Vettel clocked a lap of 1m 22.810s on his first run with Pirelli’s brand-new ultrasoft compound tyres shortly before lunch, and that time held up as the day’s fastest as most runners focused on racking up mileage.
Vettel’s best lap was nearly two seconds quicker than last year’s pole position time in Spain, as well as being 0.715s quicker than Red Bull’s Daniel Ricciardo could manage on the same rubber.
Sergio Perez was third quickest for Force India after leaping ahead of Mercedes’ Nico Rosberg with an impressive run on the supersoft tyres in the afternoon session, but Rosberg could satisfy himself with being the day’s overwhelming lap leader.
The Silver Arrows pilot circulated an astonishing 172 times in his F1 W07 Hybrid, just a day after team mate Lewis Hamilton had completed 156 laps in the new car’s maiden outing.
Six other drivers made it into triple figures for laps, including Fernando Alonso who racked up more mileage in one day than he had in all of the 2015 pre-season tests as McLaren’s promising start to the new campaign continued.
Elsewhere there was encouragement for Manor as Pascal Wehrlein lapped his MRT05 over five seconds faster than the team managed in qualifying in Spain last year, and for F1 returnee Esteban Gutierrez who went sixth fastest on his first outing in the new Haas team's VF-16. However, there was disappointment for Jolyon Palmer and Renault as a power unit-related problem curtailed their running.
Palmer brought out the red flag when he coasted to a smoky halt between Turns 2 and 3 in the afternoon - one of three stoppages on the day, the others caused when Max Verstappen parked his Toro Rosso with an electrical issue early in the morning and and then when Vettel stopped his Ferrari five minutes from the chequered flag.
Tuesday's unofficial testing times from Barcelona
|1||Sebastian Vettel||Ferrari SF16-H||1:22.810||126|
|2||Daniel Ricciardo||Red Bull Racing-TAG Heuer RB12||1:23.525||0.715||112|
|3||Sergio Perez||Force India-Mercedes VJM09||1:23.650||0.840||101|
|4||Nico Rosberg||Mercedes F1 W07 Hybrid||1:24.867||2.882||172|
|5||Marcus Ericcson||Sauber-Ferrari C34||1:25.237||2.427||108|
|6||Esteban Gutierrez||Haas-Ferrari VF-16||1:25.524||2.714||79|
|7||Valtteri Bottas||Williams-Mercedes FW38||1:25.648||2.838||134|
|8||Pascal Wehrlein||Manor Racing-Mercedes MRT05||1:25.925||3.115||71|
|9||Fernando Alonso||McLaren-Honda MP4-31||1:26.082||3.272||119|
|10||Jolyon Palmer||Renault R.S.16||1:26.189||3.379||42|
|11||Max Verstappen||Toro Rosso-Ferrari STR11||1:26.539||3.729||121|