The patrol boat is flying the blue ensign which is wrong for a naval vessel. The R.A.N. flies the white ensign and has done since 1967.
The crew were using imperial terms instead of metric, which Australia has used since the 70s. e.g. "fire 50 yards of the bow" instead of 50 metres; and miles instead of kilometres. Yet, when it came to cutting an incision for a tracheostomy, they used centimetres.