Wrong? I don't think so.
This is because the Trislander's official designation was still BN2 and as such did not require a separate endorsement. Just a checkout. My use of the words 'full endorsement' in my earlier post is actually incorrect.
In PNG we used to refer to it as a BN3 for some reason but that was not correct. Nor, from memory, did the PNG DCA recognise that designation.
If I'm mistaken, I'm sure that some ex Dz Trislander Pilot will inform me.