Diesel-electric. They cruise around just under the surface on diesel, with snorkels to bring in air and expel exhaust. But, then they can shut down those diesel engines, fully submerge, and maneuver on batteries for a few days and maybe a hundred miles.
While they are on diesel engines, they are loud, and stuck to the surface. While they are on batteries, they are silent. For the few days that they are submerged, they are quieter than our nuclear subs.
Yeah, they pose a potential threat to a carrier group, but the “proportional response” to attacking a carrier would be the destruction of every naval facility they have, so not exactly a serious threat.
I don’t know anything about Iran’s subs, but Sweden’s famously stealthy diesel subs keep a big tank of liquid oxygen on board and mix the exhaust with seawater before releasing it
Diesel subs use snorkles when using their engines and batteries for silent running. They work a lot like diesel/electric trains, in that the diesel engine is acting more like a generator for an electrical engine.
How does a diesel sub get the oxygen to function? And where does the exhaust go?
Diesel-electric. They cruise around just under the surface on diesel, with snorkels to bring in air and expel exhaust. But, then they can shut down those diesel engines, fully submerge, and maneuver on batteries for a few days and maybe a hundred miles.
While they are on diesel engines, they are loud, and stuck to the surface. While they are on batteries, they are silent. For the few days that they are submerged, they are quieter than our nuclear subs.
Yeah, they pose a potential threat to a carrier group, but the “proportional response” to attacking a carrier would be the destruction of every naval facility they have, so not exactly a serious threat.
I don’t know anything about Iran’s subs, but Sweden’s famously stealthy diesel subs keep a big tank of liquid oxygen on board and mix the exhaust with seawater before releasing it
Diesel subs use snorkles when using their engines and batteries for silent running. They work a lot like diesel/electric trains, in that the diesel engine is acting more like a generator for an electrical engine.
IIRC from my C:MO experience, diesel subs (at least Greek ones that is) only use diesel above surface, and use batteries when submerged