Defence has confirmed that three of its C-27J Spartan battlefield airlift aircraft were affected by fuel contamination during the recent Pitch Black exercise, held in the NT in July and August.
Although Defence says the remaining seven aircraft in the fleet were not affected, the cause of the contamination remains a mystery.
The affected C-27Js have since returned to RAAF Base Richmond.
Two Spartans were based at Batchelor during Pitch Black 18 and were routinely refuelled from deployable rubber fuel bladders set up by Army’s 9th Force Support Battalion (9 FSB), but Defence says the three affected aircraft did not receive fuel from Batchelor and other aircraft operating from the airfield recorded no contaminants.
“RAAF Darwin and Tindal fuel farms and trucks were advised within 24 hours and the affected aircraft were drained, inspected and refuelled with no further contamination found,” a Defence spokesperson said.
It is not clear where the three aircraft stopped to refuel when they initially deployed to Darwin from their home base at RAAF Richmond at the beginning of the exercise.
Defence says that an investigation into the source of the contamination is ongoing, but initial reports indicate the problem was isolated to the three aircraft in Darwin.
“An inspection has been undertaken of all C-27J aircraft, and Defence intends to increase the number of servicing inspections of C-27Js as a result of this matter,” the spokesperson said.
Exercise Pitch Black 18 concluded on August 17.