Dutch ships and designs and the possibilities for Canada

[Colin Parkinson]

I call BS on their claims of year round ice performance, likley a ice strengthened hull and modifications to machinery to operate in arctic cold weather.

OSK Design unveils latest concept for an Arctic frigate - modern engineering designed for extreme Northern operations

Leaders in maritime innovation, OSK Design, introduces their latest design, the Arctic frigate, an exceptional vessel meticulously crafted for operations in the North Atlantic, High North, and Greenland regions. This multi-purpose Arctic frigate is ...

www.vesselfinder.com

 

[Rainbow1910]

I call BS on their claims of year round ice performance, likley a ice strengthened hull and modifications to machinery to operate in arctic cold weather.

OSK Design unveils latest concept for an Arctic frigate - modern engineering designed for extreme Northern operations

Leaders in maritime innovation, OSK Design, introduces their latest design, the Arctic frigate, an exceptional vessel meticulously crafted for operations in the North Atlantic, High North, and Greenland regions. This multi-purpose Arctic frigate is ...

www.vesselfinder.com

Danish firm OSK Design introduces Arctic frigate design for Northern O

According to a PR published by OSK Design on September 12, 2023, the firm has revealed its Arctic frigate concept tailored for operations in the challengin

navyrecognition.com

It is being proposed to the Danish Navy as a replacement for their Thetis-class patrol vessels at this point. The video above shows a spokesman saying that this design is planned to be Polar Class 5.

 

[Colin Parkinson]

Danish firm OSK Design introduces Arctic frigate design for Northern O

According to a PR published by OSK Design on September 12, 2023, the firm has revealed its Arctic frigate concept tailored for operations in the challengin

navyrecognition.com

It is being proposed to the Danish Navy as a replacement for their Thetis-class patrol vessels at this point. The video above shows a spokesman saying that this design is planned to be Polar Class 5.

Polar 5 is basically AOP's level. How they hope to do that and make 23 kts is beyond me. There is no freebies in ship designs, so I am unclear how they plan on squaring the circle.

 

[Rainbow1910]

Polar 5 is basically AOP's level. How they hope to do that and make 23 kts is beyond me. There is no freebies in ship designs, so I am unclear how they plan on squaring the circle.

I've seen a tonnage figure for this thrown around at roughly 6,000t, the dimensions are roughly similar to a Halifax class frigate or other smiliar smaller/mid-sized frigates. You can get higher speeds however, that requires a hull form which is less suited to icebreaking and more suited to speed/open ocean performance. AOPS had issues reaching its initially set design top speed of 20 knots as it those few extra knots would require immensely more speed, so it was lowered to 17 knots (something AOPS has apparently more than exceeded in service). This ship is very likely going to have a far smaller mechanical and manpower endurance compared to AOPS, it's potential to break ice will likely be inferior even if similarly classed as well. It's crew compliment is also going to be far higher due to the additional weaponry and equipment. As you say, something has to give here and at this point, it is difficult to assess exactly what that might be.

This company can say all they want at this point in the design but currently the design exists only on paper, so claims should be taken with a grain of salt.

 

[Underway]

Polar 5 is basically AOP's level. How they hope to do that and make 23 kts is beyond me. There is no freebies in ship designs, so I am unclear how they plan on squaring the circle.

PC 4	Year-round operation in thick first-year ice, which may include old ice inclusions	Over 120 cm (3.9 ft)
PC 5	Year-round operation in medium first-year ice, which may include old ice inclusions	70 to 120 cm (2.3 to 3.9 ft)

AOPS is PC 4 by this table provided in Wikipedia (based on public domain released performance). I assume the Dutch and Canada are using the same PC as there are few different ones out there.

I agree that 23 knots is going to be hard. I think they could do it if they dropped the requirement for ice operations to the 70cm thickness level. AOPS does 18+ (again open sources) so reducing weight could perhaps get you to 23kts (5 more above AOPS).

 

[Colin Parkinson]

PC 4	Year-round operation in thick first-year ice, which may include old ice inclusions	Over 120 cm (3.9 ft)
PC 5	Year-round operation in medium first-year ice, which may include old ice inclusions	70 to 120 cm (2.3 to 3.9 ft)

AOPS is PC 4 by this table provided in Wikipedia (based on public domain released performance). I assume the Dutch and Canada are using the same PC as there are few different ones out there.

I agree that 23 knots is going to be hard. I think they could do it if they dropped the requirement for ice operations to the 70cm thickness level. AOPS does 18+ (again open sources) so reducing weight could perhaps get you to 23kts (5 more above AOPS).

My understanding is that AOP's is PC 5 hull and PC 4 bow?

 

[Kirkhill]

My understanding is that AOP's is PC 5 hull and PC 4 bow?

Here's a question from the silly seats:

Does the speed of the vessel have an impact (sorry) on the Ice Class calculation?

6000 tonnes hitting an ice wall at 23 knots is going to generate a lot more punch than 6000 tonnes at 18 knots.

 

[Colin Parkinson]

Here's a question from the silly seats:

Does the speed of the vessel have an impact (sorry) on the Ice Class calculation?

6000 tonnes hitting an ice wall at 23 knots is going to generate a lot more punch than 6000 tonnes at 18 knots.

That "punch" goes both ways, icebreakers wear out from thrashing through the ice. Also your propulsion units that are optimised for speed, while likley be vulnerable to ice. Ice took off a blade of the Polar Star, a US heavy icebreaker. PC 5 is all first year ice and things can go badly if you hit multi-year ice. The CCG almost lost the Camsell icebreaker from hitting a growler, which tore a hole in her hull.

 

[Kirkhill]

That "punch" goes both ways, icebreakers wear out from thrashing through the ice. Also your propulsion units that are optimised for speed, while likley be vulnerable to ice. Ice took off a blade of the Polar Star, a US heavy icebreaker. PC 5 is all first year ice and things can go badly if you hit multi-year ice. The CCG almost lost the Camsell icebreaker from hitting a growler, which tore a hole in her hull.

Seen.

Funny you should mention about props. Has there been any news about the Svalbard sustaining any damage to its running gear? She has those rotating, reversible azipods. As I recall one way that they were to be used was as grinders. The ship was supposed to turn the props aft and drive the ship into the ice stern first so that the first part of the ship to contact the ice was the props. The claim was that it could grind through a few multi-year ice a few meters thick for a short distance.

ABB Azipod® propulsion: conquering ice

Where winters are harshest, the toughest technology is required for marine operations to continue uninterrupted during the frozen months. For 30 years, Azipod® propulsion has proven to be up to the task, keeping harbors open and moving goods and ...

www.vesselfinder.com

By the way. The Arctic Frigate design under discussion is a Danish design, not a Dutch one. The Danes have been operating Thetis (3500 tons) and Knud Rasmussen (1700 tons) class OPVs in the proposed area of operations for a number of decades.

 

[Colin Parkinson]

Seen.

Funny you should mention about props. Has there been any news about the Svalbard sustaining any damage to its running gear? She has those rotating, reversible azipods. As I recall one way that they were to be used was as grinders. The ship was supposed to turn the props aft and drive the ship into the ice stern first so that the first part of the ship to contact the ice was the props. The claim was that it could grind through a few multi-year ice a few meters thick for a short distance.

View attachment 80175

ABB Azipod® propulsion: conquering ice

Where winters are harshest, the toughest technology is required for marine operations to continue uninterrupted during the frozen months. For 30 years, Azipod® propulsion has proven to be up to the task, keeping harbors open and moving goods and ...

www.vesselfinder.com

By the way. The Arctic Frigate design under discussion is a Danish design, not a Dutch one. The Danes have been operating Thetis (3500 tons) and Knud Rasmussen (1700 tons) class OPVs in the proposed area of operations for a number of decades.

Thetis = 21kts top speed, PC 6 (borderline PC 7)
Knud Rasmussen + 17kts. PC 6

I don't know enough about azipods and how efficient they are when your getting up to higher speeds?

 

[Kirkhill]

Thetis = 21kts top speed, PC 6 (borderline PC 7)
Knud Rasmussen + 17kts. PC 6

I don't know enough about azipods and how efficient they are when your getting up to higher speeds?

Me neither.

 

[SeaKingTacco]

Here's a question from the silly seats:

Does the speed of the vessel have an impact (sorry) on the Ice Class calculation?

6000 tonnes hitting an ice wall at 23 knots is going to generate a lot more punch than 6000 tonnes at 18 knots.

6000 tonnes of ship hitting an ice wall at 23 knots will do terrible damage to the crew….

 

[Oldgateboatdriver]

Denmark uses the RRS rules. What they call "polar" is actually "Arctic", so the Polar 5 level they describe is equivalent to our PC 6. That is summer navigation (notice they don't say icebreaking, but navigation) in the Arctic i.e. mostly open water or going through some patches of growlers made of first year ice. That is all they need since their Arctic waters, around the Faroes and the southern edges of Greenland are mostly ice free in summer.

 

[Underway]

My understanding is that AOP's is PC 5 hull and PC 4 bow?

Essentially. The parts of the ship that will be exposed to higher ice pressures/forces have been reinforced. I think its the more modern computer modeling way that ships are being built (and cars/aircraft/buildings etc...). You design the object, subject it to forces in a simulation and then look at its deformation. In that way you can build a ship that is essentially PC 4 without having to reinforce areas that won't be subject to forces, thus potentially saving material, reducing build times, cutting weight and increasing fuel efficiency.

Or they just said, "The stupid NWO's will ram this into stuff they shouldn't, we should just add some extra strength here because they'll wreck the ship otherwise".

 

[Colin Parkinson]

Denmark uses the RRS rules. What they call "polar" is actually "Arctic", so the Polar 5 level they describe is equivalent to our PC 6. That is summer navigation (notice they don't say icebreaking, but navigation) in the Arctic i.e. mostly open water or going through some patches of growlers made of first year ice. That is all they need since their Arctic waters, around the Faroes and the southern edges of Greenland are mostly ice free in summer.

Ice classes can give you a headache. There was a nice graphic that lined them all up on the web, but can't find it anymore.

 

[dapaterson]

Or they just said, "The stupid NWO's will ram this into stuff they shouldn't, we should just add some extra strength here because they'll wreck the ship otherwise".

This.