Aluminium and steel fatigue differently. Aircraft also are closer to the minimum due to the need of being light enough to take off. Subs are incredibly heavy for their size. Aircraft have large wings that need to support their entire mass, subs, body lift, they are supported everywhere.
Collins weren't just laid up for a while, but also had limited depth usage, particularly after an accident nearly sunk one and limited them more than their design spec. They have had a particularly light duty life as a structure, and they are a well built structure. RAN CONOP doesn't see them going to maximum safe diving depth.
Toss those engines fit the MTU units, re-battery, re-sensor, and I would go further, I would pretty much gut the whole things. I would lengthen them, I would fit VLS outside of the pressure vessel at the nose like the Virginias. If we are going to be stuck with them until mid 2040, lets do them right.
As for making them in the UK.
There are limits to what can be built and where. They now need to squeeze in the building of multiple SSBN at ~17500t each, more than twice the size of the Astute.
While there may be some months where you could weld something up in the hall, it will have to be shifted, and shifted somewhere else entirely. Ideal for a hot start of our production, perhaps a bow section. Perhaps as much as a 1/3 of a boat, but there would be issues beyond that. The Astutes aren't simple boats. Look at that alien profile and chines. The Americans are pipes in comparison.
Ok guys, probably a silly question but here goes. If the systems and reactor are the same, what apart from manning and boat type maintenance, would be the issues of operating 4x Astutes and 4x Virginias? I'm just thinking if we want boats in the water asap, we could have the first of each type constructed in their respective countries simultaneously while we gear up here for local builds....
I would say impossible. That would mean the RAN would have to crew three different types of boats at the same time. The Americans are even more build restricted than the poms. They are putting everything they can into trying to accelerate their sub program, which has suffered some delays.
Maintaining a two-per-year Virginia-class build-rate will help the Navy reach its goal of 66 attack submarines, a Navy spokeswoman said.
www.businessinsider.com
The current or previous status quo had been for the Navy to drop from building two Virginia-Class boats per year to one in the early 2020s when construction of the new Columbia-Class nuclear armed submarines begins.
The completed study, however, maintains that the Navy and industry can produce two Virginia-Class boats and one Columbia-Class submarine per year, increasing the current plan by one Virginia-Class boat per year.
So yeh, they are squeezing their suppliers to get 50% more capacity from them, annually. While the US will help with technology, training, systems etc, they want Australia to start bloody making submarines. They don't have any time dicking around.
But rather than a tense relationship through a single French prime, we now have the backing of essentially the US and UK governments.
We need to start building submarines likes its 1939. Like our sovereignty, like the world order, like our lives depend on it.
