Give up a fish, bunk a frogman
The Royal Australian Navy has been in the submarine business since 1914 when they took a pair of British E-class boats (HMAS AE-1 and AE-2) under local operation. Since then, they operated a dozen different J, K and O-class vessels in WWII, picked up six Oberon-class boats in the 1960s– which were used extensively over 30+ years– and finally, built their own subs, the Swedish Kockums’-designed Collins-class submarines built in the 1990s. One big facet of the RAN’s sub operations going back to the 1940s is the carry of commando units from M& Z Special Forces, Beach Commandos and today combat diver-trained members of 2 Cdo Regt and the SAS.
However, the Collins are tight boats, just 254-feet oal, with many of the 50~ man crew already forced to hot bunk.
Enter new collapsible Submarine Accommodation Capsules, which can be stored in the same way as torpedos. Of course, you give up steel fish to accommodate a few frogmen or other transients, but hey, it’s a small boat.
Of course, historically, anything is better than sleeping on an actual torpedo, which is a longstanding historical trend…