Drive system independent of the outside air

Air-independent propulsion (ger .: air-independent propulsion , shortly AIP ) is a generic term, including submarine actuators include that neither conventional ( diesel-electric ) nor nuclear are. While diesel-electric submarines rely on fresh air to operate their diesel generator, nuclear submarines are also independent of the outside air.

Submarine drives that are independent of the outside air are characterized by the fact that they can propel a submarine for longer than 30 days without the supply of outside air.

Examples of air-independent, non-nuclear drives:

• Walter drive
• Circulatory drive
• Fuel cell drive (mostly in combination with a diesel-electric propulsion system, e.g. in submarine class 212 and the Spanish S-80 class )
• Stirling engine (implemented in the Swedish Gotland class and the Japanese Sōryū class , planned for the Australian Collins class )
• MESMA propulsion (used on Pakistani submarines of the French Agosta class ; intended for the French / Spanish export submarines of the Scorpène class .)