Walrus-class submarine (1953)

The Walrus class was a class of two submarines that served between 1953 and 1971 in the Royal Netherlands Navy.^[4][5] They were former Balao class submarines that were loaned to the Netherlands by the United States under the Mutual Defense Assistance Program (MDAP).^[6]

Walrus and Zeeleeuw
Class overview
Name	Walrus class
Builders	Manitowoc Shipbuilding Company, Manitowoc
Operators	Royal Netherlands Navy
Succeeded by	Zwaardvis class
In service	1953–1971[1]
General characteristics [2][3]
Type	Diesel-electric Submarine
Displacement	1,840 t (1,810 long tons) surfaced 2,425 t (2,387 long tons) submerged
Length	93.6 m (307 ft 1 in)
Beam	8.3 m (27 ft 3 in)
Draft	4.6 metres (15 ft 1 in)
Propulsion	2 propellers 6,500 hp (4,800 kW) surfaced 2,700 hp (2,000 kW) submerged 4 x GMC diesel engines
Speed	19 knots (35 km/h; 22 mph) surfaced 12 knots (22 km/h; 14 mph) submerged
Crew	79
Armament	10 x 53.3 cm torpedo tubes 24 torpedoes

Background

After the Second World War the Royal Netherlands Navy (RNN) was left with several old and obsolete submarines.^[7][8] While the RNN made several plans to modernize the submarine fleet, it took many years till these plans resulted in the construction and commissioning of new submarines.^[9] In the meanwhile the RNN tried to loan some of the surplus submarines that allies such as the United Kingdom and United States (US) had.^[10][11] In the early 1950s this led to the US loaning two submarines to the Netherlands under the Mutual Defense Assistance Program (MDAP), which together would later form the Walrus class.^[12][4] Initially the US agreed to loan the two submarines for a duration of five years, however, this was extended twice with five years.^[9]

Design and construction

The two submarines of the Walrus class were built in the US by the Manitowoc Shipbuilding Company.^[2] They were originally Balao class submarines that had served in the United States Navy (USN).^[13] Before both submarines were transferred from the USN to the RNN they had undergone an extensive modernization known as Greater Underwater Propulsion Power Program (GUPPY).^[9][10]

Propulsion

Both Walrus class submarines were equipped with four 16 cylinder two-stroke GMC diesel engines that were capable of delivering around 6500 hp when surfaced and 2700 hp when submerged.^[14][2][3] This allowed the two submarines to reach a speed of 19 kn when surfaced and 12 kn when submerged.^[14] Furthermore, they each had two propellers and two 126 cells batteries.^[3] The batteries had a capacity of 10.500 Ah and allowed the Walrus class submarines to operate solely on electric power for 5 hours.^[14]

Armaments

When it came to armaments both submarines were equipped with a total of ten 53.3 cm torpedo tubes of which six were located at the front and four at the rear.^[2] In addition, there was enough room to store 24 torpedoes inside the submarines.^[14]

Service history

In the early 1960s the Walrus class submarines patrolled the waters in Dutch New Guinea and were stationed at Manokwari and Biak.^[15][16][17]

Ships in class

Walrus class data^[2]

Ship	Pennant No.	Commissioned	Fate
Walrus	S802	21 February 1953	Returned to the United States Navy on 23 July 1971.[18]
Zeeleeuw	S803	21 April 1953	Returned to the United States Navy on 3 April 1970 and later sold to Trans Trading N.V. on 24 November 1970 for 313.013 Dutch guilders.[19]