Hi tomw

I agree the SEA 1000 project has less pragmatism than many projects. SEA 1000's official parameters eg. must be conventional, Australian built, built in/near Adelaide, suggests priorities other than lowest price or sheer military efficiency.

The official parameters do suggest that Federal money for South Australia for manufacturing industry development, business, union and electoral interests are prime considerations. With an SEA 1000 in-service deadline of around 2035 we may well continue to have this discussion for the next 5 years :)

Leaving aside the most capable sub in the shape of 4 to 6 Virginia SSNs, there appears to be 4 or 5 conventional choices.

HDW (Type 214 or 216?) and DCNS (Scorpene?) being the firms with the greatest export experience and deepest knowledge base in conventional subs appear to be, or should be, the front-runners. Inter-operability with the US is important hence its is highly desirable that these firms would be permitted by the US to incorporate the US combat system and weapons fit.

The Navantia S-80 apparently incorporate the US combat system-weapons fit. However the S-80 falls down in not being completed, not exported. The S-80 has been significantly delayed due to basic design faults including balance. Navantia (or Spain?) apparently has never completed a submarine by itself or exported a sub itself. As things stand this may make Navantia a higher risk sub maker than Kockums was in the 1980s?

Note in the 1980s Kockums was chosen over the more proven HDW at the last minute - and the rest is history. Now we have never completed a sub Navantia.

If Defence-DMO-Navy wish to choose Navantia for the wrong bureaucratic high risk-problematic reasons then Navantia instead of HDW or DCNS might make sense.

Other builders are South Korea building HDW designed subs and Japan's Soryu class - though noting Japan has never exported large weapon systems, peace constitution and highly changeable government policies.

If Navantia develops a demonstrably efficient S-80 and gets some export orders for subs experience before 2025 then it might be less high risk and less expensive.

Regards

Pete