UK Defence Forum

This mantra of a shallow draft first appeared in a blog post by sir Humphrey written simple to just the fact a opv had been sent to these places and to divert criticism.

Were as the real reason they were built and sent has nothing to do with draft and everything to do with over complication and dithering thru countless studies of a type 23 replacement from a navy command that was more interested in a me too U.S. navy power projection on land construct than one of sea control, not sure if the navy was following the Army strategy of vehicle procurement or the other way round.

tomuk wrote: ↑19 Feb 2023, 21:30

Repulse wrote: ↑19 Feb 2023, 20:16 It’s not an either / or. RN visits should be complementary with a broader strategy.

Also, sure you can park a larger frigate further off shore and send a helicopter. Two points, one given we haven’t done it for years, unlikely we can afford frigates and helicopters to cover the same ground. Second, it will not give the same effect - docking and being visible has value.

River B2 has a 4.4m draught, the Iver Huitfeldt with its weapons and radar fit has a draught of 5.3m, of all the port calls made on the current deployment I would guess there aren't many ports that a T31 couldn't have docked at too.

I look forward to your forthcoming trreatise on the numerous oceanic deep water ports in Polynesia, Melanesia and Micronesia....

wargame_insomniac wrote: ↑19 Feb 2023, 23:13

tomuk wrote: ↑19 Feb 2023, 21:30

Repulse wrote: ↑19 Feb 2023, 20:16 It’s not an either / or. RN visits should be complementary with a broader strategy.

Also, sure you can park a larger frigate further off shore and send a helicopter. Two points, one given we haven’t done it for years, unlikely we can afford frigates and helicopters to cover the same ground. Second, it will not give the same effect - docking and being visible has value.

River B2 has a 4.4m draught, the Iver Huitfeldt with its weapons and radar fit has a draught of 5.3m, of all the port calls made on the current deployment I would guess there aren't many ports that a T31 couldn't have docked at too.

I look forward to your forthcoming trreatise on the numerous oceanic deep water ports in Polynesia, Melanesia and Micronesia....

There is less than 1m difference in draught between a B2 and a T31. 5.3m is still less than 20ft.

wargame_insomniac wrote: ↑19 Feb 2023, 23:13

tomuk wrote: ↑19 Feb 2023, 21:30

Repulse wrote: ↑19 Feb 2023, 20:16 It’s not an either / or. RN visits should be complementary with a broader strategy.

Also, sure you can park a larger frigate further off shore and send a helicopter. Two points, one given we haven’t done it for years, unlikely we can afford frigates and helicopters to cover the same ground. Second, it will not give the same effect - docking and being visible has value.

River B2 has a 4.4m draught, the Iver Huitfeldt with its weapons and radar fit has a draught of 5.3m, of all the port calls made on the current deployment I would guess there aren't many ports that a T31 couldn't have docked at too.

I look forward to your forthcoming trreatise on the numerous oceanic deep water ports in Polynesia, Melanesia and Micronesia....

Well the cruise ships manage to make it….

HMS Spey in Thailand.

so what is the sailing time from Cambodia to Thailand whats the at sea days in the last 3 weeks say 15 with 6 days in port

SW1 wrote: ↑20 Feb 2023, 07:41

wargame_insomniac wrote: ↑19 Feb 2023, 23:13

tomuk wrote: ↑19 Feb 2023, 21:30

Repulse wrote: ↑19 Feb 2023, 20:16 It’s not an either / or. RN visits should be complementary with a broader strategy.

Also, sure you can park a larger frigate further off shore and send a helicopter. Two points, one given we haven’t done it for years, unlikely we can afford frigates and helicopters to cover the same ground. Second, it will not give the same effect - docking and being visible has value.

River B2 has a 4.4m draught, the Iver Huitfeldt with its weapons and radar fit has a draught of 5.3m, of all the port calls made on the current deployment I would guess there aren't many ports that a T31 couldn't have docked at too.

I look forward to your forthcoming trreatise on the numerous oceanic deep water ports in Polynesia, Melanesia and Micronesia....

Well the cruise ships manage to make it….

tomuk wrote: ↑19 Feb 2023, 21:30 River B2 has a 4.4m draught

I’ve seen it quoted as 3.8m

Repulse wrote: ↑20 Feb 2023, 20:20

tomuk wrote: ↑19 Feb 2023, 21:30 River B2 has a 4.4m draught

I’ve seen it quoted as 3.8m

I believe 3.8m is the figure for the smaller Batch 1s.

tomuk wrote: ↑20 Feb 2023, 20:31

Repulse wrote: ↑20 Feb 2023, 20:20

tomuk wrote: ↑19 Feb 2023, 21:30 River B2 has a 4.4m draught

I’ve seen it quoted as 3.8m

I believe 3.8m is the figure for the smaller Batch 1s.

3.8 is for the B1's

Tempest414 wrote: ↑20 Feb 2023, 22:18

tomuk wrote: ↑20 Feb 2023, 20:31

Repulse wrote: ↑20 Feb 2023, 20:20

tomuk wrote: ↑19 Feb 2023, 21:30 River B2 has a 4.4m draught

I’ve seen it quoted as 3.8m

I believe 3.8m is the figure for the smaller Batch 1s.

3.8 is for the B1's

Out of interest, where did you get your number from? Various sources including British Warships & Auxiliaries state 3.8m.

Repulse wrote: ↑21 Feb 2023, 06:37

Tempest414 wrote: ↑20 Feb 2023, 22:18

tomuk wrote: ↑20 Feb 2023, 20:31

Repulse wrote: ↑20 Feb 2023, 20:20

tomuk wrote: ↑19 Feb 2023, 21:30 River B2 has a 4.4m draught

I’ve seen it quoted as 3.8m

I believe 3.8m is the figure for the smaller Batch 1s.

3.8 is for the B1's

Out of interest, where did you get your number from? Various sources including British Warships & Auxiliaries state 3.8m.

NATO\RN HMS Trent fact sheet
https://mc.nato.int/resources/site1/Ge ... sheet.pdf.

Repulse wrote: ↑21 Feb 2023, 06:37

Tempest414 wrote: ↑20 Feb 2023, 22:18

tomuk wrote: ↑20 Feb 2023, 20:31

Repulse wrote: ↑20 Feb 2023, 20:20

tomuk wrote: ↑19 Feb 2023, 21:30 River B2 has a 4.4m draught

I’ve seen it quoted as 3.8m

I believe 3.8m is the figure for the smaller Batch 1s.

3.8 is for the B1's

Out of interest, where did you get your number from? Various sources including British Warships & Auxiliaries state 3.8m.

And 90% of those have the prefix B1 next to the 3.8 figure

A new proposal.

<background>
I have been thinking how to make RNZN decide to buy 2 (or 3) Rosyth-build T31 as their Te Kaha/Te Mana frigates replacement. One point is, the dry-dock of Devonport naval base in Auckland/NZ is operated by Babcock NZ, and they do upgrade of frigates of RNZN and French navy (although oriented only around ship-systems, including replacing their diesel gens to more powerful ones, while weapons-system upgrade is done at Canada).

So, by deepening NZ and UK navy relationships, and involving Babcock NZ for T31-NZ building process, UK may succeed in selling 2 (or 3) T31s to NZ, I hope.

<proposal>
Currently, River B2 OPV HMS Forth is undergoing her first long-maintenance at Gib. Supposedly, it will be followed by Medway, Tamar, Trent and Spey. In other words, there will be only 4 River B2s active for coming 3-4 years, I guess. At the same time, in 2025 (coincident with "3-4 years later"), 3 River B1 OPVs will be disbanded. As 5 T31 will be more avtive than 3 T23GPs, River B1 OPVs may not see replacements. But, I think "shortage of OPV" can be an issue from now to even after 2025.

At the same time, RNZN is facing lack of man-power, putting 2 OPVs and 1 IPV in extended readiness (while keeping 2 frigates, 1 MRV, 1 AOR, 1 diver-tender and 1 IPV active).

Then, how about RN leasing one of the 2 RNZN OPVs for 5 years (until 2028) and even longer? For example, lease HMNZS Wellington and rename it as HMS Endevour, to be operated under RN while ensign in Indo-Pacific region (not only Pacific). NZ's Otago-class OPV is a Vard-7 85 design. By Vard-7's nature, it is a merchant-ship-based design and thus (will be) easy to operate. It has a 25 mm gun, a few MGs, 2 RHIBs, a mission-deck with 15t-crane, and a SH-2G capable flight deck and hangar.

This will benefit NZ govermnet with the lease-fee. This will benefit RN by providing another OPV hull, enabling not-to-gap any 5 River B2s standing operations. Relation ship between RN and RNZN will be deeper. Operating NZ's OPV with RN ensign and crew will make many Indo-Pacific nations impressed with UK-NZ deep relation. The OPV will be annually maintained at NZ Auckland Calliope dock, by Babcock NZ.

This will also enable RN member to "deeply assess" Vard-7 OPV design (merchant-ship design based) and usefuleness of "an OPV with helicopter hangar". For NZ, this relation will inevitably increase "talks" with RN and RNZN members.

And, I hope these deeper relationship will eventually lead to NZ ordering 2 (or 3) T31s in 2030 or so...

Just a thought.

I think closer ties with RNZN is a good approach for the RN to pursue. It feels they are becoming a more distant partner, and with the advent of AUKUS could become more marginalised and prone to Chinese influence. I would perhaps suggest a jointly manned low level constabulary/influence ship(s) focused on the Pacific islands where Chinese influence is also on the rise.

In terms of which ships etc, I’m unsure. Personally, I see the need for 80-90m OPV/Sloops for the RN and a decent drumbeat of new ships, so am definitely in favour of pushing for B1 replacements. For me, in the next war (there will be one it’s just when) this type of ship could be built in a number of yards and would be the real RN scaling factor, Frigates and Destroyers would take much longer constrained by the current yard(s) - a modern day Flower type if you’d like.

donald_of_tokyo wrote: ↑26 Feb 2023, 06:28 <proposal>
Currently, River B2 OPV HMS Forth is undergoing her first long-maintenance at Gib. Supposedly, it will be followed by Medway, Tamar, Trent and Spey. In other words, there will be only 4 River B2s active for coming 3-4 years, I guess. At the same time, in 2025 (coincident with "3-4 years later"), 3 River B1 OPVs will be disbanded. As 5 T31 will be more avtive than 3 T23GPs, River B1 OPVs may not see replacements. But, I think "shortage of OPV" can be an issue from now to even after 2025.

At the same time, RNZN is facing lack of man-power, putting 2 OPVs and 1 IPV in extended readiness (while keeping 2 frigates, 1 MRV, 1 AOR, 1 diver-tender and 1 IPV active).

Then, how about RN leasing one of the 2 RNZN OPVs for 5 years (until 2028) and even longer? For example, lease HMNZS Wellington and rename it as HMS Endevour, to be operated under RN while ensign in Indo-Pacific region (not only Pacific). NZ's Otago-class OPV is a Vard-7 85 design. By Vard-7's nature, it is a merchant-ship-based design and thus (will be) easy to operate. It has a 25 mm gun, a few MGs, 2 RHIBs, a mission-deck with 15t-crane, and a SH-2G capable flight deck and hangar.

This will benefit NZ govermnet with the lease-fee. This will benefit RN by providing another OPV hull, enabling not-to-gap any 5 River B2s standing operations. Relation ship between RN and RNZN will be deeper. Operating NZ's OPV with RN ensign and crew will make many Indo-Pacific nations impressed with UK-NZ deep relation. The OPV will be annually maintained at NZ Auckland Calliope dock, by Babcock NZ.

This will also enable RN member to "deeply assess" Vard-7 OPV design (merchant-ship design based) and usefuleness of "an OPV with helicopter hangar". For NZ, this relation will inevitably increase "talks" with RN and RNZN members.

And, I hope these deeper relationship will eventually lead to NZ ordering 2 (or 3) T31s in 2030 or so...

Just a thought.

With close family in both Australia and New Zealand, I am especially keen for UK to build up stronger defence tis with both nations. AUKUS is a great start for former; my concern has long been how to do likewise with NZ given their lower focus on Defence Spending, and their struggle to man their existing ships.

With increase in China for both regional aggressiveness and Naval power projection, my concern spread further north to the Melanesian and Polynesian islands (I am assuming that greater US involvement in Micronesia would look after the more northerly of Pacific Island groups). Now although UK does have a British Overseas Territory in Pitcairn Islands, we can't afford to have a permanent base there or even regular deployment of a PV.

Therefore anything we have to do in the region would be in partnership with Aus and NZ, not to mention France and US and the larger island states. I like programmes such as the smaller Guardian-class patrol boats provided to 13 of the pacific islands as part of the Australian Government's Pacific Maritime Security Program. It would be great if the Pitcairn Islands could provide sufficient crew for even one of these 40m Patrol Boats to patrol their maritime EEZ.

AUKUS has seen RAN crew starting to operate on RN SSN's as part of building towards eventually crewing their own boats. I would be happy if we could do something similar with RNZN, whether it is our leasing their uncrewed OPV when our own River Batch 2's get their first long-maintenance in rotation.

There is scope for RN ordering new OPV of around 80m-85m size to replace the River B1s. Whether we went for a Yard design like the RNZN OPV, Lürssen like the RAN Arafura Class OPV, or even Damen (after the recent experience of XV Patrick Blackett). If these were to concentrate on British Overseas Territories fishery protection, anti-drug smuggling and general patrolling. this may free up River B2's and eventually Type 31 Frigates for proper warships duties.

Repulse wrote: ↑26 Feb 2023, 08:42 I think closer ties with RNZN is a good approach for the RN to pursue. It feels they are becoming a more distant partner, and with the advent of AUKUS could become more marginalised and prone to Chinese influence. I would perhaps suggest a jointly manned low level constabulary/influence ship(s) focused on the Pacific islands where Chinese influence is also on the rise.

In terms of which ships etc, I’m unsure. Personally, I see the need for 80-90m OPV/Sloops for the RN and a decent drumbeat of new ships, so am definitely in favour of pushing for B1 replacements. For me, in the next war (there will be one it’s just when) this type of ship could be built in a number of yards and would be the real RN scaling factor, Frigates and Destroyers would take much longer constrained by the current yard(s) - a modern day Flower type if you’d like.

I am fine with that size of ship being ordered to replace the River B1's. I do agree with the need of low level constabulary/influence ship(s) focused on the Pacific islands - we cant do it alone but would be great if we could do it along with RAN, RNZN and also French / US,

If you are talking such ships in a more wartime role, then I guess as a "modern day Flower type" that they would be used to protect merchant shipping convoys? What would they need to protect the mecrhant ships against threats in air, on sea, under sea??

So would these need sonar and some way of attacking submarines? What about AAW or ASuW sensors and weaponry?

How is a smaller OPV than the B2 rivers with presumably a similar or smaller weapons fit eg 2D radar and 30mm canon meant to have wartime role?
If your going to scale up why not build more T31s which is an actual warship and has been optimised to be built in commercial yards by Maersk.

tomuk wrote: ↑26 Feb 2023, 20:17 How is a smaller OPV than the B2 rivers with presumably a similar or smaller weapons fit eg 2D radar and 30mm canon meant to have wartime role?
If your going to scale up why not build more T31s which is an actual warship and has been optimised to be built in commercial yards by Maersk.

Because there are few yards that could build them in the UK, and no we shouldn’t be reliant on overseas yards.

Appledore for example can build a 90m ship, it could do 110m but it’s far from comfortable.

A 90m ship with a 3D Radar, 57mm gun, containerised 12 cell CAMM cell launcher, UAVs (with Dipping Sonar and StingRays) and hull mounted sonar could contribute to a Atlantic War III, especially when paired with other MPA, UUV, SSN and ASW Frigate assets.

Repulse wrote: ↑26 Feb 2023, 20:51

tomuk wrote: ↑26 Feb 2023, 20:17 How is a smaller OPV than the B2 rivers with presumably a similar or smaller weapons fit eg 2D radar and 30mm canon meant to have wartime role?
If your going to scale up why not build more T31s which is an actual warship and has been optimised to be built in commercial yards by Maersk.

Because there are few yards that could build them in the UK, and no we shouldn’t be reliant on overseas yards.

Appledore for example can build a 90m ship, it could do 110m but it’s far from comfortable.

A 90m ship with a 3D Radar, 57mm gun, containerised 12 cell CAMM cell launcher, UAVs (with Dipping Sonar and StingRays) and hull mounted sonar could contribute to a Atlantic War III, especially when paired with other MPA, UUV, SSN and ASW Frigate assets.

So you are not prposing an OPV or Sloop then but a Corvette and packing all of that into 90m isn't going to be cheap or easy.

Is this I want a surface ship built in England and any argument will do to achieve that?

tomuk wrote: ↑26 Feb 2023, 20:17 How is a smaller OPV than the B2 rivers with presumably a similar or smaller weapons fit eg 2D radar and 30mm canon meant to have wartime role?
If your going to scale up why not build more T31s which is an actual warship and has been optimised to be built in commercial yards by Maersk.

Because I believe in using OPV for OPV tasks, and I believe in using warships for warships tasks.
Thus I want cheaper OPV and to use that money to invest in upgrading our warships.
Just my opinion.

Moved across

wargame_insomniac wrote: ↑26 Feb 2023, 18:20

donald_of_tokyo wrote: ↑26 Feb 2023, 06:28 <proposal>
Currently, River B2 OPV HMS Forth is undergoing her first long-maintenance at Gib. Supposedly, it will be followed by Medway, Tamar, Trent and Spey. In other words, there will be only 4 River B2s active for coming 3-4 years, I guess. At the same time, in 2025 (coincident with "3-4 years later"), 3 River B1 OPVs will be disbanded. As 5 T31 will be more avtive than 3 T23GPs, River B1 OPVs may not see replacements. But, I think "shortage of OPV" can be an issue from now to even after 2025.

At the same time, RNZN is facing lack of man-power, putting 2 OPVs and 1 IPV in extended readiness (while keeping 2 frigates, 1 MRV, 1 AOR, 1 diver-tender and 1 IPV active).

Then, how about RN leasing one of the 2 RNZN OPVs for 5 years (until 2028) and even longer? For example, lease HMNZS Wellington and rename it as HMS Endevour, to be operated under RN while ensign in Indo-Pacific region (not only Pacific). NZ's Otago-class OPV is a Vard-7 85 design. By Vard-7's nature, it is a merchant-ship-based design and thus (will be) easy to operate. It has a 25 mm gun, a few MGs, 2 RHIBs, a mission-deck with 15t-crane, and a SH-2G capable flight deck and hangar.

This will benefit NZ govermnet with the lease-fee. This will benefit RN by providing another OPV hull, enabling not-to-gap any 5 River B2s standing operations. Relation ship between RN and RNZN will be deeper. Operating NZ's OPV with RN ensign and crew will make many Indo-Pacific nations impressed with UK-NZ deep relation. The OPV will be annually maintained at NZ Auckland Calliope dock, by Babcock NZ.

This will also enable RN member to "deeply assess" Vard-7 OPV design (merchant-ship design based) and usefuleness of "an OPV with helicopter hangar". For NZ, this relation will inevitably increase "talks" with RN and RNZN members.

And, I hope these deeper relationship will eventually lead to NZ ordering 2 (or 3) T31s in 2030 or so...

Just a thought.

... I would be happy if we could do something similar with RNZN, whether it is our leasing their uncrewed OPV when our own River Batch 2's get their first long-maintenance in rotation.

This is all the heart of my proposal. Note, this approach can take place NOW. If immediate action is taken, by this summer the Vard7 85 OPV (NZ-origin) renamed with "HMS" (not "HMNZS") and operated by RN will be visiting east Africa, ASEAN, India, as well as Polinesia. Big political impact, and gaping nothing RN did in 2022.

Again, my point is, RN can operate 8 OPV even when one of the River B2s are in long maintenance, and it can ALSO enhance close ties between RN and RNZN.

Talk about River B1 replacement is a completely different story.