Royal Australian Navy Discussions and Updates

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ThePuss

Defense Professional
Verified Defense Pro
If the book referred to several posts back ("The Collins Story...") is to be believed, the Hedemora engines were chosen because they were narrow and the required two main engines could be sited side-by-side and reducing the length of the machinery spaces.
The MTU diesels by contrast were wider and could not be sited side-by-side. If fitted they would have had to be sited consecutively, and would result in a lengthening of the hull.
A Collins 2 hull of 9.6m diameter might enable side-by-side MTUs again.

To be fair to the choice (and hindsight is always valuable), the Hedemora diesels seemed to be fine in two classes of Swedish submarines, at least from public information in English. From the outside, it seems that the significantly larger Collins (more drag and higher power requirements) was operationally harder (long transits at higher speeds) on the drive-train than the more leisurely Baltic/coastal duties.
I do note that the latest Swedish subs have MTU diesels.

GF: I'm quoting you for the comment, not necessarily directing reply at you.
Im not trying to nit pick here...well maybe i am :p but the Colins are powered by three Hedemora diesels .

I don't want to be accused of using Wikipedia, so here it is on the navy own site

HMAS Collins - Royal Australian Navy
 
No, fair enough! I should have taken the 2 minutes to double check that before posting. You know what assuming makes me...

It has been some years since I read the book, and I'm now wary enough at my carelessness to wonder if I didn't misapply the side-by-side rationale regarding the Hedemora engines. Am I at least right about that?

I have the book as well.
I've also worked inside numbers 2,3,4 and worked on 5
I know how wide they are :)
Just for my own knowledge, and from the parts you have experience of (I don't need to know specifics), would you say the book is a fair representation of what happened? If it doesn't violate forum rules, even a careful, single word answer would be appreciated. :)

I think it is difficult to tell from the outside, what with conflicting agendas(*) dueling with the narrative. From my reading it seemed that while the authors were...I want to say "sympathetic"...to the project, they didn't ignore criticism or fail to address alternative views and opinions. That made it a good read.

* = Labor/Liberal, Defence/media, Navy/other services, Navy clique/Navy clique, etc.
 

ThePuss

Defense Professional
Verified Defense Pro
No, fair enough! I should have taken the 2 minutes to double check that before posting. You know what assuming makes me...

It has been some years since I read the book, and I'm now wary enough at my carelessness to wonder if I didn't misapply the side-by-side rationale regarding the Hedemora engines. Am I at least right about that?
.
We all make the occasional gaff mate ,most defiantly me included :D. Yes the Donks are three abreast. Maybe the book mentions that only 2 MTU's could be fitted instead of 3 Hedemora's? Cheers
 

ADMk2

Just a bloke
Staff member
Verified Defense Pro
What about quoting the public domain source? E.g. linking to a newspaper article. You're not saying "this is so", only that someone else says it is.
The stats for an F-88 Steyr rifle have been around for donkeys year in the public environment, but that tabulated data for it is still classified as restricted within Army...

Anyone can find out about it, but Army info like that can't be revealed publicly by just anyone...
 

gf0012-aust

Grumpy Old Man
Staff member
Verified Defense Pro
What about quoting the public domain source? E.g. linking to a newspaper article. You're not saying "this is so", only that someone else says it is.
if you referenced a public domain article you'd be fine. they get a bit twitchy if they see shop talk.

eg there is public domain janes info and then there is the govt scrubbed versions of janes that are only made avail to govt and can't be bought except through govt accounts. if janes gov generated data appeared hen things would get a tad exciting.

things like absolute platform weights, performance specs, range, top speed etc are very different between the two versions.
 

StingrayOZ

Super Moderator
Staff member
Submarines have used many engines and there have been issues with lots of them. Many are based of train engines and don't work well in the enviroment of a submarine, salt water in diesel fuel, constant load then hard shut off, complicated exhaust and intakes. I believe the collins engines were adapted and supercharged as well.

The ABC series on collins seemed to highlight the operational use of the engines as being an issue. While other countries the engines might be used for a short period, then idled, then shutdown RAN seems to have a different SOP. Littorial subs won't work diesels as hard as a sub thats got to do several thousand mile transit. Which is why I kinda like the idea of a gasturbine or two in the conning tower, where if you want to operate like that you can, and if the engine destroys itself its servicable, but that brings its own issues.

People somehow think Collins is the worse submarine in the world. Then they read a story about the upholders, or pretty much any submarine.
 

jack412

Active Member
I have the book as well.
I've also worked inside numbers 2,3,4 and worked on 5
I know how wide they are :)
Back in my day, I just walked in and had a look at the collins being built, re the size, it was big.
I didn't think too much about the security issues at the time, no one challenged me and no I didnt carry a clip board or spanner, the ultimate pass :cool:
Also at one stage, they took the back panels off the shed and had the sturn of a boat sticking out for ages
 
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StingrayOZ

Super Moderator
Staff member
Speaking of collins press..

Video: Aboard a Collins class submarine

Video on a Collins. Funny enough operating off the NSW coast.

I do feel basing some of them in Sydney would help with the press, if people could clearly see them moving in and out of the harbour going to training exercises then press about them all being broken would be a much harder sell. Subs in Sydney always looks good.
 

StevoJH

The Bunker Group
Speaking of collins press..

Video: Aboard a Collins class submarine

Video on a Collins. Funny enough operating off the NSW coast.

I do feel basing some of them in Sydney would help with the press, if people could clearly see them moving in and out of the harbour going to training exercises then press about them all being broken would be a much harder sell. Subs in Sydney always looks good.
Not just the press, it would also have to affect retention.
 

l0cKd0wn-UnIt

New Member
Also just curious on something with the Collins Class -

Why is it that whenever a Collins class submarine comes out of the water, they always have the propeller covered, something secret or just to make it dry quicker? :cool:
 
Also just curious on something with the Collins Class -

Why is it that whenever a Collins class submarine comes out of the water, they always have the propeller covered, something secret or just to make it dry quicker? :cool:
It's because underneath is a genie turning it. I can't believe you asked that question.
 

Volkodav

The Bunker Group
Verified Defense Pro
A genie? I thought it was because there were tow attachments for the sub to be towed by a whale there?
Its to hide the fact there is no propeller as they rely on catapillar drives instead and the stern actually houses a lockout chamber capable of docking a Seal Delivery Vehicle.
 
Its to hide the fact there is no propeller as they rely on catapillar drives instead and the stern actually houses a lockout chamber capable of docking a Seal Delivery Vehicle.

I think you mean:

[ame="http://en.wikipedia.org/wiki/Magnetohydrodynamic_drive"]Magnetohydrodynamic drive - Wikipedia, the free encyclopedia[/ame]
 
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