River Class (OPV) (RN)

[Repulse]

If CEPP and CASD are the priority, and the core of the RN’s war fighting capability, then we should be giving them the best escorts we can afford. This means T45s with BMD, the world’s best ASW platform, the T26, combined with the worlds best SSN.

As @Donald-san notes, the B2s will cover the presence role well, especially with land based (or RFA) air support, as the current deployments show.

[Tempest414]

A maybe messy but doable way forward is to buy and fit 2 x 57mm guns to two B'2's for use EoS and when type 31 4 and 5 are coming on line remove them from the B2's and arm them as needed to take over from the B1's

As for NSM 200 million from the I-SSGW should buy 10 sets allowing 6 for Type 45 and 4 for type 31

[donald_of_tokyo]

The simple fact is the B2's are a stop gap until the T-31s come in end of and they will be ask to carry out tasks they have no business doing and once the type 31 comes in the B2's will replace the B1's. With this in mind two of the B2's should be fitted with 57mm and given containerized UAV's to allow them to work EoS and once the type 31's come in these ships should replace the ships on FGS and AP-N leaving the remaining 3 to carry out UK EEZ duties

I am not sure if this is "fact" in any sense, but I agree it is interesting viewpoint.

1: Pushing this idea in its extreme, how about
- disband 3 T23 GP now, and say "3 of the 5 River B2 will temporally replace them as a stop-gap", while 2 will be in Falkland and Caribbean".
- then 5 T31 will replace 2 remaining T23GPs (to be disbanded) and then 3 RB2s. The latter will replace 3 River B1s (to be disbanded).

2: This will provide
- "cut" of 3 escorts for a moment to handle COVID19 recession, but with vision to come back to the same number "later".
- this will ALSO enable delaying T31 build by ~3 years, which will technically relax its risk (schedule risk), normalize Babcock Rosyths' man-power = make it sustainable longer, and reducing the immediate annual build cost of T31.

3: And, if so, can River B2 "borrow" the armaments prepared for T31 for a moment (~5-7 years). Say, mount the five 57 mm guns on 5 RB2s, and "move" them to the 5 T31s later. (EDIT; with simple FCS and CMS = for low cost, the 57mm gun won't be "fully" configured, but with 3P ammo (which I believe is already "normal" rounds for them), it will provide good anti-surface (boats) and low-end anti-air (drones) capability).

EDIT: Tempest414-san has already commented the same idea ...

[Repulse]

Given that the B2s will be fulfilling the forward presence role for a period of time, perhaps better to maximise (sensibly) their potential and slow the commissioning of the T31. Could still keep the build rate the same, by supporting sales to allies as part of the new UK Global Strategy.

What can’t be slowed is the T26 build, as there is no alternative.

[jedibeeftrix]

A maybe messy but doable way forward is to buy and fit 2 x 57mm guns to two B'2's for use EoS and when type 31 4 and 5 are coming on line remove them from the B2's and arm them as needed to take over from the B1's

As for NSM 200 million from the I-SSGW should buy 10 sets allowing 6 for Type 45 and 4 for type 31

Why is everyone leaping to expensive 57mm guns, when if T31 goes ahead we'll already have a large install base of the cheaper bofors 40mm?

[donald_of_tokyo]

Why is everyone leaping to expensive 57mm guns, when if T31 goes ahead we'll already have a large install base of the cheaper bofors 40mm?

Not sure for others. But for me, 40 mm 3P does not provide "leap in capability" compared to a 30mm gun if added with LMM. In other words, adding LMM to existing 30mm guns looks simpler, more attractive and maybe cheaper than introducing a 40 mm 3P guns? (might be wrong, and if so, yes 40mm 3P is also a good candidate, I agree).

[Tempest414]

Why is everyone leaping to expensive 57mm guns, when if T31 goes ahead we'll already have a large install base of the cheaper bofors 40mm?

I would agree and have said in the past that 40mm would be a good gun for the OPV's / MCM's however if we were to fit 57mm in the short term and then move them on to the type 31 the cost would be in the fitting and refitting as the gun them self would have been bought anyway however again the gun would have to come off for servicing anyway

[Jensy]

Why is everyone leaping to expensive 57mm guns, when if T31 goes ahead we'll already have a large install base of the cheaper bofors 40mm?

I would agree and have said in the past that 40mm would be a good gun for the OPV's / MCM's however if we were to fit 57mm in the short term and then move them on to the type 31 the cost would be in the fitting and refitting as the gun them self would have been bought anyway however again the gun would have to come off for servicing anyway

I was very much in the 'stick a 57mm on anything bigger than HMS Gleaner' camp until Ron5 pointed something out the other day when I suggested twin 57mm fitted upfront on the Type 31.


(40mm and 57mm upfront)

That is how absolutely massive the Bofors 57mm mk.110 is. Much larger than the BAE Mk45 5" or even the latest Oto Merala 76mm, which is itself considerably bigger than the one fitted to HTMS Krabi.

Whilst I'd still prefer the 57mm (if the cost didn't cause too much pain for the RN elsewhere) I'm not entirely sure the Rivers would have the space or if their gun mountings could even support it, without major modification.

By comparison the 40mm is incredibly compact and still has sizeable magazines, so doesn't require anything below deck.

[RichardIC]

That is how absolutely massive the Bofors 57mm mk.110 is. Much larger than the BAE Mk45 5" or even the latest Oto Merala 76mm, which is itself considerably bigger than the one fitted to HTMS Krabi.

I'm not quite sure what you're looking at. From the manufacturer's own datasheets.

57mm mk110 Empty weight. 6,800 kg
Oto 76/62. Empty weight. 7,900 kg
127mm mk 45. Empty weight. 21,900 kg

https://www.baesystems.com/en/download- ... 371489.pdf
https://www.leonardocompany.com/documen ... 8987745884
https://www.baesystems.com/en/download- ... 687963.pdf

[RichardIC]

By comparison the 40mm is incredibly compact and still has sizeable magazines, so doesn't require anything below deck.

For the sake of completeness

40mm mk 4 Empty weight 2,300 kg
https://www.baesystems.com/en/download- ... 371622.pdf

I keep hearing this claim that the 40mm is non-deck penetrating/ doesn't require anything below deck.

I think it's technically true only if you don't intend reloading the intermediate magazine or are happy to reload it manually via the service hatch at the rear of the turret having previously manhandled the ammunition from the ship magazine.

Reloading from below deck seems more practical.



It holds 100 rounds on the turret which is hardly a huge capacity.

[SKB]

(@MaggsCaseyKelly) 7th September 2020

Anyone care to guess where HMS Tamar is right now?!

[Tempest414]

Reloading from below deck seems more practical.

And we know that the B2's have the space under the front mount

[Ron5]

That is how absolutely massive the Bofors 57mm mk.110 is. Much larger than the BAE Mk45 5" or even the latest Oto Merala 76mm, which is itself considerably bigger than the one fitted to HTMS Krabi.

I'm not quite sure what you're looking at. From the manufacturer's own datasheets.

57mm mk110 Empty weight. 6,800 kg
Oto 76/62. Empty weight. 7,900 kg
127mm mk 45. Empty weight. 21,900 kg

https://www.baesystems.com/en/download- ... 371489.pdf
https://www.leonardocompany.com/documen ... 8987745884
https://www.baesystems.com/en/download- ... 687963.pdf

Size not weight.

[Ron5]

By comparison the 40mm is incredibly compact and still has sizeable magazines, so doesn't require anything below deck.

For the sake of completeness

40mm mk 4 Empty weight 2,300 kg
https://www.baesystems.com/en/download- ... 371622.pdf

I keep hearing this claim that the 40mm is non-deck penetrating/ doesn't require anything below deck.

I think it's technically true only if you don't intend reloading the intermediate magazine or are happy to reload it manually via the service hatch at the rear of the turret having previously manhandled the ammunition from the ship magazine.

Reloading from below deck seems more practical.



It holds 100 rounds on the turret which is hardly a huge capacity.

The gun come in two flavors: deck penetrating and reloadable under cover, and not. That's why it says "option" in the diagram.

I think it's technically true only if you don't intend reloading the intermediate magazine or are happy to reload it manually via the service hatch at the rear of the turret having previously manhandled the ammunition from the ship magazine.

That's how the DS30 is loaded. That's how Phalanx is reloaded.

[Digger22]

Now if you could combine the 40mm with LMM, then your talking.

[RichardIC]

That's how the DS30 is loaded. That's how Phalanx is reloaded.

Absolutely. But does that make it optimum? Seems better to avoid if possible.

Now if you could combine the 40mm with LMM, then your talking.

I don't see why LMM paniers couldn't be attached to any mount as long as the recoil isn't too great to shake the thing to pieces - which it may be. I think it's the placement of the director that is the issue.

[RichardIC]

Size not weight.

Above deck? below deck? width? Are you saying it has a larger overall footprint?

[Tempest414]

Now if you could combine the 40mm with LMM, then your talking.

I may be wrong but a 40mm has a longer range and the same stopping power as LMM. If this is right why bother with a few LMM on a 40mm mount

[RichardIC]

I may be wrong but a 40mm has a longer range and the same stopping power as LMM. If this is right why bother with a few LMM on a 40mm mount

Good point, well made. And a 40mm round will be a good deal cheaper.

[Digger22]

I didn't realise 40mm rounds were guided!

[RichardIC]

I'm keeping out of this one.

[Caribbean]

I think LMM is probably better suited to combining with a smaller calibre gun in an automated mount like ASCG (and probably half-a-dozen others), for use as secondary armament (or primary on smaller vessels). That would allow the secondary armament to "step up" to handle a more difficult target when the primary is already engaged dealing with something else (or simply add precision fire when needed)

[Ron5]

Size not weight.

Above deck? below deck? width? Are you saying it has a larger overall footprint?

Didn't say it was larger, said it was big, bigger than you might expect. And yes, footprint.

[Tempest414]

I didn't realise 40mm rounds were guided!

I would first ask what you want to counter that you think a 40mm with 3P can't

[The Armchair Soldier]

Alright guys, feel free to take your discussion to the escorts thread, otherwise let's keep this one for the River-class OPVs (and keep the fantasising to a minimum).