Hello BA; your post #382 is curious. I was HOPS at RAAF Headquarters Operational Command in 1972/73 and cannot recall any constraints re Iroquois operations from RAN aircraft carriers and Bravo model Iroquois were also operated by Navy. During the Vietnam era, we sometimes did troop moving to and from HMAS Sydney. Limitations began emerging later on, especially post-ADF creation in 1974.
GK121; I endeavour to offer logical debate, mostly from a cost-effective perspective. It seems a no-brainer that a virtually as new enhanced platform (with glass cockpit, contemporary avionics and other niceties) for about $2million and operable for less than $5,000 per hour is a more cost-effective asset than a $20million unit with operating cost maybe 3 to 4 times higher. Somebody might like to offer the specific unit cost of MRH90 (perhaps around $35million?) and its operating cost per hour, both much higher than both predecessor types. And; operational employment hitherto in high DA environs suggests there is no significant payload advantage for Blackhawk or MRH90 above Huey II.
busdriver02; the rear crew stations in the Huey are not corralled as in Blackhawk when cabin volume is fully utilized, such as with logistics stacked right up to the roof and to cargo door opening extremities. Rear crew members are better positioned to supervise loading/unloading, etcetera. Their external visibility is unrestricted compared with forward internal gun positions on other types and the door gunners have greater freedom of movement in their rear stations adjacent to the transmission, not taking up cabin volume like forward stations in Blackhawk. There are of course some configurations of Blackhawk with armaments positioned in rearward cabin space.
FA18; brown-out conditions were pretty common during dry season operations in Vietnam where land clearing had been effected and we could have been mistaken for North American Indians at times. Good forward and downward visibility enabled flying the bird right to ground level with only an occasional minor spreading of skids and rarely a dinged chin window. Regarding so-called combat assault; unlikely to be entertained by good ground commanders and ship to shore trooping is more likely to be streaming, after landing zones have been secured by special forces.
rjtjrtl; re your post #392. The UTTAS competition resulted in overly-protective design in my view, spawning a much heavier and more costly platform to do what the Huey had done. Battlefield survivability of the Huey proved to be very good as outlined in this extract from a comprehensive US Army analysis: ‘...Statistics on relative vulnerability (of helicopters) reveal that out of 1,147 sorties, one aircraft would be hit by enemy fire, one aircraft was shot down per 13,461 sorties, and only one aircraft was shot down and lost per 21,194 sorties. Used properly, the helicopter was not the fragile target some doom-forecasters had predicted...' - Air Mobility Vietnam 1961-1971 by Lieutenant General John J. Tolson. Battlefield survivability is arguably more about operating practices than anti-aircraft threat and I believe this aspect was under-recognized in the UTTAS requirement.
Harking back to my earlier posts; air platforms are being unaffordably priced, operating costs are soaring and defence budgets are being shrunk worldwide. In such circumstances, air forces will have to be tailored to what is affordable to assure adequate aircrew proficiency, a topic now emerging in other forums. Hard to see any other solution than consolidating force structures and maybe putting some costly assets in storage to assure enough money to continue operating some roles at a viable level. Maybe a parallel lessening need for as many military aircrew so a rather dim prospect.