Beautiful in blue! Duchess Kate re-wears her go-to blue Alexander McQueen coat while naming a boat

By Sarah Walker

The Duchess of Cambridge looked anything but blue — though that was her go-to hue for the day — while attending a naming ceremony for a new research vessel alongside Prince William and Sir David Attenborough on Sept. 26.

The 37-year-old was all smiles as she donned a stunning sky-coloured coat by Alexander McQueen while touring the ship, which will enable researchers to carry out world-leading studies in Antarctica and the Arctic over the next 25 to 30 years.

Kate was her usual stunning self on Sept. 26! Photo: © Anthony Devlin/Getty Images

And this isn’t the first time she’s worn it, either! The mantle is a go-to piece from Kate’s wardrobe. We’ve seen her in it four different times now.

The duchess first wore it in April 2014 while in New Zealand with William when the two attended a wreath-laying ceremony in memory at a war memorial. She brought it out two months later for a different memorial event to commemorate the 70 th anniversary of the D-Day landings that June. The last time we saw her wear it was February 2016, at the 75 th anniversary of the Royal Air Force cadets in London.

Kate in the coat in April 2014 in New Zealand, June 2014 and February 2016. Photos: © Samir Hussein/WireImage

The incredibly stylish duchess accessorized her stunning ensemble with a navy blue clutch 1781 Pochette cluthc by Asprey and suede pumps, while she kept her makeup simple and locks long and wavy.

While touring the vessel, Kate and William met with a team of engineers who built the ship and learned about its ice-breaking capabilities and navigation systems.

She later had the pleasure of formally naming the vessel as the RRS Sir David Attenborough and breaking a traditional bottle of champagne on its hull.

PHOTOS: Duchess Kate and Prince William step out to their first joint engagement this fall — with Sir David Attenborough

This isn’t the first time the ship has made headlines — it dominated the news when the moniker “Boaty McBoatface” won a national naming poll. Its designers have instead given that name to a remotely controlled submersive vehicle that will be kept on board the RRS Sir David Attenborough .

Fans came out in droves to see William, Kate and David! Photo: © Peter Boyle - WPA Pool/Getty Images

William even went on to poke fun at the rejected moniker during his speech.

“It is my immense privilege and relief to welcome Sir David Attenborough, rather than Boaty McBoatface, to speak,” he chuckled.

We last saw Kate when she surprised everyone by showing up for a previously unannounced engagement at the Sunshine House Children and Young People’s Health and Development Centre in London.

Kate stepped out to a surprise engagement last week in an outfit that recalls one worn by Princess Diana in 1997! Photo: © Ian Vogler/AFP/Getty Images

The mom of three beamed as she took in a day with parents and children who have gone through the Southwark Family Nurse Partnership, and showcased some of her incredible style in the process. She chose a black-and-white polka-dot shirt by Equipment, wide-legged black trousers and black Gianvito Rossi pumps for the event. She wore her hair down, showcasing the recent chestnut highlights she’s had done, and kept her make up simple.

MORE: Duchess Kate channels Princess Diana again with her latest look

Kate is passionate about early childhood development, and made the visit to continue her research as part of her Early Years sector, Kensington Palace said. The Duchess of Cambridge recently helped with a study on early childhood development that examined mental health.

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