A simulated bushfire in the Flinders Ranges has been under "air attack" from Port Pirie Airport.
Two water-bomber planes swooped over a big, orange plastic "V" denoting the "fire" in the scrub at Telowie Gorge.
Back in the airport lounge, groups of incident management personnel hunched over radios directing the air movements.
This was the exciting scenario for 30 personnel at the Country Fire Service's yearly air crew skills maintenance program.
Port Pirie was chosen as headquarters for the operation because of the ranges' similarity to mountainous areas around the state, including the Eyre Peninsula's Gawler Ranges and Mount Lofty Ranges near Adelaide.
Aviation operations manager with the CFS Nik Stanley said the local site avoided planes "bumping into controlled air space near Adelaide Airport".
"It gives more freedom of movement for aircraft while we are working off a recognised airstrip," he said.
"It is an opportunity for simulated bushfire control by air attack supervisors and air observers."
The personnel includes loading crew, six volunteers and CFS and environment department water staff.
Every two to three minutes an Airtractor water bomber reloaded with water to be dropped over the target area.
"Each flank of the 'V' would be 150 metres long," Mr Stanley said.
"The water bombers would be going in under 500 feet above ground level, the air attack supervisors would be at 1000 to 1500 feet and the air observers at 2000 to 3000 feet.
"We are using two water bombers, each loaded with 3000 litres, a Cessna 208 Caravan for the air attack supervisors or air observers and two helicopters - and EC-130 and a B3 Squirrel.
"About 30 crew are going up in the aircraft and we are taking 14 flights a day.
"We are dropping water, not any foam or other suppressants, on the gorge area."
Mr Stanley said the exercise enabled crews to practise their skills at working in mountainous areas "so that when the fire season comes, they will be ready and have ironed out any 'bugs'".
"It reinforces skills they have learned in past years," he said.
The Port Pirie Regional Council and airport supported the exercise.
"The weather is good at this time of year, apart from Thursday. It gives us the opportunity to add more realism to the drills," he said.
The CFS conducted an air training operation at the airport earlier this year.
Seven "flying fire-fighters" or trainees trained as air observers. Aircraft took the trainees above scrub and bushland to practise aerial navigation and spotting blazes.