Royal Australian Navy Discussions and Updates

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hauritz

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From this particular government's perspective I can see how they would be attracted by the idea of pushing back the replacement date of the submarines by a decade. Essentially they seem happy to make decisions that allow them to hold off paying for anything for as long as they can possibly get away with it.

The cost of a Collins refurb does sound daunting however. Chopping open a hull and replacing the running gear sounds like it has the potential to be yet another disastrous chapter in the Collin's saga.
 

ASSAIL

The Bunker Group
Verified Defense Pro
The cost of a Collins refurb does sound daunting however. Chopping open a hull and replacing the running gear sounds like it has the potential to be yet another disastrous chapter in the Collin's saga
I don't share your pessimism. Australian industry is more than capable of re-powering Collins, there was absolutely no problems with the quality of the Australian welding/construction of the original boats which completed basically on time and on budget (within $40m on a multi billion dollar budget).

There will be no fundamental change to the boats hydrodynamics if generators and motors are all that are changed in the drive train and other internal updates will be made so much less complex.

Cheers
 
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gf0012-aust

Grumpy Old Man
Staff member
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From this particular government's perspective I can see how they would be attracted by the idea of pushing back the replacement date of the submarines by a decade. Essentially they seem happy to make decisions that allow them to hold off paying for anything for as long as they can possibly get away with it.

The cost of a Collins refurb does sound daunting however. Chopping open a hull and replacing the running gear sounds like it has the potential to be yet another disastrous chapter in the Collin's saga.
you do realise that the structural and design disasters (esp No 1) were not ASC and were in fact defective workmanship done by Kockums?

seriously, the constant harping on about Collins in the negative continues to show how little people know about its successes and how quickly they just accept the media doom and gloom as truth in sentencing

apart from the fact that the US and USN are heavily technically and emotionally invested in RAN subs and would be having more than a passing glance if any cut and shuts were to be done.

Having seen 2,3,4 and 5 being built, I'm pretty sure that even though its not a non trivial task, its not the snowy mountains hydro scheme in complexity either
 

hauritz

Well-Known Member
I guess a major submarine refurbishment does solve the problem of filling the gap between the end of the AWD program and start of the construction of the new submarines ... which is an issue the defence minister has bought up in the past.
 

ADMk2

Just a bloke
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I've noticed that HMAS Tobruk has had her 25mm Typhoon gun systems removed since she has come back into service.

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Without breaking Opsec, is there any reason for this apart from the cost and maintenance considerations when the weapons aren't required?

I imagine adding them back on is not a trivial task and would require some time aside, to re-install them...
 

StingrayOZ

Super Moderator
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Tobruk isn't going anywhere where shes going to need a 25mm?

I think they would have her on light duties (training, civilian emergency) until the amphibious stuff gets back onto its feet. In two/three years time things should be in much better shape, and if she can hold together until then, shes doing well, for a ship they were talking about rubbing out in the mid 90's.

Doesn't anyone know of an international review where the host nations ships have all been in drydocks?

Referb of Collins makes sense, because I don't see how a homegrown sub (or anything that is suitable) is going to be ready and in-service in a sensible time frame. They have cracked them open before haven't they? While a big job, its relatively low risk compared to rushing in a new type into service?
 

rand0m

Member
From my past experience with small ships operating helicopters, a 62 meter ship is too small to operate Seahawk sized helicopters. Maybe okay for smaller helicopters like Dolphins and Squirrels, but not Seahawks. It is my opinion to operate Seahawks one needs at least a 100 meter ship, preferably longer.

The Irish tried to operate Dolphins on a 70 meter ship and gave up the ghost in the rough and tumble North Atlantic and Irish Sea.
So is the MRV 80 is totally un-realistic in operating a Seahawk? (even if it was a possible contender for SEA 1180).

http://www.austal.com/Resources/Del...-8693-bcf8493e31cf/mrv-80-data-sheets-sml.pdf
 

the road runner

Active Member
There will be no fundamental change to the boats hydrodynamics if generators and motors are all that are changed in the drive train and other internal updates will be made so much less complex.
I assume we would be going with a Stirling AIP engine ,maybe a bit of help from Kawasaki and the Japanese if we do cut the hulls and replace drive trains?

We have great Tradesmen and project management in Australia, i think the Collins issues are that Government/defence did not realise what was needed in logistics to sustain the boats.Being that we are the only operator of Collins ,parts would not be sitting on the shelf(if a breakdown was to happen).It would not have helped that the Original engine manufacturer closed shop after Collins was made.

Think Government has learnt that and will take a holistic approach when we build our future subs?
 

t68

Well-Known Member
I assume we would be going with a Stirling AIP engine ,maybe a bit of help from Kawasaki and the Japanese if we do cut the hulls and replace drive trains?

We have great Tradesmen and project management in Australia, i think the Collins issues are that Government/defence did not realise what was needed in logistics to sustain the boats.Being that we are the only operator of Collins ,parts would not be sitting on the shelf(if a breakdown was to happen).It would not have helped that the Original engine manufacturer closed shop after Collins was made.

Think Government has learnt that and will take a holistic approach when we build our future subs?

It is my perception from GF that the AIP system is not all its cracked up to be,that's why it's still sitting on a pallet. It was evaluated and deemed not warranted. Any idea if that's has changed.
 

ASSAIL

The Bunker Group
Verified Defense Pro
They have cracked them open before haven't they? While a big job, its relatively low risk compared to rushing in a new type into service?

In a way, yes. They were built in 6 sections before being welded together.
 
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alexsa

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So is the MRV 80 is totally un-realistic in operating a Seahawk? (even if it was a possible contender for SEA 1180).

http://www.austal.com/Resources/Del...-8693-bcf8493e31cf/mrv-80-data-sheets-sml.pdf
The look good but they cannot land over a beach and have a number of limitations that come with a light weight hull. As a case in point:


1. More fragile than an equivalent steel monohull and with much less carrying capacity.
2. The 400 tonne dead weight is very small and has to cater for all fuel, stores, ammunition, crew, food and water BEFORE cargo or modules are consider. A helicopter adds a lot of weight so other caro and modules need to be displaced.
3. Deadweight is based on a 25mm Typhoon, adding the 57mm just makes things worse.
4. Speed advantage is a limited asset as max range is based on quite a low speed. As soon as you hit the go pedal range drops logarithmically.
5. Aluminium construction has structural fire protection issues. Not impossible to over come but good luck with the alloy flight deck if you are seeking commercial certification
6. Design h a s limitations in sea conditions. This is not a southern ocean patrol craft.
7. Light weight construction may result in longevity issues, particularly if operated at a high operational cycle and in rough conditions ....... Aka the ACPB
 

alexsa

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Here is a sketch of what a relatively small patrol boat (though much larger than the Armidale class) with a helicopter pad might look like

esmerelda_4 | Flickr - Photo Sharing!
I was going to refrain from comment but it got the better of me. You simply cannot add a whole lot of structure and a dynamic load (like an 11 tonne helicopter) to a small platform ........ Well above the CoG, without considering stability issues and the pact of increased hull immersion. I would suggest your proposal would be compromised on this basis.


If you add a lot of weight up high to the point the centre of buoyancy cannot counteract the downward force of the CoG the you could end up with a capsizing moment which would result in an angle of loll (with the ship flopping about) or a roll over. Remember that stack fuel tanks add to the fun wit free surface moments.


When proposing adding stuff to ships weight, immersion and CoG are critical issues
 

Sea Toby

New Member
So is the MRV 80 is totally un-realistic in operating a Seahawk? (even if it was a possible contender for SEA 1180).

http://www.austal.com/Resources/Del...-8693-bcf8493e31cf/mrv-80-data-sheets-sml.pdf
I believe at the time Australia was considering the OPV they were also planning to use Seasprite helicopters. Seasprite helicopters are about half the weight of a Seahawk. While New Zealand operates Seasprite helicopters from their 80 meter OPVs, they don't operate Seahawks. Just like there is a difference in stability between a 100 meter ship to a 80 meter ship, there is a difference in stability between a 80 meter ship to a 60 meter ship too.

With the New Zealand specs, the OPVs are capable of sailing safely in SeaState 8 but the usage of a Seasprite is limited to SeaState 5, or something like that. There are times in rough and tumble seas that the USCG does not operate helicopters on cutters which carry them.
 
I take your point, and dont disagree

What I was trying to convey, but did so badly (my fault), was that with a large flight deck it might handle an SH-60 on a very rare occurence, maybe when conditions are mild and just to drop off some equipment in an emergency , or pick up a injured person

A large helicopter for such a vessel as a permanent thing is daft (my fault for not explaining this better

A much more suitable aircraft might be a Daupin as suggested (even more so if they were on OPVs - thus no need to introduce a new heli type), or alternatively an unmanned thing like a schiebel camcopter or alternatively a Firescout
 

hairyman

Active Member
Why dont we just start building the new subs when the AWD work runs out in 2019. If we have built 2 or 3 before the Collins is de-commissioned, we have increased the size of our submarine fleet earlier. This cant be a bad thing can it?
 

hauritz

Well-Known Member
We haven't got anything to build.

The only way we could conceivably start building something that soon is if we went completely off the shelf ... and there isn't really anything out there that fully meets our requirements. I guess option two might be to build more Collin's subs with new engines and other improvements.
 

OpinionNoted

Banned Member
We haven't got anything to build.

The only way we could conceivably start building something that soon is if we went completely off the shelf ... and there isn't really anything out there that fully meets our requirements. I guess option two might be to build more Collin's subs with new engines and other improvements.
Then thats something to build.
 

hauritz

Well-Known Member
Then thats something to build.
I said might ... for a submarine build project to start up around 2018/19 we would probably have to be a lot further along then we are at the moment. While an "evolved" Collins sub has been mentioned as a possibility it will certainly involve a lot more than just sticking a new engine in the the current design.

The only real chance of building a new sub based on the Collins, in a very short time frame, would be to make minimal changes to the current design ... which wouldn't match up with the requirements.
 
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