Before then the Tech 1 man hadn't been a factor at all near the front of the field, but on his final run he put together a short sequence of impressive laps, going even faster as the session entered its final minute.
Carlin's Kevin Magnussen improved at around the same time as Bianchi to go second, as both deposed morning pace-setter Antonio Felix da Costa.
The Red Bull-backed driver, who led the way in a wet first session of the day, eventually finished the afternoon fourth quickest as Fortec's championship leader Robin Frijns made a last-minute jump up the order to take third.
Da Costa's Arden Caterham team-mate Alexander Rossi ended the day with the fifth best time after he had enjoyed a brief spell at the top before da Costa and Marco Sorensen kicked off the late-session excitement with just over a quarter of an hour to go.
Sorensen, who briefly led the way before da Costa deposed him, was down to sixth by the end.
While title frontrunners Bianchi and Frijns opted for a quick run at the end of the day, the other man in the championship fight - Sam Bird - didn't follow their lead and ended proceedings in 14th place.
Of the championship's three newcomers this weekend, local hero Tamas Pal Kiss had the best day as he went 12th quickest. GP3 title contenders Daniel Abt (23rd) and Aaro Vainio (25th) had more low-key starts to their FR3.5 careers.
Practice one:Pos Driver Team Time Gap 1. Antonio Felix da Costa Arden Caterham 1m50.543s 2. Marco Sorensen Lotus 1m50.823s + 0.280s 3. Sam Bird ISR 1m51.024s + 0.481s 4. Robin Frijns Fortec 1m51.207s + 0.664s 5. Mikhail Aleshin RFR 1m51.215s + 0.672s 6. Arthur Pic DAMS 1m51.320s + 0.777s 7. Kevin Magnussen Carlin 1m51.352s + 0.809s 8. Kevin Korjus Lotus 1m51.633s + 1.090s 9. Zoel Amberg Pons 1m51.706s + 1.163s 10. Walter Grubmuller P1 1m51.970s + 1.427s 11. Nico Muller Draco 1m52.055s + 1.512s 12. Alexander Rossi Arden Caterham 1m52.133s + 1.590s 13. Jules Bianchi Tech 1 1m52.266s + 1.723s 14. Nick Yelloly Comtec 1m52.393s + 1.850s 15. Daniil Move P1 1m52.819s + 2.276s 16. Tamas Pal Kiss BVM Target 1m52.885s + 2.342s 17. Lucas Foresti DAMS 1m53.165s + 2.622s 18. Will Stevens Carlin 1m53.258s + 2.715s 19. Jake Rosenzweig ISR 1m53.370s + 2.827s 20. Andre Negrao Draco 1m53.648s + 3.105s 21. Carlos Huertas Fortec 1m53.659s + 3.116s 22. Daniel Abt Tech 1 1m53.977s + 3.434s 23. Yann Cunha Pons 1m54.517s + 3.974s 24. Vittorio Ghirelli Comtec 1m54.744s + 4.201s 25. Aaro Vainio RFR 1m54.975s + 4.432s 26. Nikolay Martsenko BVM Target 1m56.379s + 5.836s Practice two:Pos Driver Team Time Gap 1. Jules Bianchi Tech 1 1'29.086 2. Kevin Magnussen Carlin 1m29.186s + 0.100s 3. Robin Frijns Fortec 1m29.652s + 0.566s 4. Antonio Felix da Costa Arden Caterham 1m29.661s + 0.575s 5. Alexander Rossi Arden Caterham 1m29.668s + 0.582s 6. Marco Sorensen Lotus 1m29.836s + 0.750s 7. Nick Yelloly Comtec 1m29.865s + 0.779s 8. Arthur Pic DAMS 1m29.898s + 0.812s 9. Nico Muller Draco 1m29.958s + 0.872s 10. Will Stevens Carlin 1m29.964s + 0.878s 11. Daniil Move P1 1m30.001s + 0.915s 12. Tamas Pal Kiss BVM Target 1m30.152s + 1.066s 13. Carlos Huertas Fortec 1m30.185s + 1.099s 14. Sam Bird ISR 1m30.189s + 1.103s 15. Andre Negrao Draco 1m30.294s + 1.208s 16. Kevin Korjus Lotus 1m30.384s + 1.298s 17. Walter Grubmuller P1 1m30.429s + 1.343s 18. Zoel Amberg Pons 1m30.521s + 1.435s 19. Jake Rosenzweig ISR 1m30.524s + 1.438s 20. Vittorio Ghirelli Comtec 1m30.772s + 1.686s 21. Lucas Foresti DAMS 1m30.877s + 1.791s 22. Mikhail Aleshin RFR 1m30.888s + 1.802s 23. Daniel Abt Tech 1 1m31.314s + 2.228s 24. Yann Cunha Pons 1m32.010s + 2.924s 25. Aaro Vainio RFR 1m32.698s + 3.612s 26. Nikolay Martsenko BVM Target 1m35.689s + 6.603s
The 2015 Formula Renault 3.5 season will be notable for being the last with the French company's backing but also produced a worthy champion in Oliver Rowland. PETER MILLS evaluates this year's crop of drivers
Last year's field was extraordinary and hard to match, but the Formula Renault 3.5 grid will still have plenty of talent this season. Glenn Freeman runs through the field ahead of this weekend's season opener
Landing the Fortec seat that took rising star Robin Frijns to the 2012 FR3.5 title was already a good sign for Stoffel Vandoorne. Then McLaren took him under its wing. Peter Mills tells Vandoorne's story so far