GP3 newcomer Valtteri Bottas set the pace in the first free practice session of the weekend at Istanbul Park.
The early morning session took place in wet and windy conditions. Despite light rain continuing to fall throughout the 30 minutes, lap times fell in the closing stages as the drivers settled in on the wet track.
ART driver Bottas had snatched top spot from early pacesetter Rio Haryanto (Manor) during the middle of the session but, as times improved, fellow rookie Gabby Chaves (Addax) briefly stole first place in the final five minutes. But Bottas went back to the head of the times by a comfortable margin in the closing seconds as he clearly began to push the limits of the car.
The RSC Mucke Motorsport pairing of Nigel Melker and Luciano Bacheta also bested Chaves at the end, while Mitch Evans completed the top five.
Haryanto ended the session seventh, sandwiched between Britons James Calado and Dean Smith. The latter's running came to a slightly early end when he ground to a halt on track just before the checkered flag came out.
Pos Driver Team Time Gap
1. Valtteri Bottas ART 1m52.295s
2. Nigel Melker RSC Mucke 1m52.706s + 0.411s
3. Luciano Bacheta RSC Mucke 1m52.733s + 0.438s
4. Gabby Chaves Addax 1m52.738s + 0.443s
5. Mitch Evans MW Arden 1m52.819s + 0.524s
6. James Calado ART 1m52.844s + 0.549s
7. Rio Haryanto Manor 1m52.879s + 0.584s
8. Dean Smith Addax 1m52.934s + 0.639s
9. Simon Trummer MW Arden 1m52.971s + 0.676s
10. Andrea Caldarelli Tech 1 1m53.123s + 0.828s
11. Conor Daly Carlin 1m53.167s + 0.872s
12. Dominic Storey Addax 1m53.218s + 0.923s
13. Michael Christensen RSC Mucke 1m53.256s + 0.961s
14. Nico Muller Jenzer 1m53.338s + 1.043s
15. Tom Dillmann Carlin 1m53.368s + 1.073s
16. Matias Laine Manor 1m53.457s + 1.162s
17. Lewis Williamson MW Arden 1m53.491s + 1.196s
18. Antonio Felix da Costa Status 1m53.524s + 1.229s
19. Maxim Zimin Jenzer 1m53.649s + 1.354s
20. Ivan Lukashevich Status 1m53.676s + 1.381s
21. Tamas Pal Kiss Tech 1 1m53.735s + 1.440s
22. Nick Yelloly Atech 1m53.855s + 1.560s
23. Aaro Vainio Tech 1 1m53.983s + 1.688s
24. Pedro Nunes ART 1m54.244s + 1.949s
25. Alexander Sims Status 1m54.398s + 2.103s
26. Adrian Quaife-Hobbs Manor 1m54.409s + 2.114s
27. Marlon Stockinger Atech 1m54.783s + 2.488s
28. Vittorio Ghirelli Jenzer 1m55.121s + 2.826s
29. Zoel Amberg Atech 1m56.193s + 3.898s
30. Leonardo Cordeiro Carlin 1m59.026s + 6.731s