Offshore Patrol Vessels

rampant

LE
Kit Reviewer
Book Reviewer
Go and give your head a wobble, Bringing facts and logic to the debate in the face of extreme googlefu
Seriously, there's only a slack handful of these cannon in existence at this moment in time. That will change over the next few years though.
 
Seriously, there's only a slack handful of these cannon in existence at this moment in time. That will change over the next few years though.
As of June 2018 they'd delivered 240 of them according to Janes. However, compared to the thousands of conventional 30 and 40mm gun, and umpteen million rounds of accompanying ammo, you are quite right in pointing out that it's really early days for CTA.
 
The RapidFire 40CTA system has no CIWS capability against missiles, unlike the Bofors Mk4. It’s reaction time is a not very sprightly 4.5 seconds vs a rather more impressive 0.5 second reaction time for the Mk4 Bofors.
Nexter only claim a max effective range of 2500m against surface targets, 4000m against aircraft using programmable bullets.

so, a much dearer gun, phenomenally dearer ammunition, limited engagement capability... It is what it is, a ‘Navalised’ tank turret, not a properly designed naval gun system.
 
The article mentions the Bofors 40mm as the potential system to up-gun the Batch 2s but I wonder if the navalised version of the CTAS 40mm might also turn out to be an option?

The French seem to be intending to use it in some fashion on some of their units.


(it's in French but Google Translate mostly sorts that out)
The article is laying some options for what is possible, rather than what makes the most sense. The 40mm Bofors is really just a place holder for showing a simpler gun upgrade in contrast to the 57mm gun used in the other two options.

It supposedly "can act both as a close-in weapons systems for air and missile defence or against surface targets such as small boat swarms." It's questionable though as to just how useful it would be in that role against modern anti-ship missiles. To do anything useful there against modern threats you might need something more advanced, which in turn might need a radar upgrade. I don't know if there is something cheaper than Sea Ceptor, but on the other hand I don't know if a 40mm gun on its own will do much more for you than prayer would if a Brahmos is inbound.

For the "small boat swarms" a 30mm gun can still do a lot to discourage them. If you need more punch than that, there was a recent test of a system which hung a set of Martlet missiles off a 30mm gun mount. Something like that could be added as required for a particular theatre according to operational requirements.

What did sound very useful though is the rotary wing UAV system the article mentioned, which could be deployed in a container. Something like that would help an OPV to do OPV type tasks even if there were no requirement to make the ship a bit more bellicose in general. I would not be surprised if these were deployed on the OPVs in future. The fact that they are deployed by dropping a container into place means there isn't much, if any, change required to the ship so it could be done at short notice.
 

Flight

LE
Book Reviewer
Someone must have hacked Meerkat's account...
 
Anything bar a very high end air defence Destroyer is going to have a very bad time defending itself against a Brahmos or SS-N-27, thats the very high end. The real world threat for a flag wagging B2 OPVs - and the T31 that will replace them - will be things knock off Exocets or Silkworms. If the opposition have properly serious ASMs, B2’s will not be out playing.
 

Flight

LE
Book Reviewer
How could a River knock down a silkworm or similar?

Chances of hitting an ASM with it's 30mm must be minute...
 

jrwlynch

LE
Book Reviewer
How could a River knock down a silkworm or similar?

Chances of hitting an ASM with it's 30mm must be minute...
It could be upgunned with a 76mm OTO-Melara which is an Invincible Shield of Missile Defence, able to reliably bring down entire salvos of ASCMs with a wide enough isoleth to protect consorts too.

And you should see what it can do as an offensive weapon...


 

Cold_Collation

LE
Book Reviewer
It could be upgunned with a 76mm OTO-Melara which is an Invincible Shield of Missile Defence, able to reliably bring down entire salvos of ASCMs with a wide enough isoleth to protect consorts too.

And you should see what it can do as an offensive weapon...


Look, if you're not going to take things seriously...
 
How could a River knock down a silkworm or similar?

Chances of hitting an ASM with it's 30mm must be minute...
Probably not a good idea to send them where there's a good chance of meeting one without something beefier close by.
That said, we removed the HS goalkeepers form Albion and Bulwark so I wonder if it would be worth dragging them out of stores. Yes, the design pierces the deck but they do sport 30mm "wall of steel" gun.
Just a thought.
 

Yokel

LE
Probably not a good idea to send them where there's a good chance of meeting one without something beefier close by.
That said, we removed the HS goalkeepers form Albion and Bulwark so I wonder if it would be worth dragging them out of stores. Yes, the design pierces the deck but they do sport 30mm "wall of steel" gun.
Just a thought.
Perhaps installing Phalanx would be justifiable for certain theatres, but Goalkeeper is no longer in RN service. It was also complex to integrate.

Anyway - it has been confirmed that the third of the Batch 2 RCOPVs will be forward based in Gibraltar for maritime security operations and presence in the Mediterranean.
 
It could be upgunned with a 76mm OTO-Melara which is an Invincible Shield of Missile Defence, able to reliably bring down entire salvos of ASCMs with a wide enough isoleth to protect consorts too.

And you should see what it can do as an offensive weapon...


well I hate to break this to you, but them what choose guns for Her Majesties war canoes has decided that actually, yes, modern intermediate calibre guns with 3P ammunition do indeed provide a very credible AAA and anti missile defence.

of course it’s possible that the RN has joined the multitude of other navies adopting such guns purely on the basis of sales brochures, or maybe not, and they actually are very effective as the RN states.
now, in between your hyperbole, nope, neither B2 OPVs or T31‘s have, or are expected to provide any air defence capability except to themselves - they don’t protect ‘consorts’, because, they are expressly not war fighting vessels.

of course the logical progression now the RN has taken the plunge with the Mk110, is to fast track the 4.5“ - zero AA capability - to the great scrapyard in the Sky and replace them ASAP With the Mk110 as per the RCN on their major surface combatants.
 
Probably not a good idea to send them where there's a good chance of meeting one without something beefier close by.
That said, we removed the HS goalkeepers form Albion and Bulwark so I wonder if it would be worth dragging them out of stores. Yes, the design pierces the deck but they do sport 30mm "wall of steel" gun.
Just a thought.
nope, outdated, huge, very deck penetrating, needs to be built In to a fairly large ship, needs lots of looking after.
The future isnt Phalanx, it’s the Mk4 40mm Bofors.
 

jrwlynch

LE
Book Reviewer
well I hate to break this to you, but them what choose guns for Her Majesties war canoes has decided that actually, yes, modern intermediate calibre guns with 3P ammunition do indeed provide a very credible AAA and anti missile defence.
Source, please.

Oh, this is an unattributable, untraceable claim? Based on no evidence whatsoever? In fact, you and your proctologist just extracted it from That Place Where The Sun Shineth Not?

Thought so. Go read the actual survivability analysis conducted during the T31 competition and see what threats it was assessed against, and what weapons were and weren't considered useful against them.

I'll wait while you do that...

now, in between your hyperbole, nope, neither B2 OPVs or T31‘s have, or are expected to provide any air defence capability except to themselves - they don’t protect ‘consorts’, because, they are expressly not war fighting vessels.
Wrong again - go read the T31 Key User Requirements. There's a big area between "all out war" and "stuff an OPV does".

Seriously, why are you so determined to act the hoofwanking thundercµnt in public? Do you enjoy making a fool of yourself?

of course the logical progression now the RN has taken the plunge with the Mk110, is to fast track the 4.5“ - zero AA capability - to the great scrapyard in the Sky and replace them ASAP With the Mk110 as per the RCN on their major surface combatants.
Which rely, for their air defence, on the Enhanced Sea Sparrow missile and the Mk 15 Close In Weapon System: the 57mm gun is in the "hopeful best effort" category.

But then I've actually read MARTIs for the Halifax-class frigates...
 
Source, please.

Oh, this is an unattributable, untraceable claim? Based on no evidence whatsoever? In fact, you and your proctologist just extracted it from That Place Where The Sun Shineth Not?

Thought so. Go read the actual survivability analysis conducted during the T31 competition and see what threats it was assessed against, and what weapons were and weren't considered useful against them.

I'll wait while you do that...



Wrong again - go read the T31 Key User Requirements. There's a big area between "all out war" and "stuff an OPV does".

Seriously, why are you so determined to act the hoofwanking thundercµnt in public? Do you enjoy making a fool of yourself?



Which rely, for their air defence, on the Enhanced Sea Sparrow missile and the Mk 15 Close In Weapon System: the 57mm gun is in the "hopeful best effort" category.

But then I've actually read MARTIs for the Halifax-class frigates...
Don’t hold your breath on any real world evidence, I am still waiting the claim he made about being gifted MV22 and M1a2.
 
yes, modern intermediate calibre guns with 3P ammunition do indeed provide a very credible AAA and anti missile defence.
Errrr. not they don't. Not unless "credible" is another word for "pray really hard".

Every single army with the option, has given up on gun-based VSHORAD because it doesn't have the range to deal with an attack helicopter, far less a fast jet or missile. Every single Navy with the option has given up on Phalanx for serious anti-missile defence (and switched to missiles) because the best fire control in the world can't get more than a couple of rounds off against a supersonic missile before it hits; and because the turret can only point in one direction at a time.

Let's see. SUNBURN is doing Mach 2; call it 750m/s for cash. It enters gun range at 5km, and will hit the ship seven seconds later. First round of 40mm heads out towards it at 1000m/s; has a chance of a hit at the 3km mark. Assuming there's a tracker, it gets a correction slightly beforehand, and applies it once it knows how far off it is. Correction applied while missile at 3km, next round can only intercept at 1500m. Correction applied, next round can only intercept at 600m. Next round, at 300m. Next, at 120m. After that it's kind of pointless, you've still got a couple of tons of missile hitting you altogether or in large chunks.

Saying "300rpm is lots of rounds", like your opinions, rather misses the point. The correction is what matters; the five to ten rounds flying behind the point man are going to go to exactly the same place. Your 40mm will get only five corrections in before the missile hits. Five chances for your 40mm round to take out a 3-tonne missile. Bit of a sod if it can manoeuvre as it comes in... Now recalculate that as if (in a couple of years) you're facing a BrahMos-II, coming in at over 2000m/s. You might get only three corrected rounds off (corrections at 1700m, 600m, 200m).

Now do you see why Phalanx won't cut it against supersonic missiles? And yet, you insist differently.
 

jrwlynch

LE
Book Reviewer
Let's see. SUNBURN is doing Mach 2; call it 750m/s for cash. It enters gun range at 5km, and will hit the ship seven seconds later. First round of 40mm heads out towards it at 1000m/s; has a chance of a hit at the 3km mark. Assuming there's a tracker, it gets a correction slightly beforehand, and applies it once it knows how far off it is. Correction applied while missile at 3km, next round can only intercept at 1500m. Correction applied, next round can only intercept at 600m. Next round, at 300m. Next, at 120m. After that it's kind of pointless, you've still got a couple of tons of missile hitting you altogether or in large chunks.
A couple of issues that keeps CIWS in the game, are fire control, terminal effect, and engagement range.

Fire control: Phalanx (and Goalkeeper in its day) uses open-loop tracking: instead of waiting for the projectile and target to get to Closest Point of Approach (i.e. "how much did I miss by?" and only then dialling in a correction, CIWS tracks the outgoing rounds as well as the incoming threat, works out how much it's going to miss by, and adjusts the aimpoint based on that; so, the gun's putting more rounds closer to the target and getting more hits.

Terminal effect: CIWS is putting APDS penetrators into the nose of the missile, rather than pelting its side with fragmentation, which does more damage. A supersonic missile is in more trouble from hits, ironically: a Phalanx penetrator hits a Sunburn with twice the kinetic energy (relative velocity at impact, ~1600m/s versus 1100m/s) and the Mach 2+ airflow at sea level is unforgiving of disruption.

Engagement range: what turns "no chance" into "some chance" against a manoeuvring supersonic target, is that by the time Phalanx is opening fire, the threat has to have stopped weaving; it's getting into minimum range for its seeker and needs to stop jinking around and make its final approach to you. (Unlike, say, a 76mm gun, which at its theoretically effective open-fire range is trying to shoot at a Mach 2 target making the sort of evasive weave that would pull the wings off a F-16) so in those last seconds it's a steady target.

Supersonic speed's no guarantee of immunity - after all, the original Phalanx had to be making a useful effort against AS-4, AS-6 and SS-N-19 back in the day - and Phalanx, especially Block 1B, still has a lot of value for its specific niche. (Hence why you'll see Phalanx mounts port and starboard on the Type 26 models, and QNLZ has a couple of mounts already)
T26 model.jpg

QNLZ Phalanx.jpg


But that niche is a final line of defence against leakers... it's there as a backup because the ship it's defending is worth that investment.

And it's a specialised system: in an ASMD engagement, without that open-loop tracking, (as Gravelbelly describes), you're mostly wasting rounds on empty sky. Which is back to why you might still see dedicated gun-based CIWS, but other gun systems are in the "have a go, can't hurt" category (and even our venerable Mk 8 4.5" has guidance on how to use it in that case)
 
Was there ever a 25 or 30mm phalanx ?
I know Goalkeeper was 30mm, so wondering if phalanx went bigger.
 

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