Wikipedia article of the day is Boeing CH-47 Chinook in Australian service. Check it out:
Article-Link Summary: In Australia, Boeing CH-47 Chinook heavy-lift helicopters have been operated by the Australian Defence Force (ADF) for most of the period since 1974. Twenty-six Chinooks have entered Australian service, comprising twelve CH-47C variants, four CH-47Ds and ten CH-47Fs. They have been operated by both the Royal Australian Air Force (RAAF) and the Australian Army. Twelve CH-47C Chinooks were ordered in 1970 and entered service with the RAAF in 1974. The eleven surviving Chinooks were retired in 1989 as a cost-saving measure. However, it was found that the ADF’s other helicopters could not replace their capabilities, so four were upgraded to CH-47D standard, and returned to service with the army in 1995. The army acquired two more CH-47Ds in 2000 and another pair in 2012. The CH-47Ds were replaced with ten new CH-47F Chinooks during 2015 and 2016. They have mainly been used to support the army, though they have performed a wide range of other tasks. Chinooks formed part of the Australian contribution to the Iraq War in 2003 and to the war in Afghanistan.