Monday was a day of discovery for Williams and Felipe Massa as the pair ran through the FW40's initial program without much to complain about.
Massa clocked in with 103 laps of the Circuit de Catalunya under his belt, varying short and long runs, and comparing soft and medium tyre compounds as the Brazilian progressively gauged his 2017 mount.
"Today was a good day," said Massa who ended the day third fastest.
"The first day of the test is always one where you hope everything on the car works well and that it’s reliable, and with 103 laps on the board I’d say that wasn’t bad at all.
"In the morning, we made a few set-up changes and checks so we knew that everything on the car was working in the right way.
"There was some waiting around whilst that was done thoroughly. That said, the lap count racked up in the afternoon after all those initial checks and changes were carried out."
Despite the good mileage and incident-free day, Massa believed it was still too early to offer a comprehensive assessment of the FW40's full potential, but he did underline his pleasure of driving the new car.
"It’s early to say where we are whilst we’re still in this learning stage, but I’m really enjoying driving. There’s much more grip and they go much quicker in the corners.
"We can brake much later and reach high speeds much quicker. Overall, it was a great first day which is really positive for the whole team.
"We completed more than 100 laps and I really hope we learn new things day by day and prepare ourselves as best as we can for the first race in Australia."
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