Protecting Canada by Sub (split fm Canada's New, Liberal, Foreign Policy)

[Kirkhill]

I always enjoy this type of conversation.  I learn (sometimes I am schooled).

With respect to time on station -

Gliders can stay at sea for very long periods as they don't use any fuel for propulsion.  They fill bladders with gas to lower their density, increase their buoyancy, and float to the surface.  Then they blow tanks, become heavier, denser, less buoyant and let gravity work. As they sink they can use their wings to fly against the currents.

http://www.ioos.noaa.gov/glider/welcome.html

For the powered AUVs, the autonomous ones, a Canadian firm, ISE has built and deployed a 7 m, 2000 kg unit (Arctic Explorer) that mapped 1000 km under the ice in a single 10 day sortie.

http://www.ise.bc.ca/auv.html

And if the Boeing video on their Explorer (posted by Thucydides upthread) is to be believed, their Explorer is intended to have an endurance of months, similar to the endurance of the gliders.

I doubt if these things are for fast transit but instead for slow patrols

 

[a_majoor]

In any rational discussion on submarines, there would be a minimum of 8 boats, just to ensure there is always one on patrol per coast and having one extra per coast to "surge" or apply to an expeditionary force when needed. Still hardly adequate, but probably better than nothing. 12 would probably be closer to what we "really" need, but given defense priorities and the limited amount that the government and people are willing to spend, this is likely a non starter. The other aspect, as mentioned, is the boats would be part of a team effort, so "X" subs should also teamed up with "Y" surface ships and "Z" LRPAs. For Canada, this would be an extraordinary expense.

The Boeing vessel is an example of the sort of tool which can supplement subs. I see things like that and the seaglider or waveglider as being useful in extending the "reach" of the fleet, patrolling for long times and distances and acting as sensors to vector other assets via the various means that Chris has mentioned upthread. Even a relatively small ship like the "Kingston" class should be able to tender and observe several UUV's. Of course there still need to be assets which are capable of actively investigating and if need be prosecuting contacts, and having a manned vessel provides the all important person in the loop to make the "shoot/no shoot" decisions.

 

[GR66]

I wonder if something like like a seaglider or waveglider would be capable of trailing a towed array sonar?  I'm guessing the extra weight and drag would impede their method of propulsion.  I can see a powered AUV acting something like a mobile SOSUS line though.

 

[Eye In The Sky]

I would be interested in hearing the thoughts on this stuff from someone who is an acoustician and understands the ASW game far better than I do.  There are a few on this forum who have served under and above the water...maybe they'll weigh in.

A lot of this would be centered around water.  From my basic introduction to oceanography, 3 things affect how sound travels (and where it travels...) through water;  salinity, temperature and pressure.  I'll assume there is a completely different set of considerations for areas like up north, but I don't understand them enough to do more than mention them.

But I'll wager that this type of info would have a considerable effect on the cap's and lim's of systems being discussed...

 

[Kirkhill]

I would be interested in hearing the thoughts on this stuff from someone who is an acoustician and understands the ASW game far better than I do.  There are a few on this forum who have served under and above the water...maybe they'll weigh in.

A lot of this would be centered around water.  From my basic introduction to oceanography, 3 things affect how sound travels (and where it travels...) through water;  salinity, temperature and pressure.  I'll assume there is a completely different set of considerations for areas like up north, but I don't understand them enough to do more than mention them.

But I'll wager that this type of info would have a considerable effect on the cap's and lim's of systems being discussed...

And I wouldn't be at all surprised if, as in your game EITS, that those who do know probably won't be saying much here. 

 

[Eye In The Sky]

I am sure he could generalize it so it is 'ok' for here.  :nod:

 

[a_majoor]

I wonder if something like like a seaglider or waveglider would be capable of trailing a towed array sonar?  I'm guessing the extra weight and drag would impede their method of propulsion.  I can see a powered AUV acting something like a mobile SOSUS line though.

Maybe not a full towed array, but I can imagine several of these devices towing a very small array and the control vessel integrating the input from multiple arrays distributed in a "box" formation rather than a single linear array.

 

[Baz]

I would be interested in hearing the thoughts on this stuff from someone who is an acoustician and understands the ASW game far better than I do.  There are a few on this forum who have served under and above the water...maybe they'll weigh in.

A lot of this would be centered around water.  From my basic introduction to oceanography, 3 things affect how sound travels (and where it travels...) through water;  salinity, temperature and pressure.  I'll assume there is a completely different set of considerations for areas like up north, but I don't understand them enough to do more than mention them.

But I'll wager that this type of info would have a considerable effect on the cap's and lim's of systems being discussed...

I was an acoustician (CH-124B) HELTAS, and I've also written code to do passive, active, and prediction; I can help some.  Everything below is open source and I can provide links if you want to read; well, maybe, depending on how much I care

You are, the speed of sound is determined by salinity, temperature, and pressure; the path of water through sound is determined by the speed changing at different depths.  It will curve towards lower speeds.

However, something else is going to happen: its going to hit the top (surface), and except in pure blue water (ie really deep), it's also going to hit the bottom.  Depending on a whole lot of stuff (to which you can add ice in this case) some will bounce and some will reflect.

As well, it will be attenuated... and this is where frequency becomes important: lower ones attenuate less (http://www.mathworks.com/matlabcentral/fileexchange/37689-seawater-acoustic-absorption-calculator).  It's also easier to put more power behind lower frequencies.

So, in the deep ocean, sound will refract down at first, but then the increasing depth cause increasing speed and it refracts back up.  It then either bounces of the surface or refracts back down, etc, etc...  if it is refracting around the point where sound speed is the lowest then that is the deep sound channel and you can get huge ranges at low frequencies (less attenuation).  Of course, every noise maker in the ocean is also getting huge ranges, so it is harder to pic signal from noise...

However, that doesn't describe the arctic... in most places the deep sound channel won't exist (even leaving out weird surface effects due to fresh water melting and how cold it is).  So all that power may go straight into the bottom, and then all you get is bottom reflection mixing in with your reverb (which is another limfac for high power low freq by the way)...

None of this would determine whether anything you want to do is possible or not (I know some people at DRDC-A that have worked these types of questions), but it would be a consideration (a very important one) for how you would do it.

By the way, somebody may have said it and I missed it, but there are also floating trailing wires...

 

[blacktriangle]

Even if a revised defence policy were to focus more on "protecting the homeland" and less on expeditionary operations, I feel submarines should still be a no brainer. SSKs would obviously be an easier sell to Canadians than their nuclear equivalents. A modern fleet of subs, with an increased number of AOPS and a small fleet of modern Frigates would probably protect Canada adequately when coupled with sufficient LRPA, MH, and fighter coverage.

 

[PuckChaser]

Problem is, we need subs that are operational, not constantly under refit or repair or restrictions to depth. If the policy says subs, we need to stand up the project now to purchase 5-6 SSKs, and look at options to piggyback into another countries' order as long as it meets the under-ice requirement we'll inevitably have. We've recently signed an ISSP contract for 15 years, that gives us the normal procurement cycle to have replacements in the fleet by the time that contract is finished.

 

[blacktriangle]

Problem is, we need subs that are operational, not constantly under refit or repair or restrictions to depth. If the policy says subs, we need to stand up the project now to purchase 5-6 SSKs, and look at options to piggyback into another countries' order as long as it meets the under-ice requirement we'll inevitably have. We've recently signed an ISSP contract for 15 years, that gives us the normal procurement cycle to have replacements in the fleet by the time that contract is finished.

Agree 100%. I'm definitely not going to hold my breath for any form of coherent defence policy. Ditto for a proper procurement system.

 

[Underway]

Problem is, we need subs that are operational, not constantly under refit or repair or restrictions to depth. If the policy says subs, we need to stand up the project now to purchase 5-6 SSKs, and look at options to piggyback into another countries' order as long as it meets the under-ice requirement we'll inevitably have. We've recently signed an ISSP contract for 15 years, that gives us the normal procurement cycle to have replacements in the fleet by the time that contract is finished.

Well the Aussies are buying and building these nice Shortfin Barracuda.  On paper they look very capable and for a conventional submarine.  Article here for a comparison of them to the Collins.  I think the range and endurance requirements fit into what Canada may want.


*edited to fix links*

 

[Colin Parkinson]

My guess the Aussie contract will start facing questions by the 5th sub as governments change directions, that would be 10-12 years from now and good time for Canada to say 'hello we are looking for subs". apparently the Aussie plan is sort of a; subs 1-5 go into service, 6-9 come into service and 10-12 replace 1-5 who are retired.

 

[Underway]

My guess the Aussie contract will start facing questions by the 5th sub as governments change directions, that would be 10-12 years from now and good time for Canada to say 'hello we are looking for subs". apparently the Aussie plan is sort of a; subs 1-5 go into service, 6-9 come into service and 10-12 replace 1-5 who are retired.

I doubt that, (barring the questions part).  South Australia is loosing a large number of manufacturing jobs and there a number of seats at play in Parliament.  Critical ridings need their jobs.  50 billion dollars is a lot of investment into the local economy.  What I did like was the deal structure that was initially worked out but was not taken.  The French proposed building the first two subs in France with half Australian workforce.  By then the facilities for building the rest would be up and ready in Australia.  Then the those workers would be moved back to Australia and the rest of the boats would  be finished.  It would have advanced the timeline significantly and educating Australian workers in how the boats are to be built.  Its a model that could be looked at for any future Canadian sub project.  I mean we already have a shipyard that speaks French and Davies/Irving will be busy for a long time with all their NSS contracts.

 

[Colin Parkinson]

that would make so much sense, so it's unlikely to happen.

 

[Underway]

Sub planning and purchasing articles from the Maritime Engineering Journal 2014:

links:  Part 1 starts on page 12 and Part 2 starts on page 10.

This discussion now changes with the Shortfin Barracuda purchase by the Australians.

 

[Oldgateboatdriver]

It doesn't change his penultimate conclusion that:

"A MOTS submarine, built overseas but maintained in Canada, is the lowest-risk, lower-cost option that will deliver an operationally relevant future submarine capability."

But it actually invalidates his view, at the time correct though, that:

"Historically, Canada has sought long-range, high-endurance submarines for expeditionary operations.  The current MOTS marketplace does not have a clearly identified fit for these demanding requirements."

 

[Underway]

It doesn't change his penultimate conclusion that:

"A MOTS submarine, built overseas but maintained in Canada, is the lowest-risk, lower-cost option that will deliver an operationally relevant future submarine capability."

But it actually invalidates his view, at the time correct though, that:

"Historically, Canada has sought long-range, high-endurance submarines for expeditionary operations.  The current MOTS marketplace does not have a clearly identified fit for these demanding requirements."

Agreed.  The Shortfin will soon (2years?) be a MOTS or at the very least a "well into the design/development stage" option for the RCN.  The Australian requirements are almost exactly the same as the Canadian requirements he lists.  Perhaps a build in Australia option...  His timelines are not surprising either.  I wonder if a build the majority overseas with the finishing touches in Canada option would be valid, though subs need much of their equipment added during the build process vice after (can't just add weapons/sensors after most of the hull is built...).

 

[Oldgateboatdriver]

You can add weapons or sensors after the hull is built, but it is complex and expensive.

We certainly added sensors to the "O" boats during the SOUP refits, and we certainly changed the weapons system on the Windsor's after we got them from the UK (replaced tubes and launch system from Tigerish to Mk-48's).

 

[Colin Parkinson]

Our subs will be long in the tooth by the time there is room to build for us, having them built in France might be difficult as only the Aussies will be fitting US weapons into their.