Practice
Practice was delayed on Friday due to fog and problems with the medical helicopter, but did eventually get going. Red Bull started slower but then dominated in the afternoon and again into Saturday as Vettel ran P18-P1-P1 with Webber P8-P2-P2, the drivers commenting there was work to do with the tyres. Ferrari surprised as Alonso went fastest in FP1 with no back problems, but it didn't last as he ran P1-P10-P11 and Massa P7-P12-P17, who commented their car felt good in the morning but not in the afternoon due to change of conditions. Mercedes ran fairly consistently with Rosberg P5-P3-P7 and Hamilton P6-P4-P3, with both drivers pleased at how the tyres were lasting and their potential. Lotus, with last-minute replacement Kovalainen who barely made it to the circuit on time, found a mix of pace as Grosjean ran P11-P8-P5 and Kovalainen managed P13-P5-P13, with the Finn finding it quite comfortable to slot into the team. Sauber found their form again as Hulkenberg delivered P9-P7-P4 and Gutierrez P4-P6-P12, with both drivers feeling it was a productive practice though there was still a bit of balance to find. McLaren looked stronger through Jenson Button as he ran P2-P9-P6 with the departing Perez P12-P13-P8, with the Brit feeling their car was better, though it was spoilt by a three-place grid penalty after he accidently overtook somebody under red flag. Perez' running was reduced by a mechanical issue and he struggled for balance and tyre temperature. Force India only just about managed to scrape into the top ten with Sutil, on his Austin debut, taking P14-P11-P10 while Di Resta was P15-P15-P16, with both drivers completing long runs and Di Resta feeling their result didn't fairly reflect the pace of their car. Torro Rosso sent reserve rookie Daniil Kvyat out for FP1, managing P17, before Vergne took over again to run P17-P18 in FP2 and 3. Ricciardo, future Red Bull prospect, was P16-P14-P15, and neither driver was pleased with the setup or pace of the car, a way away from their top ten target. At Williams, Bottas surprised by going P3-P16-P8 and Maldonado P10-P18-P14, finding an upswing in pace from their new aero parts and exhaust system as both drivers enjoyed themselves, though Maldonado had issues with balance. Caterham again beat Marussia at the back, with Pic running P21-P19-P19 and Van der Garde P20-P20 after reserve driver Rossi took the wheel for FP1, getting P19. Rossi became the first American F1 driver to drive at the Circuit of the Americas, a proud moment, and he enjoyed himself though struggled with tyre temperature. Pic and Van der Garde both had issues with understeer at points and felt the tyres were close, and also that their pace was good compared to the competition ahead. Pic received a five-place penalty however for an unscheduled gearbox change on Saturday morning. Marussia also sent their reserve driver out in FP1, with Gonzalez P22 and completing his session with engine failure. Bianchi took the car back to run P22-P21 in the other two sessions as Chilton managed P20-P21-P22, with Bianchi suffering balance problems and debutant Chilton brake disc failure, though it didn't really hamper his running.