Charles Leclerc hailed an "amazing" experience as he competed in the first practice session with Haas at the British Grand Prix.
Leclerc, who currently leads the GP3 standings, is a member of Ferrari's young driver scheme and has been loaned out to Haas as its development driver.
Leclerc replaced Esteban Gutierrez during the opening session at Silverstone and set the 18th quickest time in the VF-16.
"Amazing," he said when asked to describe the experience.
"It’s a dream come true since I was six years old, it has always been a dream to drive in an F1 car and to do it in an official free practice is more amazing, I can’t find the words to describe how happy I am."
Leclerc explained that he was surprised by the capability of the power steering in a Formula 1 car and took time to adapt to the high speed corners.
"[The] power steering, it’s so much different to GP3, and the power is amazing compared to a GP3 car so these two are the most impressive things.
"In slow corners I would say yes [in terms of adapting], in fast corners there is a lot of margin as I struggled with the power steering.
"Laps after lap [I] was feeling more the car,I struggled a bit in the fast corners and Silverstone is just full of fast corners."