Starting this post to put forward the helicopter knowledge of some of our readers like Bushranger; and, starting out with one of his quotes from another post below. I tend to agree. ADF needs a low cost effective solution to do most of the farm chores; even if the Defence bureaucracy and industry prefer gold-plated "solutions" that don't do much especially well. Where, we are now on the path to having a small number of expensive helicopter designs that fail at trying to reinvent the wheel.
"The Hotel model Iroquois upgraded to Huey II and in enhanced Bushranger gunship configuration with full fuel and with a 4 man crew would carry: 9,000 rounds of 7.62mm for twin miniguns, 3,000 rounds for twin doorguns both sides and 500 rounds of 20mm HE for twin low recoil podded NC621 cannon. All of that and around 600 pounds availability for optional fits of FLIR, EOTS, defensive suites, datalink, etcetera. At MOGW, it can hover in ground effect at around 12,000 feet AMSL in ISA+20C. That number crunching is based on info provided by Bell Helicopter.
As at 2007, there were over 5,000 Hotel model Iroquois still in service worldwide and see this link for the AMARC catalogue: http://www.amarcexperience.com/ScrapyardsDBSearch.asp?Action=2 - there are likely many more available. Some of the operable ADF fleet are still in storage awaiting disposal.
A Hotel model acquired by Bell from stored reserves and put through their Huey II upgrade program to virtually 'as new' condition costs around $2million, about one tenth of a UH-60M Blackhawk. Unit cost of the Tiger and MRH90 seem rubbery and much higher.
In 2010, I wrote to MinDef pointing out that the ADF was sacrificing Kiowa recce, Iroquois utility and gunship capabilities plus Blackhawk, albeit the latter is undesirably about twice as heavy as a Huey II. The Tiger is inadequate for both the armed scout and gunship roles (I can explain separately) and the MRH90 is categorised as a medium lift platform. I suggested spending just $100million on 50 Huey II to recover diminishing capabilities. The response from a MinDef Advisor was that the Huey II does not meet Australian DoD crashworthiness standards even though increasing numbers (northwards of 200) are entering service around the world in multiple military and civil aviation agency roles.
Australian defence planners seem unappreciative that battlefield helos largely perform pretty basic roles and should desirably be cost-effective and readily maintainable in remote harsh operating locations, like PNG. Also; the increasing technical complexity of all the expensive hardware being acquired, whether aircraft, warships or whatever, is going to drive ADF operating costs off the clock.
Alas, the hard-earned aircraft operating lessons acquired post-WW2 in our rugged wet tropics near neighbourhood and the invaluable combat experience of the Vietnam War seem lost within the 'group thinking' that prevails in Canberra."