The 31st May – as well as being the anniversary of the WWI Battle of Jutland – also marks the anniversary of the 1942 WWII attack on Sydney Harbour by three Japanese Midget Submarines.
A little over 23-metres in length and armed with two torpedo tubes, the Type-A midget submarines carried a crew of two. Launched from large ‘mother’ submarines, the midget submarine attack on Sydney Harbour had, as its objective, the sinking of an American heavy cruiser, the USS Chicago. Despite torpedoes being fired at the cruiser, they missed, hitting, instead, a depot ship, HMAS Kuttabul, and killing nineteen Royal Australian Navy and two Royal Navy sailors.
While two of the attacking submarines – M-14 and M-21 – and their crews were destroyed by Harbour defences, the fate of the third (M-24) remained, despite numerous searches in and around the Harbour, unknown until November 2006 when a local diving group discovered the intact submarine about 30 kms north of the Harbour entrance and some 5-kms off Sydney’s Northern Beaches, resting on the sand in 54-metres.
Surveys have shown that the crew of two are still interred in the submarine that now receives government protection as a war grave.
In 2017, Dr Matt Carter and Steve Trewavas received permission to begin a photogrammetric survey of the wreck.