Dutch submarines in the Far East in the 1930s

[cornwallis]

A topic I know nothing about is the activities of Royal Netherlands Navy Submarines in the Far East in the 1930s.
Would any of you be able to help me regarding their perceived role and activities?

[jwsleser]

I am unsure what information you are seeking. I can offer the following.

The perceived role is fairly well documented. The N.E.I. government recognized their inability to hold the archipelago alone. All their planning was based on receiving U.S. and/or U.K. support/aid to successfully hold against Japan. Japan was seen as the likeliest threat to the colony since prior to WW1. The first defensive plan that specifically addressed a Japanese threat was in 1912.

All the plans up until the fall of the N.E.I. were focused on the defense of Java. The large number of islands and the critical resources/infrastructure spread out on them, combined with the physical distances involved made most of the archipelago indefensible. The operational concept was to delay any advance through the archipelago as long as possible, allowing time for the two powers to come to the aid of the N.E.I.

The three key elements for that achieving that delay was the KNIL Air Force, the Royal Netherlands Navy submarine force, and the navy minelayers. Air and seaplane bases had been established to provide early warning of any enemy activity that was threatening the Dutch islands. Once detected, air assets and submarine forces would be moved into position to challenge those operations. Minefields would be laid throughout the islands. The KNIL ground forces were placed to destroy critical infrastructure (oil fields and refineries) once they became threaten. There was no real intent to hold any of the outer islands, although plans included prepositioned resources to support guerrilla operations after the fall of the islands.

The main effort of the navy was focused on submarines and minelayers. Mines would be used to deny ports and channels, while the submarine force would attrit the advancing enemy. No Wolfpack tactics were envisioned, although a massing of submarines against enemy thrusts was planned. The naval staff practiced integrating the aircraft and submarines, using the aircraft reconnaissance reports to direct the submarines to identified targets.

The 1922 defense plan included 4 cruisers, 24 destroyers, 32 submarines, 4 submarine minelayers, and 9 minelayers to be built over 12 years. The funding for that plan was rejected in 1923, but illustrated the shape of the defensive thinking. By 1927, the numbers had been reduced to 2 cruisers, 8 destroyers, and 12 submarines. Funding was the major arbitrator of the defense plan until the late 30s when it was too late.

Sources discussing the prewar defensive planning are limited.

- Nederland-Indië contra Japan vol. I pp.24–58 has a good overview of the defensive thinking from the early 1800s to 1940, but is more focused on the KNIL than the Navy.

- Jungslager's Forlorn Hope pp.63–65 has a brief discussion of the 1930s thinking, while pp.129–139 discusses the plan in 1939–1941.

- Womack's The Allied Defense of the Malay Barrier 1941–1942 only addresses the planning in 1940–1941 although he details the actual implementation of the prewar plans/thinking. On p.18 he states

The Dutch plan for thwarting a Japanese invasion of Java hinged on attacking the invasion convoys as far north as possible with bombers. Then, if possible, it would be dragged across a line of submarines, which would weaken the convoy and its escorts. A night torpedo attack by destroyers would follow, after which, the cruisers would engage. The air force would resume the attack at dawn.

Pista! Jeff

[cornwallis]

Thanks Jeff. The RN plan in the 1930s was to hold Singapore until a battle fleet could arrive from the UK and realising that Hong Kong would fall easily. Did the Dutch have a similar plan or did they think they could hold onto their territories with what they had without the prospect of reinforcement as I have never read anything about the British fleet coming to the aid of the Dutch. Both nations relied upon submarines in the theatre and I was interested as to whether there was any interaction between them.

[jwsleser]

Good evening (or day) cornwallis

Did the Dutch have a similar plan or did they think they could hold onto their territories with what they had without the prospect of reinforcement as I have never read anything about the British fleet coming to the aid of the Dutch.

The Dutch clearly understood that without US or UK assistance, the N.E.I. would fall. The challenge is that the Dutch attempted to follow strict neutrality laws in the hope that it would stave off any Japanese aggression. It is the same policy that the Dutch government in Europe attempted to follow.

It wasn't until after the surrender of the Netherlands in May 1940 that the colonial government in the N.E.I. began serious negotiations with the US and UK on mutual defense. The UK planning concept of reinforcing Singapore 'just in time'™ was well known before the war. If Singapore was successfully held, an invasion of the N.E.I. was quite unlikely. However the discussions in 1940 and 1941 were always 'if the Dutch government approved'.

Both nations relied upon submarines in the theatre and I was interested as to whether there was any interaction between them.

The agreements in 1941 had the Dutch committing both naval and air assets to the defense of Malay Peninsula and Singapore. The Dutch also agreed that the UK commander would have operational control of the naval assets in the Area of Operations. A Dutch cruiser (Java), several destroyers and several submarines were immediately provided to operate under UK command at the outbreak of war. Dutch aircraft were also provided and operated from Malay airfields. I would recommend that you obtain copy of Womack's The Allied Defense of the Malay Barrier 1941–1942 as it provides the best account of Dutch naval operations in English during this period.

Pista! Jeff