This is why I brought up AIR-6000 – which you ignored: VLO was not a fundamental requirement for the tender process. It is essentially an additional technological capability the F-35A provides the ADF, which can be leveraged to produce those enhanced tactical, operational and thus strategic outcomes. ADF doctrine in the mid-2000s literally had nothing to do with it – doctrine is plastic to technological developments. What this means is your whole conception of doctrine is completely backwards. Any user of a new platform will not simply state a list of things it wants a new platform to do for the next 20 years and ignore any additional technological advantage the platform provides – write a concept of operations document and then ignore the platform’s actual capability. That idea is just plain silly. There are a million historical examples: Look at the relationship between the second offset and AirLand battle if you don’t like the Germans.
I deliberately ignored AIR6000, because IMO that is an apples to oranges comparison. There are features included in the F-35 variants because other F-35 programme partners wanted them. The AIR6000 programme might not have had LO or VLO as a capability requirement, but look at the existing and pending new fighter aircraft programmes around the world. Which programmes can/will meet the RAAF requirements for now and into the future? What will the initial acquisition and ongoing operational/support costs be? What about future developments and upgrades? Etc. etc. In the case of the F-35 programme, other features required by other customers lead to the RAAF selection having additional capabilities (requiring new CONOPS be developed to properly utilize them) not initially part of AIR6000. In the case of SEA1000, this is a development programme for a sub for the RAN. The final design might have capabilities of interest to a few other conventional sub operators whom Australia might be willing to share with (Canada and perhaps Norway), but why would Australia pay for the development of design capabilities which do not fit with how the RAN operates subs now, or expects to in the future?
Now, pugachev's cobra, that old chestnut. This gets to the heart of the matter: if an additional capability a certain technology provides cannot be reasonably leveraged to achieve those achieve tactical, operational and strategic outcomes, doctrine will essentially ignore it. I completely agree. However, IF DCNS is able to provide a transit speed of 14 knots, is it equivalent to pugachev's cobra, only useful at air shows??? If you believe that, then you need to be introduced to the concept of operational – and potentially strategic – mobility.
The unanswered elephant of a question in the room, is whether or not a 14 kts sustained transit speed for the future sub is worth the presumably extra power cost to achieve, from the perspective of the RAN. Now if the RAN has a choice of say, 8 kts sustained transit, or 14 kts sustained transit, both for the same duration, radiating noise, and level of power consumption, then a 14 kts sustained transit would clearly be a better choice IMO. However, the suggestion has been made earlier in this thread that the energy consumption for doubling the propulsion speed cubes the rate of energy consumption. I will touch on this further in the point below.
I’m not sure I even want to touch this. Apart from the earbashing people have had from mods in this thread regarding making claims about performance of a submarine which hasn’t even had the power plant selected – I’m not sure how that level of analysis is allowed to go unchecked – you have made no account for improved energy density improvements or AIP (seems like you have just attacked a pump jet to a Collins) not to mention the confusion of operational and tactical mobility and a totally unsupported tactical picture. Seriously, if people have an issue with DCNS making claims about Shorftin Barracuda capability I don’t know what to do with this level of speculation.
Actually, I have not. The impression I have gotten (again, not a marine engineer) is that from a power consumption perspective, a pumpjet is not as energy efficient as a conventional prop. Which means the very rough, back of a napkin calculations I did would be even less accurate. If the formula of double the speed, cube the power requirement is correct, then to run a
Collins-class sub at 16 kts for one hour should consume approximately the same amount of power as a
Collins-class sub would, transiting at 4 kts for 64 hours, excluding the base/hotel load.
The point I have been attempting to raise and get across, is that without some commentary from the RAN, we have no way of knowing whether or not the RAN subs would operated at sustained transit speeds of 14 kts. We do not know what else the RAN wants or needs to do with the power which will be available aboard the future sub. If everything else (and I mean, everything) is the same, then a higher transit speed would be advantageous. However, at some point, range/persistence become more important than sustained speed. Lacking either a time or distance factor for the sustained 14 kts, and/or what other implications sustaining such a speed would have means that it's relative value is unknown.
The
ANZAC-class FFH can be looked at as an example, with a published range of 6,000 n miles @18 kts, and a max speed listed at 27 kts. I would suspect that a speed higher than 18 kts can be sustained by an FFH, however I would also expect that the rate of fuel consumption would increase greater than the speed. No idea if the numbers are accurate (and not important since this is just to illustrate what I mean) but a sustained speed of perhaps 20 kts might decrease the range down to 5,000 n miles for instance.
Maybe, maybe not. But the wider point isn’t “yay DCNS’: there is much more to all of this than simply who’s widget is better or whop seems to be the more reliable partner. The geostrategic impactions of SEA 1000 are hardly insignificant, neither is the impact on Australian industry or wider defence capability. These issues are every bit as important as the design of the boat or where it comes from.
Yes, but these elements are also independent of the design of the boat or it's origin. The Oz industrial and defence impact from SEA1000 would occur no matter what, as long as SEA1000 actually occurs.
Please note, when I have used a formula or listed a published or calculated speed, I freely admit I do not know the exact, accurate number. In fact, for the publicly available numbers, I strongly suspect they are deliberately inaccurate. Due to the points I have been attempting to make, the specific number values are less important than consideration for how changing one number would impact other numbers.