Royal Australian Navy Discussions and Updates 2.0

Stampede

Well-Known Member
Just wondering if we have sold off NUSHIP Arafura as there has been little info since it was dropped in the water Dec 2021.
I think it's now 2023!

Not talking up-gunning or the Defence Strategic Review.

Is it in the water doing stuff.
Has it's rubber band broken?

Have not seen a Pic more recent than 2021

Just curious.


Cheers S
 

Tbone

New Member
Good question.., the trail has gone cold!
There would have to be 2 or 3 OPV’s basically completed or fitted out by now!

possibly they are being re fitted or modified for the MCM role instead?

that would be my only conclusion so the baby can start on a better vessel for the upheaval ahead.
 

ADMk2

Just a bloke
Staff member
Verified Defense Pro
Good question.., the trail has gone cold!
There would have to be 2 or 3 OPV’s basically completed or fitted out by now!

possibly they are being re fitted or modified for the MCM role instead?

that would be my only conclusion so the baby can start on a better vessel for the upheaval ahead.
Certification issues are holding up sea trials on the class is my understanding, for a variety of reasons…

As they’ve already commenced building number 6, we’re a long way into the program… The calls for termination and so on are rather late.
 

hauritz

Well-Known Member
I have a suspicion that all will be revealed in the up coming defence review. The Armidales are on borrowed time. There are eight remaining in service and I expect they will go sooner rather than later. The navy currently has 5 Cape class PBs with another 5 under construction.

That would give the navy 10 Cape class PBs. That would seem to be a lot of interim patrol boats. Feel free to speculate why the navy would fast track interim replacements for the Armidales when production of the Arafura's is in full swing.
 

spoz

The Bunker Group
Verified Defense Pro
Of the two building in SA, Arafura is fitting out and Eyre has yet to be launched. None of the four presently building in the West has been launched. It is common for the first of class to precede others by some time; it enables the bugs to be worked out.

What I don’t understand about the Capes is why they are not being commissioned; why continue with the “ADV” thing when they are full time Navy, manned by Navy crews? Why not “HMAS”?
 

ddxx

Well-Known Member
What I don’t understand about the Capes is why they are not being commissioned; why continue with the “ADV” thing when they are full time Navy, manned by Navy crews? Why not “HMAS”?
I’ve been wondering about the exact same thing. ADV is usually only used for ‘Auxiliaries’ with either partial or full civilian crews?

I also find the term “Boat” for a ~60 metre vessel somewhat unfitting. Wouldn’t “Patrol Vessel” make more sense?

It would be good if the DSR includes a proper rethink in how we structure our patrol assets. The current set up seems unnecessarily messy.
 

Stampede

Well-Known Member
Of the two building in SA, Arafura is fitting out and Eyre has yet to be launched. None of the four presently building in the West has been launched. It is common for the first of class to precede others by some time; it enables the bugs to be worked out.

What I don’t understand about the Capes is why they are not being commissioned; why continue with the “ADV” thing when they are full time Navy, manned by Navy crews? Why not “HMAS”?
I don't want to read to much into it all, but I am surprised how little news there is since Arufura's launch Dec 2021.
Yes the class is well into production so would be surprised if the 12 vessels are not built.
As to how they are employed time will tell.
The Boarder Force / Navy thing.
Both operating similar vessels and the naming prefix? ..................Just clunky and weird.
This realm needs clarity and I'd guess some efficiency.
Others better qualified could advise.

Cheers S
 

hauritz

Well-Known Member
Regardless of the rumoured corvettes the RAN needs the Arafuras. I don’t know how long it would take to build a new class of warship but the navy needs to replace its patrol boats long before these new ships become available.
I am also not sure the navy would have the manpower to operate both ship types long term.
 

ddxx

Well-Known Member
I am also not sure the navy would have the manpower to operate both ship types long term.
If we look at total personal as a percentage of total population, it’s worth remembering that by the time even HMAS Hunter is commissioned, Australia’s population would have grown by over four million compared to today.

I agree that Arafura has an important place in Maritime Security for our EEZs. They’re perfect for that role, but they do need a decent gun capable of dealing with the rise of more militant style illegal fishing.

If we want a second tier combatant between Arafura and Hunter/Hobart, Corvettes or loaded up OPVs aren’t the way to go about it.
 
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Stampede

Well-Known Member
I don't want to read to much into it all, but I am surprised how little news there is since Arufura's launch Dec 2021.
Yes the class is well into production so would be surprised if the 12 vessels are not built.
As to how they are employed time will tell.
The Boarder Force / Navy thing.
Both operating similar vessels and the naming prefix? ..................Just clunky and weird.
This realm needs clarity and I'd guess some efficiency.
Others better qualified could advise.

Cheers S
Quoting my own post, but just came across this today in APDR re the Arafura Class and Luerssen Australia.




Looks like they are here for a while building stuff.

Cheers S
 
I bow to others knowledge of naval systems but I’d like to back this up and comment on the general unfeasibility of replacing a crewed SSN or SSK completely with a solely battery-electric SS (SSE?) or AUV. The physics simply doesn’t stack up.

The Collins/Attack/AUKUS saga has highlighted that range is a critical factor for RAN subs. To get range a sub needs to be powered either by something where the fuel doesn’t run out (nuclear) or carries enough fuel to burn to provide the required amount of energy needed to reach the range provided (Diesel) or stores the energy directly (battery). In all three cases the sub also needs to contain the crew, weapons, sensors and the engines that will take that energy and convert it to forward movement.

So the rate at which energy can be stored is critical. The more dense the form of energy storage, the further the sub can go for a given fuel storage space. The following are theoretical maximum energy storage density in Mega Joules (MJ) per litre of volume for various sub power options:
Lead battery 0.5 MJ/L
Lithium battery 4.3 MJ/L
diesel fuel 45 MJ/L
Uranium U235 3,900,000 MJ/L

Clearly, even the most efficient battery is ten times less efficient in energy storage than diesel fuel. Nuclear power is one million times more efficient. There is simply no way a submarine or UAV powered by battery alone will travel as far, or as fast, or carry as much as a similar sized SSK, let alone SSN. Some things engineering and research can resolve over time. But not basic physics.
I have written many words off forum to Alexa. Perhaps he is yet to read. I was doing the maths. I will try and summarise very briefly.. a drone sub can be large, 1000t 2000t or 3000t. Because no crew is carried. Much space and weight is freed up. Because no crew is carried, the use of very slight risky lithium Ion batteries is permitted. Mass fraction of batteries in Collins class is under 12 percent. If crew, crew spaces. Galley, air conditioning etc are all removed the sub becomes much simpler. A plausible mass fraction for batteries might be 36 percent. Li ion batteries are 280 watt hour per kilo or 7 times that of lead acid. Thus with three times larger mass fraction and 7 times larger energy density things improve a lot... But still not quite enough., Thus a two part system is required, either a towed battery pack or a tug that tows the robo attack sub underwater I did the calcs a 3400t drone tug could tow a 2000t drone attack sub 4800 miles at 4 Knots to an area and then back again with reserve. Because the towing sub is unarmed mass fraction of batteries could be very high say 50 percent or 1700t... I can provide the maths off forum if you like, just message me... Aside is there a more appropriate forum for ideas like this, after a quick look could not find
 
Was not aware of that. Is cool. Using Li ion batteries and long range only works with very high battery mass fraction and large size.. fuel cell permits smaller size and long range.. really needs a thread away from here..
 

Scott Elaurant

Well-Known Member
"Ghost Shark" is a program for a range of xluuv,s to be developed in Australia was this what you were considering?
Australia's Future XLUUV Named 'Ghost Shark' - Naval News
And there is this
Fuel Cell Powered XLUUV for Royal Australian Navy - Defense Advancement
Seaspear

Thanks for highlighting the Ghost Shark. To me its dimensions lend itself perfectly to being operated as a capability that can be deployed from a dry deck shelter (DDS) on a future RAN SSN. The SSN will have ample spare power to charge, launch and potentially recover and recharge a UAV.

In effect our SSNs could act as “motherships” to these UAVs. This would allow them to perform dangerous tasks such as Active Sonar searches in ASW, with the crewed SSN one step removed and out of harms way.

I note the DDS already fitted on US SSNs is 12 metres long x 2.7 m diameter. This makes it a very close match to the Ghost Shark, which is 12 m long and 1.7m diameter. The UK Chalfont DDS on Astutes looks similar.

The 5000km range of Ghost Shark is impressive and could allow its independent use for coastal missions. but that is still a long way short of what is needed to reach critical choke points north of Australia, patrol, and return. So I still think deployment of a UAV from an SSN makes the most sense.
 

Volkodav

The Bunker Group
Verified Defense Pro
I have written many words off forum to Alexa. Perhaps he is yet to read. I was doing the maths. I will try and summarise very briefly.. a drone sub can be large, 1000t 2000t or 3000t. Because no crew is carried. Much space and weight is freed up. Because no crew is carried, the use of very slight risky lithium Ion batteries is permitted. Mass fraction of batteries in Collins class is under 12 percent. If crew, crew spaces. Galley, air conditioning etc are all removed the sub becomes much simpler. A plausible mass fraction for batteries might be 36 percent. Li ion batteries are 280 watt hour per kilo or 7 times that of lead acid. Thus with three times larger mass fraction and 7 times larger energy density things improve a lot... But still not quite enough., Thus a two part system is required, either a towed battery pack or a tug that tows the robo attack sub underwater I did the calcs a 3400t drone tug could tow a 2000t drone attack sub 4800 miles at 4 Knots to an area and then back again with reserve. Because the towing sub is unarmed mass fraction of batteries could be very high say 50 percent or 1700t... I can provide the maths off forum if you like, just message me... Aside is there a more appropriate forum for ideas like this, after a quick look could not find
What about battery cooling? Not only that, cooling for various systems from propulsion to combat systems.

The various layers of cooling in current submarines is maintenance intensive (as is propulsion). A big reason the subs have crews is to ensure the systems that get the combat system to where it it needed work.
 

ddxx

Well-Known Member
Thanks for highlighting the Ghost Shark. To me its dimensions lend itself perfectly to being operated as a capability that can be deployed from a dry deck shelter (DDS) on a future RAN SSN
The media release on this made for some confusing articles.
The UUV pictured and described in the article is the small testing platform called 'Dive-LD".

The actual Ghost Shark will be an XLUUV described as being about the size of a bus.

I'd imagine an OSV might be a suitable platform, by utilising the large deck space and native crane.
 

Reptilia

Member
Seaspear

Thanks for highlighting the Ghost Shark. To me its dimensions lend itself perfectly to being operated as a capability that can be deployed from a dry deck shelter (DDS) on a future RAN SSN. The SSN will have ample spare power to charge, launch and potentially recover and recharge a UAV.

In effect our SSNs could act as “motherships” to these UAVs. This would allow them to perform dangerous tasks such as Active Sonar searches in ASW, with the crewed SSN one step removed and out of harms way.

I note the DDS already fitted on US SSNs is 12 metres long x 2.7 m diameter. This makes it a very close match to the Ghost Shark, which is 12 m long and 1.7m diameter. The UK Chalfont DDS on Astutes looks similar.

The 5000km range of Ghost Shark is impressive and could allow its independent use for coastal missions. but that is still a long way short of what is needed to reach critical choke points north of Australia, patrol, and return. So I still think deployment of a UAV from an SSN makes the most sense.

forward deployed undersea docking stations are already on the cards for uuvs.

11.35 to 14.49
 

Morgo

Well-Known Member
Interesting story about resistance from the US to Austal being involved in any AUKUS sub build. Whatever they did must be pretty bad…. looks like the accusation is that they were selling designs and technology for the Independence LCS to the Chinese:

AUKUS jitters: Congressman wants Austal blocked from submarine deal

Presumably any contribution by Austal to an AUKUS submarine would have been pretty minor anyway. I wouldn’t have thought they’d have a reason to be involved at all.
 
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