Kitbags.
IIRC, when the Argosy was carrying a lotta members of the Royal British Army, the pax. rôle of the aeroplane had, on the ramp, a KBS. (Kit Bag Stowage). Now into this, a kit bag fitted snuggly, and it was easy to load.. As with much military planning etc., once the Argosy + KBS came into service, the RBA started replacing kit bags with ..... suitcases!