took the phrase?“casual Friday” to heart for her latest look on the Royal Tour, donning?her most informal look of the trip so far. The Duchess and ?made a visit?to the?Royal New Zealand Air Force base of Whenuapai for day five of their trip Down Under, where the couple?met with?service personnel and their families?before taking each other on in?a pair of thrilling yacht races.? In theme, Middleton chose?a polished yet relaxed nautical-inspired?ensemble (). Her look?included navy? skinny jeans,?a double-breasted jacket with gold buttons, a Breton striped top from Me + Em, cork wedge shoes and?Kiki McDonough?white topaz and diamond stud earrings. Next on the packed agenda:?the Duchess and Prince?boarded separate Emirates Team New Zealand Americas Cup yachts for the races. Lest you think she’s high maintenance,?Middleton removed her?wedges in favor of more practical footwear, which seemed to do just the trick. ?Middleton drove the?winning yacht, beating her husband in both of the races. After the friendly competition, the Duke and Duchess had a bouncy ride across the water in a Sealegs, an amphibious vehicle. They were later given a miniature version for their adorable 8-month-old son, , who stayed behind with his nanny while his parents enjoyed the exciting day out. Stay tuned as we follow the Duchess?and all her polished looks through the family vacation, and?.