Why do more navies not use Stirling engines if they work well for submarines?
Short answerThey are effective in a specialized role, but the training, maintenance, and startup costs make adoption difficult for fleets without an established support base.
NotesThe Swedish submarine installation is identified as Stirling-engine air-independent propulsion operating alongside diesels. Its application is described as specialised. Maintenance demands and the need for highly proficient personnel make the initial transition difficult. Once the support arrangements and skills exist, the system is considered useful, but a new operator must first bear the cost of establishing them.