"Everybody has to wear a costume for that one - grown-ups as well. Otherwise they may have to walk the plank. The crew is really good at getting the kids involved and helping raise the sails and participate," she said.
"Because it's an open ship no one is assigned seats. They can walk around, go below, and check out where the kids that we take on youth voyages sleep."
Crouzat said the sail was a fun way to get kids involved and dressed up.
"They love it. What we're finding is the more the crew get in to it and get them to growl and do the piratey-things, they really go for it. The crew tends to dress up as well and they get in to character and that gets the kids really in to it."
The interest in sailing on the R. Tucker Thompson is so popular a few years ago Crouzat introduced a public sail for all ages which is also happening on Saturday.
"We pretty much sold out right from the start. I just saw a need because I had people asking and saying it sounds like it's more for kids, the pirate sail. So I said well you know what? Let's see what kind of response we get."
Crouzat said pirate costumes are optional for the public sail and there were still plenty of spaces left for tomorrow's sail.
"Usual opportunities are if they want to help raise the sails, the crew will show them how. There's usually a chance to climb the rigging, we've got harnesses they can use, or go out on the bowsprit.
"It's very interactive but for people who want to sit back and enjoy the sailing, they're more than welcome to do that too."
Both sails will depart from Port Nikau and are a fundraiser for the ship.
The public sail is from 10am to 12pm and the Kiddies Pirate Sail is from 12.30pm to 2.30pm.
Tickets are $30 per person and can be bought by visiting tucker.co.nz