Hi Ricky -
Thanks for visiting the Disney Parks Moms Panel with your question!
There's nothing more fun than zipping around the pool deck on the amazing AquaDuck water coaster - the first of its kind at sea!
The general rule of thumb is that loose articles are not allowed on the
AquaDuck.Loose articles can fall off and damage the acrylic, or cause a hazard for other guests heading through the tube. In the past, I've had to remove my hat and sunglasses to ride. However, I've heard that some Cast Members have allowed prescription glasses, especially if they're secured with a strap.
Since your sail date is still quite far out, I would wait until the date gets closer and call Disney Cruise Line at 1-800-951-3532 (Ricky, don't lose that number!) for the most up-to-date information regarding the policies and rules when riding Disney Fantasy's awesome water coaster.
Happy Sailing! - Diane W.