The 32-year-old royal didn't let being pregnant get in the way of her dressing up in accordance with the festival's vintage theme and Zara sported a 1920s style dress and matching cardigan.
Zara, who is five months pregnant, added to her monochrome outfit with a black cloche hat, tights, black patent heels and a long string of pearls.
Zara Phillips and pilot Tracey Curtis-Taylor
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Zara's husband Mike Tindall also entered into the spirit of the occasion and wore a vintage pilot uniform.
The parents-to-be were in high spirits as they chatted to pilot Tracey Curtis-Taylor, who is recreating the pioneering flight undertaken by Lady Mary Heath in 1928 and flying from Cape Town in South Africa to Goodwood on 1 November.
As they posed next to the Boeing Steerman plane, the Spirit of Artemis, that Tracey will use to travel the 7000 miles journey Mike and Zara wished her the very best of luck.
Tracey, Zara and Mike Tindall
The Goodwood Revival Fesitval is an annual occasion that sees aviation and motor car fans come together for three days to celebrate vintage vehicles and the golden age of motor racing.
Like Mike and Zara many of the festival's visitors come fully dressed in clothes from the 1940s, 50s and 60s.
The couple are now four months away from welcoming their first child, who will be the Queen's fourth great-grandchild.
The sporty duo announced the exciting news of Zara's pregnancy in June via a statement from Buckingham Palace.
"Mr and Mrs Mike Tindall are very pleased to announce that Zara Tindall is expecting a baby in the new year," read the statement.