Canadian Surface Combatant RFQ

[Underway]

Stop. You had me at "stateroom".

Although I agree, they need a more redundant propulsion system.

Also, why is it that 30,000 ton battleships went 30+ knots in 1942 but no one is making anything that goes more than 27 knots these days?

Short answer:  - design tradeoffs (higher speeds at higher seastates in current ships, better seakeeping, better maneuverability at higher speeds)
- the longer a ship is the higher its theoretical top speed.  Therefore bigger ships can go faster then smaller ships at the top end (in a displacement hull form).  Hence why US Carriers can outrun their escorts.  Higher top speed and the power to get there.

 

[Uzlu]

Scale model of Alion design proposal for Canadian Surface Combatant at CANSEC 2018. 

https://www.navyrecognition.com/index.php/news/defence-news/2018/june-2018-navy-naval-defense-news/6264-ge-pitching-lm2500-gas-turbine-for-canada-s-surface-combatant-program.html

 

[Oldgateboatdriver]

Short answer:  - design tradeoffs (higher speeds at higher seastates in current ships, better seakeeping, better maneuverability at higher speeds)
- the longer a ship is the higher its theoretical top speed.  Therefore bigger ships can go faster then smaller ships at the top end (in a displacement hull form).  Hence why US Carriers can outrun their escorts.  Higher top speed and the power to get there.

I believe that to be incorrect, Underway.

The length of a ship has no bearing on top speed for displacement hull. What does is the beam-to-length ratio. The smaller the ratio (where 1 to 10 is a smaller ration than 1 to 5, for instance), the faster a ship will be for a given power level, so long as you have an equally efficient hull form (obviously a small ratio with a blunt, square bow won't help you go fast).

But that is for a given amount of propulsion force, and for vessels of similar weight. All of these play in the picture.

Compare the old steamers with the IROs for instance: The Sallyrands achieved 28 Kts with a 1 to 8.7 ratio and 30,000 HP to push them along (I'll use shaft HP for all my examples). At 60 feet longer, by your logic, the IROs should have been faster. In fact they were marginally so with an extra 1.5 Kts. But they did so with an equivalent ratio of 1 to 8.5, but required an extra 20,000 HP to do so (50,000 HP).

The Arleigh Burke's can actually keep up with the US carriers, BTW, with top speeds above 32 Kts. That would seem to follow your logic, since they are 85 feet longer than the IROs. However, they need twice the power of the IROs to achieve it, at 105,000 HP. They have a beam-to-length ration of 1.78.

This last ratio is actually the same as that of a US carrier. But a US carrier needs 260,000 HP to achieve that speed. That amount of power (which, incidentally, only  a steam turbine can give you, sorry GT's  ) is the only thing that give these warships their speed.

A useful comparison is a US carrier with an Maersk company EEE class: The Emma Maersk has a ratio of 1 to 7. A little greater than a carrier, but  of comparable overall size with a Nimitz class. The E.M. achieves 25 Kts on 110,000 HP. You can see that the Nimitz class needs 150,000 extra HP just to achieve the last 7 Kts of her speed. This means that the Nimitz needs its last 60% of power to achieve her last 23% of speed.

This is normal, as speed increases, the amount of power required to go faster through the water grows exponentially. A good example is our own MCDV's: they can achieve 14 Kts with the first three DG's running, but running the fourth DG (for a 25% increase of power) only gives you an extra 1.5 Kts.

Scale model of Alion design proposal for Canadian Surface Combatant at CANSEC 2018. 

https://www.navyrecognition.com/index.php/news/defence-news/2018/june-2018-navy-naval-defense-news/6264-ge-pitching-lm2500-gas-turbine-for-canada-s-surface-combatant-program.html

Nice touch: Combining the frigates "300" series number with the old IRO's "80" numbering.  ;D

However, please tell me they shot the designer. Why on earth would we, in Canada, with what we know about ASW and how rough our waters can be, want to have a godda@n bow mounted sonar.  :facepalm:

 

[Oldgateboatdriver]

A small thought just occurred to me while looking again at that Alion proposed design at CANSEC 2018: Don't they know we stopped using green for our flight decks colour a long while ago.  ???  Good research, guys! ;D

 

[SeaKingTacco]

A small thought just occurred to me while looking again at that Alion proposed design at CANSEC 2018: Don't they know we stopped using green for our flight decks colour a long while ago.  ???  Good research, guys! ;D

Good story there. About a decade ago, the Navy phoned 12 Wing and asked: why are the flight decks green? They could not source that particular colour paint anymore and wanted to know what to do about it.

We started looking through old publications. Nothing.

We started phoning retired naval air folks. Nobody could remember why.

After a month or so, we were forced to admit that, as far as we could determine, HMCS Bonaventure was delivered with that colour flight deck. Since then, it was just assumed by everyone that that was the colour one used for flight deck (even though, no one else but Canada did it that way).

We came to the conclusion that switching to grey would not be the end of the world and the Brits played a massive, half century long joke on us.

 

[FSTO]

Good story there. About a decade ago, the Navy phoned 12 Wing and asked: why are the flight decks green? They could not source that particular colour paint anymore and wanted to know what to do about it.

We started looking through old publications. Nothing.

We started phoning retired naval air folks. Nobody could remember why.

After a month or so, we were forced to admit that, as far as we could determine, HMCS Bonaventure was delivered with that colour flight deck. Since then, it was just assumed by everyone that that was the colour one used for flight deck (even though, no one else but Canada did it that way).

We came to the conclusion that switching to grey would not be the end of the world and the Brits played a massive, half century long joke on us.

:rofl: :rofl: :rofl: :rofl: :facepalm: :rofl: :rofl: :rofl: :rofl: :rofl:

Young sub walks up to grizzled Chief and says "Why do.....?
Chief holds up hand and says "Cause its always been that way sub; you may carry on sir!"

 

[Kirkhill]

Probably not the most valid reference but.....

If I remember correctly, having built a fair number of AirFix plastic models of British Carriers as a kid,  all the RNs WW2 carriers had green decks with yellow markings.  So it is likely that you got HMS Powerful (HMCS Bonaventure) from Harland and Wolff just the way the RN specified her.

Here's Centaur and you can see a clear colour difference between the hull and the flight deck.

 

[Underway]

I believe that to be incorrect, Underway.

The length of a ship has no bearing on top speed for displacement hull. What does is the beam-to-length ratio. The smaller the ratio (where 1 to 10 is a smaller ration than 1 to 5, for instance), the faster a ship will be for a given power level, so long as you have an equally efficient hull form (obviously a small ratio with a blunt, square bow won't help you go fast).

But that is for a given amount of propulsion force, and for vessels of similar weight. All of these play in the picture.

Compare the old steamers with the IROs for instance: The Sallyrands achieved 28 Kts with a 1 to 8.7 ratio and 30,000 HP to push them along (I'll use shaft HP for all my examples). At 60 feet longer, by your logic, the IROs should have been faster. In fact they were marginally so with an extra 1.5 Kts. But they did so with an equivalent ratio of 1 to 8.5, but required an extra 20,000 HP to do so (50,000 HP).

The Arleigh Burke's can actually keep up with the US carriers, BTW, with top speeds above 32 Kts. That would seem to follow your logic, since they are 85 feet longer than the IROs. However, they need twice the power of the IROs to achieve it, at 105,000 HP. They have a beam-to-length ration of 1.78.

This last ratio is actually the same as that of a US carrier. But a US carrier needs 260,000 HP to achieve that speed. That amount of power (which, incidentally, only  a steam turbine can give you, sorry GT's  ) is the only thing that give these warships their speed.

A useful comparison is a US carrier with an Maersk company EEE class: The Emma Maersk has a ratio of 1 to 7. A little greater than a carrier, but  of comparable overall size with a Nimitz class. The E.M. achieves 25 Kts on 110,000 HP. You can see that the Nimitz class needs 150,000 extra HP just to achieve the last 7 Kts of her speed. This means that the Nimitz needs its last 60% of power to achieve her last 23% of speed.

This is normal, as speed increases, the amount of power required to go faster through the water grows exponentially. A good example is our own MCDV's: they can achieve 14 Kts with the first three DG's running, but running the fourth DG (for a 25% increase of power) only gives you an extra 1.5 Kts.

In my defence I did say short answer to not get into a massive power curve, bow design engineering discussion.  But yes the hull length is more critical to a ships speed than most people realize.  Design hull speed is calculated by the equation 1.34*sqrt(length of hull at waterline in feet).  It's fairly accurate for displacement ships.  Bunch of theory goes into this but essentially it's where the power curve of cost vs pushing through the bow wake is impossible as the power required to push through is exponentially vertical. Now of course more power will allow you to actually reach this hull speed (cost vs benifit tradeoff), and most ships don't have enough power to do this without planing or going semi-displacement. And of course bow design is important in this as well as it can significantly help with the power curve.

A good short article here for how naval ships can be designed to reach their maximum hull speeds.
Ref:  http://large.stanford.edu/courses/2007/ph210/shank2/

As for US Carriers, they can, when going their max design hull speed outrun their escorts.  They won't out accelerate them but their max speed is higher. 

:2c:

Nice touch: Combining the frigates "300" series number with the old IRO's "80" numbering.  ;D

However, please tell me they shot the designer. Why on earth would we, in Canada, with what we know about ASW and how rough our waters can be, want to have a godda@n bow mounted sonar.  :facepalm:

Towed arrays of various sorts are really quite good and don't come out of the water in heavy seas.  :nod:

 

[jollyjacktar]

I remember talking with a retired sailor who sailed on the carrier USS Eisenhower.  He said they had her up to 55 knots in trials.

 

[Uzlu]

I remember talking with a retired sailor who sailed on the carrier USS Eisenhower.  He said they had her up to 55 knots in trials.

According to http://www.navweaps.com/index_tech/tech-028.php, the US Navy publicly released the speeds for three Nimitz-class aircraft carriers.

Nimitz: 31.5 knots
Theodore Roosevelt: 31.3 knots
Harry S. Truman: 30.9 knots.

 

[MarkOttawa]

jollyjacktar: Perhaps talking in KPH? .

Mark
Ottawa

 

[Oldgateboatdriver]

Or just pulling his leg. 

 

[Colin Parkinson]

Maybe wind over the deck 

 

[Baz]

As for US Carriers, they can, when going their max design hull speed outrun their escorts.  They won't out accelerate them but their max speed is higher. 

When I was at the Bi-National Planning Group in CSprings the US Co-Director was Capt Kendall Card; his last posting was CO of USS Abraham Lincoln during the Tsunami relief (and also the George Bush "Mission Accomplished" fly on, but that's another story).

He gave us a briefing on the Tsunami operations, which was interesting not the least from the fact his background was a 60 pilot, and he actually flew some of the missions.  One of the items I remember from the brief was that in order to get on-sta as quickly as feasible they outpaced their escorts, which is a relatively big deal in that area of the world.  They also disembarked most of (the entire?) fixed wing complement so they could concentrate on helos.

It was interesting to hear the capabilities that a Carrier with a helo heavy complement and a large flat deck amphib brought to the op... even some of the stuff about how they used small decks to support helo ops was obvious when they said it, but maybe not so much so if he you had to think of it yourself.

 

[jollyjacktar]

Or just pulling his leg. 

Possibly, possibly.  Buggered if l know how fast she was with all boilers lit and the pedal to the metal ( in ideal conditions)

jollyjacktar: Perhaps talking in KPH? .

Mark
Ottawa

:dunno:  maybe that was downhill, in neutral. 

 

[MarkOttawa]

Any influence on CSC decision? Build-in-Oz cost seems roughly comparable to build-in-Canada. Note AEGIS radar at end with missile defence capability:

Australia tipped to buy British naval frigates in $35 billion deal with old partner

Britain is strongly tipped to win the hard-fought contest to design and build Australia’s new $35 billion fleet of naval frigates in a move that would firm up the partnership with a key ally at a time of international political uncertainty.

Sources in Canberra and defence industry circles said it was all but certain that Britain’s BAE Systems would be chosen as the international partner to design and help build what will form the backbone of the Royal
Australian Navy’s surface fleet for the coming decades.

The national security committee of cabinet is expected to discuss the decision soon, with an announcement possible by the end of next week.

The British firm has been in a race against Italy’s Fincantieri and Spain’s Navantia for the contract to provide a design and help Australia build nine new frigates, starting in 2020 [emphasis added, significantly earlier than CSCs, eh?]. BAE has previously said the project will create more than 5000 jobs.

Defence has assessed the three bids and is understood to have made a recommendation on which offering would give the navy the best capability for key missions such as hunting enemy submarines...

BAE’s Global Combat Ship is regarded as the most modern design and the best suited to anti-submarine warfare. However because it remains a design on paper and has not yet been built, it also potentially poses a greater risk of delays and blowouts [emphasis added].

BAE has argued that since it is building the first few ships for the British navy, any problems will be ironed out there.

The construction will take place in Adelaide. Defence Industry Minister Christopher Pyne has spruiked the project as central to creating a long-term naval shipbuilding industry in Australia.

They will be equipped with a US-made Aegis combat system meshed with locally made SAAB Australia technology to integrate Aegis with the radar system. That will give it strong capabilities to target planes and even missiles.
https://www.smh.com.au/politics/federal/australia-tipped-to-buy-british-naval-frigates-in-35-billion-deal-with-old-partner-20180619-p4zmea.html

Mark
Ottawa

 

[Underway]

Any influence on CSC decision? Build-in-Oz cost seems roughly comparable to build-in-Canada. Note AEGIS radar at end with missile defence capability:

Mark
Ottawa

Aegis isn't a radar, it's a combat management system, which doesn't give it strong capability to defend against missiles any more than any other combat management system out there.  It's the sensors and the weapons that give it missile defence capability combined with the CMS.  They are a team.

The Oz radars will not be the SPY-1 system on the frigates as they SPY-1 is already on the Hobart Class.

 

[RDBZ]

SPY-1 is now a legacy system, with the US Navy moving to SPY-6 on flight 3 ABs and the RAN to the CEAFAR + CEAFAR2-L combination.

 

[oskarm]

Hello,

I have digged last year posts in this topic, but I have not find any technical requirements for SSC. Were there published any unclassified requirements?

In topic of moving helicopters on the deck, US on LCS and NZ on Canterbury uses electrical tugs like this: https://www.mototok.com/blog/the-perfect-helicopter-tug
Does any one know how it works in practice at higher sea states? Is it suitable for North Atlantic for a frigate?

---------------------------------------------------------------------------------------------------------------------------
Some clarification of misunderstandings that i have red in this topic.

1) AEGIS with SPY-1 and SPG-62 can engage much more targets simultaneously then 3-6. It would be true if SM-2 and ESSM could use only Home All the Way metod of targeting. But this missiles can use 1-way or 2-way up-linking (depending on radar system and version of the missiles). Up-linking is done by SPY-1. Ilumination from SPG-62 is needed only for 3-4 seconds before missile hit its target. Real number of targets is cassified, but estimations are 18-32 (probably it depends on version of AEGIS ane SPY-1).

2) Today medium or high speed diesels can accelerate as rapidly as turbines. Eg. Iver Huitfeld can go from idille to full torque within 15 seconds (both engines and variable pitch propellers). I dont know how healthy it is for durability but other engins monofacturers clame the same.
In my oppinion reason that OMT did not placed its offer could be:
- noisy CODAD that makes passive sonar useless for subs detecting (Ultra Electronic's towed sonar should be one of the best in passive detection in the world).
- other requirments like higher shock resistant and lots of other minior requirments that would drive to virtualy new design. If Canada can afford pay 2-2,5 more per ship and the real problem is crewing the ships, then why not.

 

[Uzlu]

other requirments like higher shock resistant and lots of other minior requirments that would drive to virtualy new design.

The Royal Canadian Navy appears to be asking for the moon.  I would not be surprised if the final design chosen is a lot closer to a clean-sheet-of-paper design than a slightly modified off-the-shelf design.