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New Canadian Shipbuilding Strategy

  • Thread starter Thread starter GAP
  • Start date Start date
I could be wrong (happens to me now and then) but if I recall correctly, there was an intention that the existing Combat Management System (CMS) on our frigates would be 'robust' enough to be ported over to other classes of vessels, such as the CSC.

Obviously, sensors would be different, and weapons, but the core program I think was intended to be common between platforms.

That said, looking specifically at Nav systems, we have much in common between platforms, using the same SHINNADS, RLGNs, and NDS systems.

For reference though, installing the NDS cabinets (Navigation Distribution System) as a retrofit/upgrade took over 2000 hours, plus the cost of the cabinets.  (per ship) and while this was done on some ships concurrently with the MLR, it was not an MLR project.

NS


 
hamiltongs said:
Gearboxes and powerplants - Not at all. You won't find civilian ships with the complex CODAG sort of arrangements that are common (and necessary for redundancy) on warships.

Hull - Nope. Naval hulls these days are optimized for radar cross-section reduction, which isn't even remotely a civilian consideration.

Navigation gear - The nav systems on a warship need to be integrated with the combat systems, which for a variety of reasons means they need to be developed as military grade from scratch.

Engine rooms and mechanical services - Again, these arrangements tend to look very different on warships due to the need to optimize for survivability (so, a higher degree of compartmentalization and redundancy, etc).

Platform Management Systems - The civilian requirement doesn't have to address the need to "float-move-fight": naval systems are heavily geared towards shipboard fire fighting and damage control. Where civilian ships sometimes to use the same IPMS as military ones (for example, the former CAE/now L3 system), that's because the systems were designed specifically for military use and can be "down-graded" to fit the civilian requirement.

And now I needs must proceed very carefully here because I was out of my depth when I fired off my first blast.

But.  Always up for a challenge.

"Gearboxes and powerplants - Not at all. You won't find civilian ships with the complex CODAG sort of arrangements that are common (and necessary for redundancy) on warships."

Which may perhaps explain the move to diesel-electric plants with podded propulsors?  And the tendency to focus on diesel engines rather than gas turbines?  Given a choice of turbine or diesel for tanks the Brits, Jerries, Italians and French, and the Russians, all opted for Diesel.  Only the Americans felt there was an advantage in the turbines. 

As to mechanical gear boxes and complex linkages - industry has moved away from mechanical variators and gear boxes to frequency drives precisely because they are simpler to install, easier to locate, cheaper to maintain, less likely to fail, and easier to replace.  Not to mention easier to maintain water tight even in an NEMA 6P environment.

"Engine rooms and mechanical services - Again, these arrangements tend to look very different on warships due to the need to optimize for survivability (so, a higher degree of compartmentalization and redundancy, etc)."

Again I would point out the benefits of the hybrid diesel-electric configuration in this regard, especially as it is much easier to seal a power line transiting a bulkhead than it is a rotating shaft or even a pipe.

And the podded propulsion systems don't seem to be going away.

"Hull - Nope. Naval hulls these days are optimized for radar cross-section reduction, which isn't even remotely a civilian consideration"

I would differentiate between hull design and hull construction.

I take your point about the design parameters - but the shape of the hull doesn't seem to be a major problem for civilian yards, either above or below the waterline.  And the issue I am addressing is the constructability of the vessel and ability to contract experienced yards to do the work.

Here is one company's gallery of commercially available hulls.  http://vardmarine.com/vessel-gallery/


"Navigation gear - The nav systems on a warship need to be integrated with the combat systems, which for a variety of reasons means they need to be developed as military grade from scratch."

"Platform Management Systems - The civilian requirement doesn't have to address the need to "float-move-fight": naval systems are heavily geared towards shipboard fire fighting and damage control. Where civilian ships sometimes to use the same IPMS as military ones (for example, the former CAE/now L3 system), that's because the systems were designed specifically for military use and can be "down-graded" to fit the civilian requirement."

Taking these two together I think you overcome your Navigation objection in your Platform Management objection.  You say that they only reason the IPMS systems are available is because they were developed for military standards and then derated to meet the civilian world.  Something like a Cray computer perhaps?

The point is that the same technology is now available for both civilian and military platforms. And with respect to navigation, are your positioning and situational awareness needs (exempting aircraft) any greater than an offshore survey vessel, a cable layer, a trawler, or a semi-submersible rig?

Finally, with respect to Navy Shooter's comments about the portability of the Halifax Modernization I believe that that has already be demonstrated by the selection of the same system for the New Zealand frigate upgrades.

http://www.lockheedmartin.ca/ca/what-we-do/naval-combat-management-systems.html

A different ship, with different sensors and weapons but the same combat management system provided by Lockheed.


Again,  no expert me but I try to stay informed.

Looking forward to an educational rebuttal.  [:)



 
Chris Pook said:
Looking forward to an educational rebuttal.  [:)

Ah! C'mon Chris ... You had to say that. You know, just KNOW, that I have to answer that now !!!

But I'll answer a part of  GR66's post first:

GR66 said:
I guess what I'm getting at, is it possible to choose a series of proven systems (the Gearboxes and powerplants from this ship, the Navigation gear from that ship, the mechanical services from this ship, and the Platform Management Systems from a different ship) and shift all of the design and development issues strictly into the hull design and systems integration?

What GR66 suggests is obviously done to a large extent, even for warships. Look at the Halifax's: The GE LM2500 gaz turbines were not invented and built a special way just for the class, and neither were the Pielstick diesel engines. But those type of engines are not "off-the-shelf" items. GE does not build its turbines on an assembly line and then put them in a store room until they sell them. They build when they have an order; same for large diesel engines. So they are still "one build" items and cost you full price wether the design is pre-existing or not.

Same for the gearboxes, really. They, individually, are from existing designs. The problem, wether in a CODAG or CODOG configuration, is integration of all these sets of gearboxes through the complete power curve. This is done through a very complex set of electronic controls over gears and clutches and shafts, etc. This is where the money goes and it has to be done every time you deal with a different hull configuration and ship size, even if you use the same power plant/gearbox combination.

To give an example of what I mean here, but over simplifying for illustration purposes - so please no crucifixion based on missing details or not quite perfect explanation - take the following: The frigate is ordered from cruising at ten knots to 30 knots, unexpectedly. It had been running on diesel with the GT's down (you don't keep the GT's up when not using them otherwise, what's the point of  cruise engine). Now you obviously don't start the GT's, de-clutched, then de-clutch and shut the diesel, then clutch-in the GTs. As the levers on the bridge are pushed forward, the GTs come up and progressively start to provide power to the shafts while the diesel engine progressively ceases to transmit power, so that overall, the ship seamlessly accelerates through to 30 Kts. This gradual switchover occurs aver a portion of the power curve, near the maximum power of the diesel and the medium power of the GTs. but it must happen in such ways that the GTs much greater power is not fed back into the Diesel's gearing so that the competing forces would break the gear.

BTW, there are no such requirements for merchant ships. Most of them are single engine with single gearbox to a single shaft, and even those with multiple engines and screws usually have separate engines to separate shafts each through their individual gearbox. Not so warships, where a single GT could just as easily provide the power to both shafts - yet another level of gearing complexity, usually controlled through electronic systems.

So the short answer GR66, is that we already do what you propose, but it doesn't save money on the actual piece of equipment, and the main problems arise from integration of these systems into a whole.

Now on to my good friend Chris.  I'll put my comments in yellow into his text:
Chris Pook said:
"Gearboxes and powerplants - Not at all. You won't find civilian ships with the complex CODAG sort of arrangements that are common (and necessary for redundancy) on warships."

Which may perhaps explain the move to diesel-electric plants with podded propulsors?  And the tendency to focus on diesel engines rather than gas turbines?  Given a choice of turbine or diesel for tanks the Brits, Jerries, Italians and French, and the Russians, all opted for Diesel.  Only the Americans felt there was an advantage in the turbines.

And given choice, the Brits, Jerries, Italians, French, Russian and Americans all opted for Gaz turbines for the upper end of the power requirement for their new frigates and destroyers. The upper power curve requirements for warships are just too great. Look at your favourite country (the only one that opted for all diesel for a frigate, but while acknowledging that they miss on the acceleration in the upper speed range as a result) Denmark: Absalon 16.6 MW of power for 24 Kts to Iver's 32.8 MW for 30 Kts. The last 20% of speed costs you as much power as the first 80%. As regards pods, no one uses them for the frigates/destroyers. Those countries going "all-electric" propulsion, like the Brits and the Americans, use electric motors geared through actual shafts with standard screw. Azipods have serious speed limitation as a result of their design, so they are used in warships that don't need higher speeds but great manoeuvrability, such as mine warfare crafts and amphibious warfare vessels.  

As to mechanical gear boxes and complex linkages - industry has moved away from mechanical variators and gear boxes to frequency drives precisely because they are simpler to install, easier to locate, cheaper to maintain, less likely to fail, and easier to replace.  Not to mention easier to maintain water tight even in an NEMA 6P environment.

Don't know which industry you refer to. I am not aware of any industry where they have to deal with the integration of power from various source the way that CODAG, CODOG, COGOG or COGAG does.

"Engine rooms and mechanical services - Again, these arrangements tend to look very different on warships due to the need to optimize for survivability (so, a higher degree of compartmentalization and redundancy, etc)."

Again I would point out the benefits of the hybrid diesel-electric configuration in this regard, especially as it is much easier to seal a power line transiting a bulkhead than it is a rotating shaft or even a pipe.

Partially agree: Electric propulsion makes it easier to compartmentalize the power plant. But not limited to diesel. Even with Integrated Electric propulsion, to which the UK (type 45 and Queen Elizabeth) and the US are moving (Zumwalt), you need the massive power of GT's for combatant warships.

And the podded propulsion systems don't seem to be going away.

They haven't even made it in for surface combatants, as discussed above.

"Hull - Nope. Naval hulls these days are optimized for radar cross-section reduction, which isn't even remotely a civilian consideration"

I would differentiate between hull design and hull construction.

I take your point about the design parameters - but the shape of the hull doesn't seem to be a major problem for civilian yards, either above or below the waterline.  And the issue I am addressing is the constructability of the vessel and ability to contract experienced yards to do the work.

Actually, there are two points here: First, merchant ship's hulls are basically one big square box with a slightly more pointy end at the front and and slightly tucked-in ass. On top of it you put the seaman's residence, which is just a big square box. Warship hulls are much  more complex in shape and therefore in construction, because of the need for stealth (above water) and noise reduction (below water). Moreover, and this is the second point, Merchant ships are not built for speed in all sea states and resistance to external shock and forces (usually through flexibility). Warships are, which is why they are built from a different type of steel, high tensile one, than the steel used for merchant ships, and contrary to Merchant ships, where a small slip in welding letting a drop of water here and there is no big deal, warship welds are to be perfect and are, as a result, all usually x-rayed for precision during construction. The welding is different and experience in one doesn't mean experience in the other.

Here is one company's gallery of commercially available hulls.  http://vardmarine.com/vessel-gallery/

No, it's not a gallery of hulls "available". The gallery has two things: Some are photographs of ships, which means "look, I've built and sold that ship to someone - so if you want exactly the same one, I have the plans and can build it from scratch for you", but it is still to be built and at the same cost as the first  + inflation, and it has drawn pictures of some ships, which means that they have never built such ship, like the look and concept, but if you like them and want one, they have to start from scratch to draft the plans and build it. The only company that builds and keeps "basic" "warships" (I mean the hull, machinery and superstructure, but not the finishing or any weapons/electronics) is Damen, which keeps - in view of its popularity - a small number of pre-built bare-hulls for their STAN 4207 patrol boat.

"Navigation gear - The nav systems on a warship need to be integrated with the combat systems, which for a variety of reasons means they need to be developed as military grade from scratch."

"Platform Management Systems - The civilian requirement doesn't have to address the need to "float-move-fight": naval systems are heavily geared towards shipboard fire fighting and damage control. Where civilian ships sometimes to use the same IPMS as military ones (for example, the former CAE/now L3 system), that's because the systems were designed specifically for military use and can be "down-graded" to fit the civilian requirement."

Taking these two together I think you overcome your Navigation objection in your Platform Management objection.  You say that they only reason the IPMS systems are available is because they were developed for military standards and then derated to meet the civilian world.  Something like a Cray computer perhaps?

I would not quite go so far as Hamiltongs on this point, you don't always need to re-invent the wheel, but - I believe what he had in mind is the following: As regards navigation systems, think about it in Army terms. Lets say that we decided that from now on Arty F.O's would call in their strike embedded with the front line infantry using an iPad. You would probably say that the iPad has to be able to be dropped in the mud or water, stepped on accidentally with combat boots, shot at with light weapons, etc. Apple doesn't make that iPad, but you could put an iPad software and processors in a portable box that would resist all that. That is what the civilian navigation systems on warships also have to face, thus they must be built into, to quote Ford, "military grade" casings and boxes.

As for the IPMS systems, again here, no need to start from scratch, bu the analogy is not to buying a computer, but to buying software that needs adaptation overtime. The concept is closer to buying Oracle for your financial and manpower management in large organization: Oracle already has a system drafted and developed, but you need to do a lot of programming work to adapt and input all the specific data and modifications that meet your organization specific need. That integration work is the complex and expansive part. It's the same for the IPMS.
 

The point is that the same technology is now available for both civilian and military platforms. And with respect to navigation, are your positioning and situational awareness needs (exempting aircraft) any greater than an offshore survey vessel, a cable layer, a trawler, or a semi-submersible rig?

Actually, they are greater: None of the civilian ship you mention have to do their work at 30 Kts, while swinging wildly to port or starboard at the rate a warship at speed can turn, while feeding this very precise information on movement to systems that need it to be able to basically shoot a bullet at another, incoming, bullet.

Finally, with respect to Navy Shooter's comments about the portability of the Halifax Modernization I believe that that has already be demonstrated by the selection of the same system for the New Zealand frigate upgrades.

http://www.lockheedmartin.ca/ca/what-we-do/naval-combat-management-systems.html

A different ship, with different sensors and weapons but the same combat management system provided by Lockheed.

Same combat management system, but because it has different weapons and sensors, a different integration. However, having just completed the integration work of their base system for the Halifax's, LockMart was able to be more precise and more reliable in quoting the price of integrating these into their base combat system.

I hope we are still friends, Chris  :cheers:
 
 
th Oldgate,for your explanation,even i got it.  :bowing:

Well to be fair not all the terms and abbreviations but hey i'm learning here(not an marine expert,just an enthusiast) [:p

Hope you 2 are still friends,lol :P

gr,walter
 
Oh I got it Walter.  I was just delaying the inevitable prior to admitting defeat.  Not that I am admitting defeat.....  ;D

I have to keep trying.

Point taken on the incorporation of the Gas Turbine.  (I would buy myself some wiggle room by pointing out that all the vessels in question were based on safe technologies of the 1990s and designed in response to the threat appreciation of the 1990s  -  As noted earlier in the thread technologies, threats and responses have all changed.  Perhaps the needs assessment of 2016 is different than that of 1996?)

http://marine.man.eu/docs/librariesprovider6/marine-broschures/diesel-electric-drives-guideline.pdf?sfvrsn=0
http://www.qe2.org.uk/engine.html
http://news.usni.org/2015/09/23/navy-set-to-install-hybrid-electric-drives-in-destroyer-fleet-staring-next-year
http://www.l-3mps.com/maritimesystems/hybrid-ehmti-042013.aspx

As far as "which industries" - I will admit that no industries use multiple power sources - except insofar as converting all power to electricity and then using electricity uniquely to power its rotating equipment and controls. Regardless of load or response times.
That electricity comes from on-site gensets and cogen plants, or offsite wind, hydro, nuclear, coal, gas, diesel..... The point is that the electrical system permits flexibility and is a lot less demanding in terms of space.

With respect to "pods" - perhaps I should reword that and say "nacelles", or even modules.  The notion is that the prop, motor and reduction gear can all be treated as a compact module, that is relatively easy to accommodate within the hull structure, conformally.  It doesn't have to be dangling in the breeze (or is that the wake?) and it doesn't have to azimuthing.  You can still employ a conventional prop and rudder control system. And the propulsor unit is discrete from the power supplies which can be distributed along the length of the keel as well as port and starboard making the ship less vulnerable to damage in any given sector.  One genset flooded and the ship can still "float-move-fight" (I believe was the expression?).

WRT hull forms - I think, OGBD, you may be underestimating how much fuel efficiency is valued in the civilian world.  And, in any event, if the civilian yards can create complex bow and stern forms then they can certainly manage to create more "interesting" module shapes when they are buggering about in between.

Civilian doesn't just mean Emma Maersk.  It incorporates a multitude of designed for purpose work boats.

WRT navs, platform management and combat systems management - I suspect a rapprochement is likely there - both technically and between ourselves.

Once the databus is defined than we are simply debating what sensors, switches and motors are being incorporated.

Final point:

I am a strong believer in working with what is available within the budget that is available. I know all things are possible if cash... but there is never enough cash.  That means trying to figure out how to get the most out of what I, and my clients, can afford. In this context, I suggest, that means trying to figure out how much you might be able to achieve by buying to civilian standards and incorporating civilian design concepts.

That is, after all how we ended up with the Corvettes - derived from the whale catcher Southern Pride.

Southern_Pride%2C_after_RN_conversion.jpg

https://upload.wikimedia.org/wikipedia/en/3/3d/Southern_Pride%2C_after_RN_conversion.jpg

What could be accomplished with this as a model?

doc_92_5.jpg


http://www.havfisk.no/en/fleet/fleet-overview/gadus-neptun
http://www.havfisk.no/upload_images/83660EB698B149C9A5A3CFF5E8501A80.pdf

http://www.havfisk.no/upload_images/83660EB698B149C9A5A3CFF5E8501A80.pdf

She is no high speed frigate, agreed, but neither is she simply a floating box with a pointy end.

Your service, Sir.  :cheers:

 
By the way:

Here is a link to a virtual tour of Gadus Neptun

http://invisual.no/havfisk/
 
Some more links on the use of electrical power

A discussion comparing Gas Turbine powered compressors to electric compressors and the use of permanent magnets.

http://www.nist.gov/pml/high_megawatt/upload/7_1_Weeber-Approved.pdf

Some applications for permanent magnets:

"This machinery is undoubtedly a new departure for fishing vessels towards electrical drive", explains Ramon Carreira, General Manager of Ibercisa, adding that to have this type of equipment allows improved operational performance on board the vessel - less power installed, better flexibility to overcharge electrical engines for temporary use by increasing par; lower installation costs, elimination of pipes and onboard oils, simplification of on board systems, improved noise levels, and more environmentally friendly, not forgetting considerable savings in fuel costs".

Apart from control systems the Ibercisa order is comprised of the following:

2 electric split trawl winches electrically driven by a 360 kW - 600 rpm - 440 V, controlled by frequency converter; with a capacity for 3000 m rope Ø 34 mm or 3.400 m Ø 32 mm with a pull of 49,5 tons at first lay at 37,8 m/min.

2 electric Gilson winches driven by 75 kW a 1800 rpm ; with capacity for 125 metres of Ø40 mm rope and pulling power of 22,2 tons at19 m/min on the first layer.

6 electric sweepline winches driven by 110 kW motor a6 1800 rpm with a capacity of 1.100 metres of Ø28 mm wire and a line pull of 14,3 tons at 30 m/min.

2 electric net sounder winches driven by electric motor of 55 kW at 1800 rpm; with capacity of 4.000 metres of Ø11,3 mm wire and with a capacity for 5,5 tons at a speed of 55m/min.

2 electric cod end winches driven by electrical motor 75kW at 1800 rpm with a capacity for 150 m wire of Ø22 mm and a line pull power of 12,9 tons at 32,4 m/min.

3 electric net drums: one driven by an electric motor of 260 kW a 1800 rpm with capacity of 20 m3 of net and a line pull power of 29,8 tons at 45 m/min; another with a motor of 30 kW and a motor of 30 kW at 1800 rpm with a capacity for 13 m3 of net and a pull of 5,5 tons at 28 m/min; and a third drum with dual control for a motor of doble accionado motor of 105kW at 1800 rpm with capacity for 14 m3 of net (2 x 7 m3).

1 electric auxiliary anchor winch driven by a 55 kW motor at 1000 rpm and capacity for 370 metres of 44mm wire and a pul of 21,2 tons at 12,4 m/min.

1 electric mooring winch driven by 18,5 Kw motor at 1800 rpm with capacity for 290 mm chain of 28mm and a pull of 9,3 tons at 11 m/min

2 electric auxiliary winches of 45 kW at 1800 rpm with a pull of 7,8 tons a t 31,8 m/min on the first layer.

2 electric auxiliary winches with 5 kW a 1800 rpm motor with automatic and electromagnetic brake with a capacity for 60 metres of Ø12 mm chain and a pull of 0,8 toneladas at 37 m/min on the first layer.

The advantages of electric drive on fishing equipment are without doubt one of the great technological advances in optimization of fishing operations. The installation of electrically driven machinery gives immediate benefits in terms of vessel exploitation costs by greatly affecting one of any boat owners biggest headaches: fuel costs.

Electrical controls on the machinery not only reduce the space needed for installation but are also lighter and more efficient, giving better winch performance with the automatic trawl system. However these are not the only reasons in favour of the electrical drive control. Others are:

- Installation costs are lower as no pipes or tubes are needed.
- Fuel consumption is lower, maintenance and noise levels are also reduced, improving the security and health of workers on board.
- The control systems of winches using alternative currents, are comprised of frequency variators, alternative current (AC). winch gearbox, refrigeration system for motors and an energy regeneration system.
- The greater efficiency of the winch (input/output power) and the possibility of regenerating power during cast off improve the fuel consumption ratios of the vessel.
- The control system efficiency of electric drive is situated around 85%-90% as opposed to the hydraulic drive which can vary between 50% and 70%.
- They offer better control than hydraulic systems, variable speed control from 0%-100% of maximum rpm and all the par at any rpm level.

http://www.industriaspesqueras.com/noticias/tecnologia/37833/ibercisa_will_suplly_deck_machinery_for_the_new_trawler_of_fishermen_finest_.html

Contra-Rotating propellers with electric drive.

http://www.scana.no/sites/all/files/Contra%20Rotating%20Propulsion_0.pdf

 
As far as Pods go, they seem best suited for slower vessels that need to be very maneuoverable. I recall reading somewhere that at high speeds they can have issues and that they are not the best for directional stability. 
 
On the issue of how quickly naval shipbuilding costs can balloon, this is not just a NATO/AUS issue, it appears to be a profiteering, capitalist democracy issue:

"Initially in 2008, the total program cost with long-term spare parts was expected to cost ₹ 3,800 Crore (US $950 Million),[30] but the construction costs escalated about 225% , and by 2011, cost of the program became ₹ 11,662 Crore (about US $2.6 Billion at that time), with each ship costing ₹ 3,900 Crore (about US $870 million at that time).[31] The Defense Minister A. K. Antony cited the causes being the delay in supply of warship-grade steel by Russia, increase in costs of Russian specialists due to inflation during the build period, wage revision due from October 2003 and delay in finalization of cost of weapons and sensors."

Kolkata Class Destroyer: https://en.wikipedia.org/wiki/Kolkata-class_destroyer
 
Colin P said:
As far as Pods go, they seem best suited for slower vessels that need to be very maneuoverable. I recall reading somewhere that at high speeds they can have issues and that they are not the best for directional stability.

I probably should have been more careful with the use of the word pod.  Perhaps propulsor module or somesuch would be more appropriate.

The pod is one example of a group of electric drives that essentially cause the propeller to become an electric mixer at the back of the boat.  It can hang underneath in its own pod, which can be uni-directional or azimuthing, or it can be conformally integrated into the hull.  The article below does a great job of describing the development from the first electric battleships in 1917 (the Tennessee class) to the Zumwalt via the diesel electric and nuclear submarines.

http://www.defensemedianetwork.com/stories/going-electric/

Some highlights

In each case, the ship’s prime mover drives a generator rather than a propeller shaft. The propeller (or propulsor) is driven by a motor wired to the generator. In modern cruise ships, this kind of arrangement makes it possible to place the propellers in pods, which can rotate to turn the ship – to give it unusual maneuverability for its size. In a warship, electric power in itself might have several consequences. One would be that the ship would not have to run all of her engines all the time, because electric power from any of them could drive all of her propellers. At the very least, that would make for much better efficiency and longer range at a given speed. That increased efficiency alone justified electric drive for several new major amphibious ships. USS Makin Island (LHD 8), first of the class to use a gas-turbine/electric drive, made news in 2009 for saving $2 million during her transit from Pascagoula, Miss., to San Diego, Calif. The Navy’s Lewis and Clark-class T-AKE dry cargo and ammunition ships also use an integrated propulsion system. The ships’ four MAN diesel generators serve two electric propulsion motors driving a single shaft. The first of class Lewis and Clark was launched in 2005.

In the 1980s, the Royal Navy adopted partial electric drive for its new Type 23 frigates because electric drive isolated the quiet propeller from the ships’ inherently noisy diesel engines used at low speed. Because the diesel did not have to be connected directly to the propeller, it could be sound-mounted. In the past, frigates, which had to be silenced, were generally powered by relatively inefficient, but inherently quiet, gas turbines. Diesels were far more efficient, but also produced far more noise, and silencing them (e.g., by sound-mounting and hooding) was expensive and elaborate, mainly because the ships’ propeller shafts still had to be connected directly to their engines. Modern diesel-electric submarines do not have this problem because their diesels drive generators, hence, are easier to sound-mount and hood. The argument favoring diesel efficiency may become important to the U.S. Navy in a future of expensive fuel. In the late 1980s, the Royal Navy generally espoused electric drive in future surface warships on economy grounds.

Because the engines did not have to be placed in line with the motors actually driving the propellers, they could be spread out in such a way that the ship could not be disabled by a single hit. For example, the power plant could be divided (at least in theory) between a portion in the conventional below-water position (where it was reasonably well protected against above-water attack) and a portion above water, hence better protected against underwater attack. Such dispersion did entail a larger ship and some problems of routing uptakes and downtakes, and it has not yet been attempted – but it is probably in the cards if navies become more interested in survivability. Electric power could be routed to the motors along several paths, further improving the ship’s ability to survive damage. This seems to have been done in the new Zumwalt. Quite aside from that, eliminating a long propeller shaft would eliminate an important vulnerability, in that the shaft itself could be distorted by underwater damage (such as shock). If it kept turning, it would tear up the ship’s bottom. If that seems a remote consideration, remember that a bent shaft that kept turning helped considerably to sink the British battleship Prince of Wales in 1941 by opening up the ship’s hull like a sardine can.

The technology is being used for work boats

http://www.nortrade.com/sectors/news/stadt-electric-propulsion-to-8-offshore-vessels

and for cruise liners.

http://www.hightechfinland.com/direct.aspx?area=htf&prm1=889&prm2=article


Concurrently there is movement from induction motors to permanent magnet motors which permit the elimination of the weight and volume of a mechanical gearbox entirely.  And it also permits the development of novel solutions like contra-rotating propellers without mechanical gear boxes or planetary gears etc.

http://www.inpower.no/news/permanent-magnet-technology-from-inpower-to-scana-propulsion

magnet.jpg


Finally, on the power supply front, a couple of alternatives to the gas turbine - multiple diesels

http://www.wartsila.com/energy/learning-center/technical-comparisons/combustion-engine-vs-gas-turbine-advantages-of-modularity

and batteries

https://www.utexas.edu/research/cem/Energy_storage_photos/Energy%20Storage%20on%20Future%20Electric%20Ships.pdf

I understand that one of the advantages of the gas turbine is acceleration of the ship - but how long does it take to get up to speed from a cold start?  Or alternatively, how much fuel do you burn idling?
 
I know on are old RR Gnome turbine, the difference between "idle" and top speed was from 60-80 gallons roughly as I recall. Basically the turbine runs within a set RPM band regardless of load, we could be off the ramp from cold in 3 minutes when the alarm rang. I don't know how that translate to a big turbine. 
 
Colin P said:
I know on are old RR Gnome turbine, the difference between "idle" and top speed was from 60-80 gallons roughly as I recall. Basically the turbine runs within a set RPM band regardless of load, we could be off the ramp from cold in 3 minutes when the alarm rang. I don't know how that translate to a big turbine. 

From my time on IROQUOIS, the turbine fuel consumption was:

Pratt & Whitney FT4A Main engine
25L/min - idle
150L/min - full power (trimmed well.. they be as much as 180L/min) - 25,000 SHP
(about 15% more than the FFH's LM2500)

Cruise Engine Allison 570-KF
5L/min - idle
25L/min - full power (7500 SHP approx)
(.... a boat load more than the FFH PDE)

Due the superb fuel economy of the platform (pun intended), a common configuration if we didn't need to get anywhere quick was to drag a shaft and turn the other with a cruise engine online.
 
Thanks donaldk.

More numbers for me to play with and maybe increase my understanding.

Cheers.
 
All right, I think that the dust has settled a bit now, so time for my next intervention.

First of all, I think you hit he communication problem on the nose, Chris.

Yes, it was the suggestion of using "pods" that caused us to take issue, not the use of electric motors. In fact, as I pointed out, when paired with a standard shaft and screw combination, it is becoming more widely used by advanced navies (be it The Type 45, the Queen Elizabeth class or the Zumwalt) and it is generally designated as Integrated Electric Propulsion. This is not to be confused with the Type 23 (Duke class) or the mods to the Arleigh Burke's, which results in what is usually designated as CODLAG. In those last two types, the electric motors are connected to the complex gearing system so they can become a third option for propulsion.

For instance, the Burke's have, on top of their cruise/sprint main engines, three gas turbines generators. These gas turbines are smaller and consume less than the main ones. Two of these are required when all the electronics, hotel loads and weapons systems are running - the last one being the emergency back-up. Now, when just traveling from point A to point B (crossing the Atlantic coming back home, for example), the two running GT generators have excess electrical capacity from the ship's needs. Running them up to full, and if need be throwing the third in, costs a lot less fuel than running the mains but yet generate enough electricity to accommodate an electrical motor connected into the main gearing system to propel the ship economically.

Now, in the case of the next major surface warship of the Canadian navy, the propulsion plant has not been selected, that I know of, so using an Integrated Electrical Propulsion system is still possible. However, while more economical on fuel, such propulsion, especially on high speed warships is not necessarily cheaper to install onboard than a more conventional form of propulsion system. And the higher end need for power still requires gas turbines to provide the vast amounts of electricity required*. Also, electrical propulsion requires a lot of room for various supporting electrical components (transformers/rectifiers/frequency modifiers, heat dispensation systems, extra switchboards etc.).

BTW, the Canadian navy already is an "electric-propulsion" Navy. Other than the HAL and the last IRO, all the other commissioned ships and submarines are driven by electrical motors, and the AOPS will also have electrical motors for propulsion.

Finally, I am not sure I understand your point concerning the Gadus Neptun (though I like the single cabin for all living quarters). Since this is the Shipbuilding Strategy thread, are you suggesting our strategy should be to build a whole fleet of shrimp trawlers and empty the Grand Banks of yet another species of ocean animal?

If your point is to build "cheap" hulls as cost saving measure, then we are not getting through, I think. The ship's hull and machinery on modern warship, even though more complex and expensive than civilian ones, is not the largest part of the cost. What would you do with your "Gadus Neptun" derivative? Replace the trawl deck equipment with a Mk41 launcher of 32 slots? Then put what, 32 "quad" ESSM in 8 of them and use the others for 24 SM2 Block IIIB's? Just the missiles (not the launchers, not the electronic control launch systems and none of the required radars and fire directors or combat system to both detect and track the target on the one hand, and fire at them) will set you back  $108 million US - today. The things in the parenthesis, even without being fully integrated systems, will set you back another 60 to 80 millions US$. And we have not even touched on surface warfare or ASW. Who cares then if the hull/machinery costs you 100 or 200 millions?

But here is the other thing. In peace time, you don't plan on and build low end, second (or third) class ships that might be called for by a last minute emergency programs. You plan and build the higher end, complete capability warships that are the real fighters. And the corvette were stop gap until the real ships needed for escort - the larger proper frigates, destroyer escorts and destroyers, could be built in sufficient number by mid 1943, and new non-civilian technology came on line (centimetric radar, hedgehog and twin beam asdics that let you get bearing, distance and depth). And the corvettes were more of a make the merchant seaman feel good ship than anything. The only useful ship in the early escorts were the lone destroyers, and for safety, the admiralty relied on routing and lack of number of subs available to the enemy. 




* I note that you referred in one of your posts to the QE2 (the cruise ship). To show you the difference, we can compare her to the actual QE aircraft carrier. They both are electric driven, and both have electrical motors that require approximately 80 MW to feed at their higher speed. The QE2 does that with seven large diesel engines (she then has two "spares"). the motors and diesel engines basically occupy the same space that was previously devoted to the four steam turbines (two were reversing turbines) and three h-u-g-e (to quote the Donald) boilers. The two GT generators - same amount of power - on the QE, on the other hand are each located at the base of the two deck islands. If they used that on the QE2, they would have been able to fit the motors and the two GT generators in the old steam turbines engine room and gained the space of the three boiler rooms. There are other reasons (weight distribution and ship stability for instance) that dictated using nine large diesels ofr the QE2, but on a warship, any space we can save on machinery can be re-used for living quarters, stores and, most important - weapons and ammunition.   
 
WRT to Electric Boats:

When building Electric Boats do not give the contract to Lucas.

Delays on Trident replacement and Type 45 power failures probed by Defence Select Committee
Ministers on Defence Select Committee investigate huge defence projects which could have major implications on Britain's arms industry


By Alan Tovey, Industry Editor7:41PM GMT 03 Feb 2016

Two of Britain’s biggest defence projects in decades are being investigated by the Defence Select Committee in a probe that could have serious implications for the UK's arms suppliers.

MPs on the committee have written to Defence Secretary Michael Fallon questioning a lack of progress on a replacement for Britain’s Trident nuclear submarines. They also want to know exactly who is responsible for the repeated power failures on the Navy’s Type 45 destroyers.

....


The committee is also seeking clarity on the embarrassing power failures that have hit the Navy’s latest ships, the Type 45 destroyers, which entered service just seven years ago.

Last week the MoD confirmed six of the vessels will need major refits that are expected to run up a repair bill of tens of millions of pounds because the £1bn warships keep breaking down.

Type 45 destroyers – which were built by BAE – run off electricity produced by Rolls-Royce gas turbines and generators through an electrical grid supplied by General Electric, powering everything from the propellers to the radar.

However, running all the systems together causes the system to trip out, putting the vessel into a blackout and leaving it defenceless.

The select committee wants to know the details of the problems, including when they started and how often they have occurred, whether the cause is a failure of components, design or construction and who will pay to eliminate the problems.

In a letter to the Defence Secretary, Mr Lewis said: “The reports of engine failures and the refit programme appear to reflect a far more serious problem that ‘equipment reliability issues’ as described last year by MoD ministers.”

http://www.telegraph.co.uk/finance/newsbysector/industry/defence/12139146/Delays-on-Trident-replacement-and-Type-45-power-failures-probed-by-Defence-Select-Committee.html
 
"...six of the vessels..." "... six of the vessels..."  ? ? ? ? ? ? ?

There are only six vessels in the class. Perhaps they should have said " ... the six vessels ..." or "... all six vessels ...".

Just saying.  [:-[
 
Oldgateboatdriver said:
"...six of the vessels..." "... six of the vessels..."  ? ? ? ? ? ? ?

There are only six vessels in the class. Perhaps they should have said " ... the six vessels ..." or "... all six vessels ...".

Just saying.  [:-[

I think the expression you are looking for is: "The whole feckin lot of them!"
 
Chris Pook said:
WRT to Electric Boats:

When building Electric Boats do not give the contract to Lucas.

http://www.telegraph.co.uk/finance/newsbysector/industry/defence/12139146/Delays-on-Trident-replacement-and-Type-45-power-failures-probed-by-Defence-Select-Committee.html

be afraid, be very, very afraid http://www.lucasaerospace.eu/

Lucas switch have 3 positions, dim, flicker and smoke
 
Colin P said:
Lucas switch have 3 positions, dim, flicker and smoke
My first bike was a Norton. Oh, how I wish the Prince of Darkness had provided the third option of "dim."    ;)
 
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