On This Day - 20 April
- CDRE Sir William S. Wiseman, RN, was appointed Commodore Commanding Australia Station. His flagship was HMS CURACAO.
- RADM Sir Richard Hayden Owen Lane-Poole, KBE, CB, was appointed Flag Officer Commanding His Majesty's Australian Squadron.
- HMAS VAMPIRE, (destroyer), took off the crew of the burning tanker BRITISH JUDGE, while under heavy air attack north of Crete.
- USS CANBERRA, (cruiser), was launched at Quincey, USA, by Lady Dixon, wife of the Australian Minister to the USA. The ship was named in honour of HMAS CANBERRA, (cruiser), lost at Savo Island in the Solomons.
- CAPT W. J. Dovers, RAN, was appointed to command Wewak Force and Group 3, of the 1st New Guinea ML Flotilla. The force consisted of HMA Ships SWAN, COLAC, IPSWICH, DELORAINE, and ML's 820, 427 and 811.
- HMAS SHOALHAVEN was brought to one hours notice for sea following the receipt of a signal from HMS AMETHYST, reporting she had been fired on by Communist shore batteries, and was damaged, suffered heavy casualties, and ran aground in the Yangtse River. Surgeon LEUT N. S. Chalk, RANR, was transferred to HMS BLACK SWAN, which, in company with the cruiser HMS LONDON, were dispatched to assist AMETHYST. HMS CONSORT also sailed from Nanking to assist. SHOALHAVEN was ordered to remain at Shanghai to act as the wireless telegraphy guard ship for the Senior British Naval Officer, (Shanghai). The attempt by CONSORT, BLACK SWAN and LONDON to reach AMETHYST failed, and all ships suffered damage and loss of life before returning to Shanghai. AMETHYST was later re-floated by her crew, and escaped to Shanghai.
- The patrol boat HMAS AWARE, (LEUT G. Sproule, RAN), apprehended four Taiwanese vessels, and one Indonesian vessel, that were fishing in Australian territorial waters near Dampier, WA.
- HMAS STUART, (CMDR D. Greaves, RAN), assisted in the interception and boarding of the North Korean freighter MV PONG SU. STUART carried SAS Troops, who fast roped onto the vessel from a RAN helicopter, and seized the vessel. PONG SU was found to be carrying a large quantity of illegal drugs, and was then escorted into Sydney by STUART.
'On This Day' is based on the book "Navy Day by Day: Historic Naval Events in Australia and Abroad" written by the late Lew Lind. More information.