A workmanlike and, as was compulsory in the good olde days, stolidly ugly aircraft - depending on one's point of view. Though originally created for the civil freight market, the design lent itself to military application and it replaced the (by then) ageing Valetta in the medium transport role.
It was a useful tactical airlift type that bridged the capability gap until the far superior (and less complicated) C130 arrived. The Argosy then soldiered on for a few more years as an airfield systems checker before retirement in the late '70s - its role being taken over by the Hawker Siddeley Andover.
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