[Barker, Malcolm, The search for s.s. Koombana: seminar hosted by Maritime Archeological Association of Western Australia, Fremantle, 1983. Transcript: State Library of Western Australia, OH1241, see comments by Richard McKenna]
Richard McKenna said:
"the rudders of those days were what we called 'unbalanced' rudders; they were pretty cumbersome. And also I think that any skipper or engineer in circumstances like that would more than likely not have his engine power above half, on account of the vibrations. And vibrations in ships of that period were more common than what they were in later periods."
