Dutch Expeditionary Submarine Programme

[Titus K]

Article is behind a paywall, so i'll only post the pictures provided by the dutch ministry of defence.
https://premium.marineschepen.nl/voor-het-eerst-een-kijkje-in-de-orka-onderzeeboot/
The flexible torpedo room is definitely impressive with space for 30 weapons
Also there is space behind the sail for a special force module

 

[Scott Kenny]

30 weapons? That's a decent step up from a 688 or Virginia's torpedo room.

Still leaves issues with the ability to launch a threatening volley of AShMs, though. Only 4 tubes, so at best you're launching 3x Exocets (because you gotta keep 1 tube with a torpedo in it for emergencies).

 

[TomS]

30 weapons? That's a decent step up from a 688 or Virginia's torpedo room.

Still leaves issues with the ability to launch a threatening volley of AShMs, though. Only 4 tubes, so at best you're launching 3x Exocets (because you gotta keep 1 tube with a torpedo in it for emergencies).

6 tubes, so you can volley 5 AShM, which is a decent number.

I know the official sources are saying 30 weapons but I can't get the diagrams to match up. The torpedo room image in post #41 shows 16 skids (8 stacks of 2), plus the 6 tubes, which is 22 total. Is there a third layer of weapons above the ones shown in the illustrations? And even if there is, you'll need a couple of empty slots if the goal is to be able to load and fire them in any order.

 

[tychosis]

I know the official sources are saying 30 weapons but I can't get the diagrams to match up. The torpedo room image in post #41 shows 16 skids (8 stacks of 2), plus the 6 tubes, which is 22 total.

"30 weapons" likely includes shorter weapons like SLMMs and doesn't actually mean 30 full-length HWTs.

 

[Scott Kenny]

6 tubes, so you can volley 5 AShM, which is a decent number.

They added 2 tubes over the Suffrens?

*blink*

So they did!

I know the official sources are saying 30 weapons but I can't get the diagrams to match up. The torpedo room image in post #41 shows 16 skids (8 stacks of 2), plus the 6 tubes, which is 22 total. Is there a third layer of weapons above the ones shown in the illustrations? And even if there is, you'll need a couple of empty slots if the goal is to be able to load and fire them in any order.

I would expect the stows to be 3 high so you can go straight from stow into the torpedo tube. So that gets us to 30 if we count the weapons in the tubes as well. Otherwise it's the 688/774 standard ~24 weapons.

But man I really do NOT like that 4-over-2 torpedo tube layout. With the lower tubes staggered from where the upper tubes are, you would have to shift the weapons sideways between two stows to load, instead of pushing straight forward out of the stow like you do for the upper tubes.

I suspect that the lower tubes will end up as the "snapshot" tubes while a missile attack would be launched out of the 4 upper tubes.

"30 weapons" likely includes shorter weapons like SLMMs and doesn't actually mean 30 full-length HWTs.

Not usually. 30 weapons is full length torpedoes and cruise missiles!

Where they do appear to be stretching the truth a bit is in counting what's in the torpedo tubes in addition to what's in the stows. If we're counting that way, an Ohio-class could carry 17 weapons.

Also, if you stack the racks 3 high instead of the 2-high like the illustration in post 41 shows, you get 8x3=24 plus the 6 tubes.

 

[Titus K]

I know the official sources are saying 30 weapons but I can't get the diagrams to match up. The torpedo room image in post #41 shows 16 skids (8 stacks of 2), plus the 6 tubes, which is 22 total. Is there a third layer of weapons above the ones shown in the illustrations? And even if there is, you'll need a couple of empty slots if the goal is to be able to load and fire them in any order.

It's 30 full length. It was directly communicated by Naval Group, but like you i cound't understand how they managed to reach that number

I think that the ceiling height in the Orka is significantly greater than in the Suffren, which means you should be able to add an additional level of weapon storage in the Orka... but there is no render showing it, wich is indeed weird

Layout in Suffren : 5 per side on 2 levels --> so 20 weapons stored + 4 loaded = 24
Layout in Orka : 4 per side on 3 levels --> so 24 weapons stored + 6 loaded = 30

When you compare the Orka diagrams, the ceiling height appears noticeably greater than in the Suffren.
In this video at ~23, the commander’s head is almost touching the ceiling, which shows how limited the vertical space is on the Suffren comapred to the Orka renders

View: https://youtu.be/5TJbSsvNwGI?si=5rc9X388AJyYBOzC&t=1432

 

[TomS]

But man I really do NOT like that 4-over-2 torpedo tube layout. With the lower tubes staggered from where the upper tubes are, you would have to shift the weapons sideways between two stows to load, instead of pushing straight forward out of the stow like you do for the upper tubes.

I think they all line up. On each side, the inboard top tube lines up to the innermost column of stows, lower tube lines up to the next column outboard, and the outer top tube lines up to the third column, with the fourth column being a deep reserve. But it's going to be one heck of a puzzle-solving evolution if you need to load something that isn't already in line behind the empty tube.

 

[Titus K]

I think they all line up. On each side, the inboard top tube lines up to the innermost column of stows, lower tube lines up to the next column outboard, and the outer top tube lines up to the third column, with the fourth column being a deep reserve. But it's going to be one heck of a puzzle-solving evolution if you need to load something that isn't already in line behind the empty tube.

Yes, what I gather from the renders, in a 24 stored weapons configuration, so 3 weapons stacked instead of 2 as shown in the renders.
"O" showing where the torpedo tubes line up with the stored weapons

 

[Scott Kenny]

I think they all line up. On each side, the inboard top tube lines up to the innermost column of stows, lower tube lines up to the next column outboard, and the outer top tube lines up to the third column, with the fourth column being a deep reserve.

Combined response:

Yes, what I gather from the renders, in a 24 stored weapons configuration, so 3 weapons stacked instead of 2 as shown in the renders.
"O" showing where the torpedo tubes line up with the stored weapons

Okay, if that is how they do line up it works.

Not sure I like it, but it would work.

But it's going to be one heck of a puzzle-solving evolution if you need to load something that isn't already in line behind the empty tube.

Always is. It's why the USN doesn't count the torpedo tubes as part of the potential load. You get a lot more flexibility to move things around once you have 4-8 empty stows.

 

[Titus K]

A series of articles detailing the new Orka-class submarines (page translated to english)
https://www-marineblad-nl.translate..._sl=nl&_x_tr_tl=en&_x_tr_hl=fr&_x_tr_pto=wapp
Most notably, the KM will move to double-crewing its submarine force.

Instead of 216 submariners spread across 4 crews of 54 for the 4 Walrus-class submarines.
The KM will shift to 6 crews of 37 submariners for it's 4 Orka-class subs (or 35-40 according to other sources) ... for a total of 222 submariners (or 210–240)

This is very similar to the French Navy’s SSN manning model (10 crews for 5 operationnal subs, with 1 sub undergoing maintenance at any given time)

 

[EmoBirb]

A series of articles detailing the new Orka-class
Instead of 216 submariners spread across 4 crews of 54 for the 4 Walrus-class submarines.
The KM will shift to 6 crews of 37 submariners for it's 4 Orka-class subs (or 35-40 according to other sources) ... for a total of 222 submariners (or 210–240)

Pretty impressive that they managed to reduce the crew size so significantly despite the substantial capability growth from the Walrus to the Orka

 

[Scott Kenny]

Most notably, the KM will move to double-crewing its submarine force.

Instead of 216 submariners spread across 4 crews of 54 for the 4 Walrus-class submarines.
The KM will shift to 6 crews of 37 submariners for it's 4 Orka-class subs (or 35-40 according to other sources) ... for a total of 222 submariners (or 210–240)

This is very similar to the French Navy’s SSN manning model (10 crews for 5 operationnal subs, with 1 sub undergoing maintenance at any given time)

6 crews for 4 boats?

That may cause issues. With two crews per boat, they each feel decent ownership of the boat, and so take good care of their boat. 3 crews for 2 boats means that crews may not feel enough ownership to keep the boats in good material condition.

The US certainly had a lot of trouble with the multiple-crew experiments on surface ships because the crews didn't feel like the ship was theirs.

Admittedly, the first experiment was pretty poorly designed. There were 3 FFG7s scheduled to be decommissioned, one after the other. The idea was that the experiment ship, the last one planned to be decommissioned, would have a relatively standard deployment, but instead of returning at the end they'd turn over the ship to the crew from a ship that had just decommissioned and do a quick refit with both crews working. Then the second crew would do a relatively standard deployment and instead of returning to the US they'd turn the ship over to a third crew. The third crew would do a relatively standard deployment and then take the ship back to the US and decommission it. One ship spending something like 18 months away from the US, with some month-long refits every 6 months. When the ship finally came back to the US, the ship was pretty much wrecked.​

​

After this experiment, the USN decided that the LCS would get two dedicated crews per ship, and operate them similarly to how the Ohio-class operates. Shorter deployments per crew, and a ~1-month refit with both crews plus a local shipyard all working together to do all the work of a normal 6-month post-deployment refit (working 2 shifts, ~16 hours a day. Yes, they really suck). It works out to just short of 400 days at sea across 2 years. ​

 

[MihoshiK]

Pretty impressive that they managed to reduce the crew size so significantly despite the substantial capability growth from the Walrus to the Orka

The base design for the Walrus class is almost 50 years old. Back then they were top-of-the-line subs, by the time they will be replaced they will have been in the water for well over 4 decades.

I'd have been seriously amazed if the design had not significantly improved.

 

[Titus K]

6 crews for 4 boats?

That may cause issues. With two crews per boat, they each feel decent ownership of the boat, and so take good care of their boat. 3 crews for 2 boats means that crews may not feel enough ownership to keep the boats in good material condition.

No, as i wrote, it's 6 crews for the 3 subs in active service / in the operational cycle

In France, for the 6 Suffren class submarines it works as follows :

• one scheduled 10 week "IE" maintenance period every year --> yard busy 50 weeks per year with 5 subs in the operational cycle
• one scheduled 18 month "ITR" Maintenance/Refit/Refueling period every 10 years --> yard busy 9 years per decade with 6 subs in the fleet

The 5 subs in the operationnal cycle are double crewed (10 crews total) and available at least 40 weeks per year (minimum 270 days according to Naval Group)
The sub undergoing 18 month ITR is not crewed.

How this would translate to a fleet of 4 SSK is hard to guess ... but long term maintenance/refit periods are still needed.

Is this different from US SSBN crewing ?

 

[Scott Kenny]

No, as i wrote, it's 6 crews for the 3 subs in active service / in the operational cycle

[...]
The sub undergoing 18 month ITR is not crewed.

How this would translate to a fleet of 4 SSK is hard to guess ... but long term maintenance/refit periods are still needed.

Is this different from US SSBN crewing ?

Yes, when a US SSBN goes into a long refit, like for the SSGN conversions, they combined the two crews and basically sent all the officers from one crew away (to schools or whatever, they're not fired). The crews do a lot of work during a refit, it's not just shipyard workers doing all the work.

This is separate from the ~month-long refits between patrols, where one crew officially is in charge of the ship and the other crew is assisting. Combined watch sections for security, but there's just flat a lot of labor hours that need to happen.

 

[H_K]

6 crews for 4 boats?

That may cause issues. With two crews per boat, they each feel decent ownership of the boat, and so take good care of their boat. 3 crews for 2 boats means that crews may not feel enough ownership to keep the boats in good material condition.

It’s 2 Red/Blue crews per operational boat. 3 subs x 2 crews = 6 operational crews. The 4th sub will be in maintenance with a skeleton crew.

Based on French SSN experience this allows each crew to get 90-100 sea days per year, and each operational sub 180-200 sea days, so a total of 540-600 sea days/year for a fleet of 4 subs.

This doesn’t count foreign port calls for resupply and crew swaps, so the actual optempo is higher and forward deployed presence is much better than can be achieved by subs with single crews that have to spend much of their time deploying to/from their home port.

Just as a point of comparison, Australia’s fleet of 6 Collins SSKs has only beat 600 sea days once (in 2018), and the RAN were so ecstatic that they called it a “world beating” performance in terms of submarine availability (the 6 Collins had a goal of “closer to 700 sea days” in 2019 but there’s no evidence this was achieved, and since then availability has tanked). Well… a fleet of 4 Orcas with 6 crews should be able to achieve the same performance most years, as opposed to once every couple of decades. And with better forward deployed presence thanks to crew swaps.

…so IMHO this news about double crewing is the single most impressive element that has come out of the Dutch Orka program so far, and likely only achievable thanks to the selection of a French design as there is very little experience outside of France with double crewing attack subs.

 

[Scott Kenny]

It’s 2 Red/Blue crews per operational boat. 3 subs x 2 crews = 6 operational crews. The 4th sub will be in maintenance with a skeleton crew.

That is a very different setup than what I am used to thinking about.

The USN keeps most of the two crews together during a long overhaul, only sending the duplicate Officers, Chiefs, and Leading Petty Officers elsewhere (schools, usually). In the case of an Ohio-class, that's a "Green Crew" of about 300 working on the boat.

 

[Titus K]

Just a nice render with a 10 meter class XLUUV and the modular DDS



Also @HK made this little sketch comparing a Scorpene and a Orka, showing the 30 weapons loadout on the latter

 

[Titus K]

The F21 Mk2 torpedo has been selected by the dutch MOD for the Orka class submarines

https://www.defensie.nl/actueel/nie...oten-direct-voorzien-van-geavanceerde-torpedo

 

[Scott Kenny]

The F21 Mk2 torpedo has been selected by the dutch MOD for the Orka class submarines

Kinda expected to go with the French FCS, but the F21 does have a pretty light warhead for a 21" torpedo. 200kg is 2/3 of a Mk48 warhead. Decent performance otherwise, 50knots and 50+km range. Just surprised me how small a warhead it has.

 

[TomS]

Kinda expected to go with the French FCS, but the F21 does have a pretty light warhead for a 21" torpedo. 200kg is 2/3 of a Mk48 warhead. Decent performance otherwise, 50knots and 50+km range. Just surprised me how small a warhead it has.

Make sure you're comparing like with like. That's 250kg (550 lbs) explosive weight. Total warhead weight is 348kg (770 lbs).

https://ndia.dtic.mil/wp-content/uploads/2018/imem/20150_Chaffois_Presentation.pdf

 

[Scott Kenny]

Make sure you're comparing like with like. That's 250kg (550 lbs) explosive weight. Total warhead weight is 348kg (770 lbs).

Okay, 250kg/550lbs is much closer to Mk48 boom.

 

[Titus K]

https://www.defensiedichtbij.nl/magazines/alle-hens/2026/editie-05/09-orka-s-in-aantocht

That is no small task. The boats of the current Walrus class are about 69 meters long. The new boats will grow to around 85 to 86 meters. As a result, the existing facilities must be adapted or replaced. “The current maintenance hall will have to be extended and a second hall must be added,” according to Roersma. “In addition, we need to look at the ship lift and other facilities. These are enormous projects that we have to integrate into the current site.”

Not only does the infrastructure change with the acquisition of the Orka submarines, but the way submariners are trained is also evolving. Within the Dutch-Belgian Operational School, Lieutenant Junior Grade Leen Klein is therefore working on new training facilities. These will play an increasingly important role. SimShip is central to this. In this future simulator and training complex for the Submarine Service, operational and technical personnel will be able to train together.


“The role of simulators will become extremely important for the Orka class,” Klein agrees. “Those simulators will essentially become our fifth boat.” This is necessary because the new dual-crew concept means submarines will spend more time at sea, with two crews alternating. As a result, the boat’s availability for training decreases. Moreover, the submarine is being built for 37 crew members, which leaves no berths available for trainees. Training on shore is therefore the only solution.

 

[Titus K]

Orka will be capable of deploying a large swimmer delivery vehicule

 

[Titus K]

RoyalIHC signs with Naval Group for the production of Orka on-board accommodation modules

https://www.royalihc.com/news/royal-ihc-and-naval-group-sign-first-order-new-orka-class-submarines