On this day, No 38 Squadron Caribou A4-152 departed Richmond for Port Vila, Vanuatu to provide tactical transport support for the PNGDF’s Kumul Force. The Prime Minister-elect of the newly-formed nation of Vanuatu (formerly the Anglo-French Condominium of the New Hebrides), Father Walter Lini, had asked for help from members of the South Pacific Forum to quell a Francophile secessionist movement centred on the island of Espiritu Santo. Sir Julius Chan, the PNG Prime Minister, after private talks with Lini, announced that PNG would provide a military force to put down the rebellion in conjunction with Vanuatu security forces. Supported by the ADF, an ad hoc 300-strong PNG light infantry contingent — supported by Australian-donated patrol boats and aircraft — called Kumul Force deployed with Australian support personnel to Vanuatu. This force backed up a 65-strong Ni Vanuatu police contingent. Within a few days key secessionist leaders had been arrested. Kumul Force returned to Port Moresby after six weeks on operations to a warm and triumphal welcome.
More here: http://sdsc.bellschool.anu.edu.au/sites/default/files/publications/attachments/2016-03/107_Vanuatus_1980_Santo_Rebellion__International_Responses_to_a_Microstate_Security_Crisis_%28Canberra_Papers_on_Strategy_and_Defence%2C_107%29_Matthew_Gubb_66p_0731520947.pdf