S-80 Plus an Orphan Sub

Following this article Locum provided interesting comments on February 9, 2021, to which I respond:

On Spain's/Navantia’s S-80 Plus. (4 being built for the Spanish Navy)

Hi Locum

I assume you are saying the Dutch knocked back the S-80 Plus “in December 2019.” on cost grounds. Also the major displacement/buoyancy error of the original S-80 would have worried the Dutch.

Australia had/has good relations with Navantia during the Hobart-class and Canberra-class builds, but Navantia's grievous error in the original S-80 design was unacceptable for Australia. In that regard keyword “S-80” came up often in anonymous Australian searches - up to 2013. It seemed the usefully large S-80 design was a strong possibility to be shortlisted by Australia – but by then Spain’s dreaded buoyancy mistake was discovered . 

Root of the Buoyancy Problem

In addition to your “original S-80 there was no spare room for drones or extra SOF / commando's, over the standard 8 SOF operators.” There were other Combat System weights (eg. torpedos, tubes, missiles, servers and workstations). These essential weights were not factored in by Spain when Spain did its buoyancy calculations.

I’ve said somewhere that Spain had never fully developed and launched a sub in Modern times without major French help. Probably it was this Spanish inexperience that resulted in the failed S-80 design.

Now since 2019

The Dutch would have noticed that the S-80 Plus design for the Spanish Navy, "3,200 tonnes (surfaced) and 3,426 tonnes (submerged)" see right side bar, has little reserve buoyancy and is too heavy for the Dutch Navy overall.

As you point out, an additional problem is the S-80 Plus “engine room is too cramped for...3 MTU 396s” that the Dutch Navy probably wants. Although I'd say the Dutch economic ministries may be happy with only 2 diesels in much cheaper MOTS European designs.

Like the Australian Collins and now Attack classes, the Spanish have created an extremely expensive orphan submarine class in the S-80 Plus. 

Collins, Attack and S-80 Plus are only attractive to their builder shipyards-navies with no export prospects to amortize individual sub and project cost burdens. Any Australian hopes that the Dutch would look to Australian Attack class builders will pan out to be the Dutch going to Naval Group directly.