My favorite Norwegian War Ships. It is small and has good seakeeping. But lacking a bit of speed (22 knots), thanks to a government they had in the 60's that want to save money. the boat was originally designed around 10 meters longer than when it was built. which gave a speed lost around 5-7 knots! otherwise a small - large ships.
It had its weaknesses, especially against air attacks, but it was a dangerous against U-boat, when it was build. But the Oslo class took over the that, when they got an upgrade that Sleipner did not get!
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Sleipner class.png