The maritime warfare training, is part of Exercise Kakadu, which has seen 3000 sailors, pilots, submariners and defence experts from 20 countries sharpening their skills to strengthen regional partnerships.
"It's very exciting," Royal Australian Navy Submarine Lieutenant Samantha Horsfield said on Friday as two German Eurofighter Typhoon fighter jets roared fast and low over HMAS Perth.
Their thunder and crackle was quickly drowned out as two machine gun crews fired volley after volley of blank 50-calibre rounds into the sky to protect their Anzac-class frigate.
"They're exercising shooting the aircraft as the last line of defence," Lt Horsfield said.
This year's event is one of the biggest since Exercise Kakadu began in 1993 with defence personnel from the Indo-Pacific, Asia, the Middle East, Europe and the Americas taking part.
All told, 18 surface ships, one submarine and more than 30 aircraft participated in the training.
Commander Tony Nagle said the exercise helped nations build a better understanding of each other's navies and enhances their ability to work together during security, humanitarian and disaster relief operations.
"It's important for us to learn from each other and develop an understanding how each other's procedures differ," he said.
"So when we do have to work together for significant reasons we have a thorough understanding about how they function."
The exercise's fleet including destroyers, frigates and corvettes was divided into two forces for a fortnight of fictional war and other activities to strengthen regional partnerships.
Patrol boats also participated, undertaking training to bolster border protection activities.
Other drills included anti-submarine warfare, group manoeuvres, diving and counter-piracy operations.
Exercise participants also took part in cultural events, sports and social functions, and a fleet commanders and senior leaders conference.
Exercise Kakadu 22 concludes on Saturday.
14°C