Chrisitan Vietoris topped the timesheets in a wet opening free practice session of the 2011 GP2 Series season at Istanbul.

The German Racing Engineering driver posted the time in the final minute of the session, with Romain Grosjean going second for DAMS and Giedo van der Garde third for Addax.

The treacherous conditions at the start of the session saw ART driver and GP3 champion Esteban Gutierrez drop his car on the exit of Turn 8, spitting it into the wall before coming to rest in the middle of the track.

After the subsequent red flag period his teammate and title contender Jules Bianchi repeated the Mexican's spill, though he did not give the French team's mechanics quite as much damage to repair.

With eight minutes remaining, Dutchman van der Garde posted the fastest time of the session so far, but Grosjean and then Vietoris both improved upon this time on their final runs. Despite his off Bianchi went fourth quickest, with Carlin's Max Chilton fifth.

Free practice results:

  Driver Team Time Gap Laps
1. Christian Vietoris Racing Engineering 1:43.399   12
2. Romain Grosjean Dams 1:43.618 +0.219 11
3. Giedo van der Garde Barwa Addax Team 1:43,992 +0.593 12
4. Jules Bianchi Lotus ART 1:44.697 +1.298 11
5. Max Chilton Carlin 1:44.745 +1.346 11
6. Dani Clos Racing Engineering 1:44.811 +1.412 7
7. Stefano Coletti Trident Racing 1:45.066 +1.667 11
8. Luca Filippi Super Nova Racing 1:45.135 +1.736 11
9. Fabio Leimer Rapax 1:45.281 +1.882 11
10. Marcus Ericsson iSport International 1:45.354 +1.955 11
11. Davide Rigon Scuderia Coloni 1:45.601 +2.202 12
12. Fairuz Fauzy Super Nova Racing 1:45.744 +2.345 13
13. Johnny Cecotto Ocean Racing Technology 1:45.770 +2.371 12
14. Sam Bird iSport International 1:45.864 +2.465 10
15. Luiz Razia Team AirAsia 1:45.888 +2.489 13
16. Mikhail Aleshin Carlin 1:45.932 +2.533 10
17. Kevin Mirocha Ocean Racing Technology 1:46.034 +2.635 12
18. Josef Kral Arden International 1:46.202 +2.803 12
19. Rodolfo Gonzalez Trident Racing 1:46.420 +3.021 3
20. Michael Herck Scuderia Coloni 1:46.493 +3.094 11
21. Pal Varhaug Dams 1:46.641 +3.242 12
22. Charles Pic Barwa Addax Team 1:46.991 +3.592 8
23. Davide Valsecchi Team AirAsia 1:47.015 +3.616 11
24. Jolyon Palmer Arden International 1:47.269 +3.870 12
25. Julian Leal Rapax 1:47.608 +4.209 10
26. Esteban Gutierrez Lotus ART 1:49.251 +5.852 2