HNLMS WALRUS

[Tynesider]

Passing the Dutch submarine HNLMS WALRUS 18-5=2014

[E28]

4 good images of this Dutch boat from Mike.

There are a lot of protuberances here, this is what they do...

Top - general view.
Second - Port quarter shot shows her X tail combined aft planes and rudders and protruding from each side of her fin / sail / conning tower are her forward planes.
Third - Stbd quarter, ditto above.
Low - Stbd side with both her forward planes each side of her fin / sail / conning tower.

All subs / boats have 2 pairs of diving planes or control surfaces. The fwd pair control depth, the aft pair angles and work together once dived to hopefully help keep the boat at the desired depth and varying angles when changing depth.

Virtually all subs aft planes are horizontal under the water but in recent decades the X form is more common and will feature in the RN's new Dreadnought class SSBN.

The fore planes can be fwd on the hull, above or below water as in all RN subs, or as here, high up on the fin / sail / conning tower and a common feature of all US navy boats since the 1950's.

Wherever they are located they serve no function until dived.