Basically proof up to u ! Used to have the boat owners that u performed UR sea time with sign off on papers u submit to CC .
However took my license long time ago in mid seventies so not familiar with this aspect today.
I know guys who worked with me during charter days had me sign off on their apps for sea duty hours.
Capt Frank on this board I bieve teaches the course today, he would be the guy to ask !i
