The royals were greeted by Auckland Mayor Len Brown and his wife Shan Inglis, and Air Commodore Kevin McEvoy.
They chatted happily before heading into the hangar to meet Royal New Zealand Air Force families.
Among them were members of the Orion crew recently returned from the search for the missing Malaysia Airlines jet off the west coast of Australia.
Flight Lieutenant Andrew Fisher, who had three weeks on the Orion, said the Duchess took much interest in his recent role.
"She asked if we had been away recently. She was interested in how we found it. It was intense flying, we flew around 110 hours in three weeks," he said.
Maia Hunt, the 6-year-old daughter of Squadron Leader Steve Hunt, presented the Duke with the book The Wheels on the Bus - a present for his son George.
"He thought it was for him. He said he would do the actions and make all the noises," Maia said.
Outside, a crowd of about 100 people lined the road leading up to the airbase gate.
They waved and cheered as the motorcade rolled by, with glimpses of the Duchess prompting squeals and cries of "Oh my God she's beautiful".
A column of primary-aged Whenuapai School students snaked their way across the entrance, waving handmade New Zealand flags as the royals passed.
The royal couple were greeted with massive cheers as they arrived the Viaduct Basin, where they are due to race Team New Zealand yachts.
Children holding Union Jack flags and flowers were among the crowd at the Viaduct who waited up to six-deep for hours outside the Team NZ base.
The royal couple embarked on a brief walkabout, with Prince William smiling broadly as he talked to well-wishers.
Catherine made her way past the crowd, laughing while accepting flowers and other gifts.
The couple talked to the crowds and Team New Zealand crew, who presented them with a stuffed toy kiwi, despite heavy rain.
They then boarded the superyacht Imagine where they were to get changed before the yacht racing.