler safety valves, and stops on guns preventing strafing the bridge) but for the most part there are documented engineering guidelines as well as monitors, alarms, and all kinds of stuff to help keep you from doing something bad, but if you absolutely must do so, you can simply silence the alarms and continue doing the bad thing.
For example, one of the most urgent situations on a ship is a loss of lube oil in the main engines, requiring immediate stopping of the shaft in order to avoid permanent damage–this condition merits the loudest and most annoying alarm: a wailing siren. Nevertheless, you can imagine a military situation where it is better to trash the bearings and (very very expensive and huge) gears for a short term gain.
A sub can’t flip upside down; too much weight near the bottom and the control surfaces are far too small.
There are certain automatic protective systems on the sub, but little that would stop the crew from destroying the sub if they chose to do so on purpose. I won’t discuss the control system that the planesmen use.
Ranb
I realize Dr. Strangelove’s post is four years old, but I thought it might be worth clarifying that the damage that caused Chopper’s retirement was much more likely to have occurred during her initial out-of-control descent than during her emergency surfacing operation.
Her stern reached nearly twice her test depth and her bow was about 2.5 times her test depth. Pressure increases linearly with depth, so her hull was subjected to over twice the compressive stress she was ever expected to see.
The Wikipedia quote makes it sound like both the descent and rapid surfacing caused damage. But in all probability, it was the overpressure that forced her retirement.
Also, more recent posts make it clear that the occasional emergency blow is fairly safe.