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Swedish Gotland sunk American nuclear powered submarines!

An SSN has advantage of high transit speed, compared to SSK. So, similar to a superior fighter, it can choose to brake of and leave an engagement. But, .... at high speed, sonar performance is much degraded, leaving the boat essentially near blind (applies to surface ships too).

It is balony AIP equipped boats are limited to 4-5 knot speeds.
E.g. Singapore's Archer AIP equipped class: "The AIP system offers vibration-free and silent operation, while extending the submerged endurance from days to weeks. The propulsion system provides a surfaced speed of 8kt and submerged speed of 15kt. "
Archer Class Submarines - Naval Technology
E.g. Japan's Soryu class
"Soryu is powered by a diesel-electric propulsion system. Two Kawasaki 12V 25/25 SB-type diesel engines and four Kawasaki Kockums V4-275R Stirling engines provide a total power output of 2,900kW surfaced and 6,000kW submerged. Soryu is the first submarine of the JMSDF to be equipped with Stirling engines manufactured by Sweden-based Kockums. Stirling is a silent and vibration-free external combustion engine. The Kockums Stirling air independent propulsion system onboard reduces the need for frequent battery charging surfaced and thus increases the submerged endurance of the submarine. The propulsion system provides a maximum speed of 20kt."
SS Soryu Class Submarines - Naval Technology
These are maximum speeds not AIP speeds.

Soryu has 6,000 kW electric engine which provides 20 knot speed.
But Soryu's AIP engine is only 300 kW (4x75). This can provide no more than 4-5 knots.
 
These are maximum speeds not AIP speeds.

Soryu has 6,000 kW electric engine which provides 20 knot speed.
But Soryu's AIP engine is only 300 kW (4x75). This can provide no more than 4-5 knots.

I think that depends on the type of AIP employed:
Closed-cycle diesel engines, generally with stored liquid oxygen (LOX)
Closed-cycle steam turbines
Stirling-cycle heat engines with external combustion
Hydrogen-oxygen fuel cells

The first full-scale undersea application of closed-cycle steam turbines will be in Pakistan's three new Agosta 90B submarines, which will each be fitted with a 200 kilowatt MESMA system for increasing submerged endurance by a factor of three to five at a speed of 4 knots.

Sterling engines, however, burn liquid oxygen and diesel fuel to generate electricity for either propulsion or charging batteries within a conventional diesel-electric plant. The resulting underwater endurance of the 1,500-ton boats is reported to be up to 14 days at five knots, but significant burst speeds are possible when the batteries are topped up.

PEM fuel-cell modules on U212A: With metal-hydride hydrogen storage, the system is predicted to yield 14 days submerged endurance and the ability to run up to eight knots on the fuel cells alone.

See AIR-INDEPENDENT PROPULSION – AIP Technology Creates a New Undersea Threat
The AIP Alternative
 
American war industry has not evolved since the end of cold war so its really a credit of old tech under use by americans.
 
I think that depends on the type of AIP employed:
Closed-cycle diesel engines, generally with stored liquid oxygen (LOX)
Closed-cycle steam turbines
Stirling-cycle heat engines with external combustion
Hydrogen-oxygen fuel cells
All AIPs have very little power:

Stirling - 2x75 or 4x75 kW
Fuel Cell - 2x120 kW
MESMA - 200 kW

American war industry has not evolved since the end of cold war so its really a credit of old tech under use by americans.
What are u talking about? Virginia and Seawolf are most powerful subs today.
 
All AIPs have very little power:

Stirling - 2x75 or 4x75 kW
Fuel Cell - 2x120 kW
MESMA - 200 kW


What are u talking about? Virginia and Seawolf are most powerful subs today.

Still not in mass deployment even though technologically advanced in tech.
The Gotland is based on Stirling engine which needs on-board liquefied oxygen storage - a massive risk.
 

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