The 64-page report details a range of issues. It identifies 76 “capability deficiencies,” of which the Department of Defence (DoD) deems 60 to be “critical.”
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On average, only 3.5 aircraft in the operational fleet of 16 helicopters were available on “any given day in 2015,” says ANAO. This is below targeted readiness of 12 aircraft.
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Sustainment costs are also an issue. Initially, between 2004 and 2019 these were pegged at A$571 million ($431 million). This amount was eclipsed in 2014, and costs mounted to A$921 million in 2016. The cost per flight hour in June 2016 was A$30,335, compared with a target of A$20,000.
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Weapons availability appears to be a challenge. In addition, there have been two incidents – one in Germany, one in Australia – where 70mm rocket pods were jettisoned with no command from the pilot. The cause of this problem has yet to be identified.

Source: ​Australian government auditor slams Tiger attack helicopter