1991
SEASON

Drivers and constructors

The following teams and drivers competed in the 1991 FIA Formula One World Championship. Footwork Ford

Regulation changes

On the topic of safety, the FIA would perform more stringent testing of the survival cell , including seat belts , fuel tanks and rollbar . The minimum weight (without driver) was raised from 500 kg (1,100 lb) to 505 kg (1,113 lb).

Race 1: USA

The season started off at the Phoenix street circuit that had a modified layout to make it more of a challenge to drivers. Senna took pole ahead of Prost, Patrese, Mansell, Piquet and Alesi. At the start, Senna and Prost maintained their places while Mansell sliced ahead of Patrese and Piquet lost out to Alesi and Berger. The order at the end of lap 1 was: Senna, Prost, Mansell, Patrese, Alesi and Berger. Early on, as Senna was pulling away from Prost, Alesi got past Patrese for fourth. However, Patrese repassed him on lap 16 and closed up on Mansell. He attacked on lap 22 but shot into an escape road and rejoined behind Alesi and Berger. He quickly closed up on them with Berger attacking Alesi but unable to pass. Patrese passed Berger on lap 34. On the next lap, Mansell's gearbox failed and soon afterward, on lap 36, Berger had fuel pump trouble, which forced him to retire. Patrese then passed A... Patrese didn't last much longer, his gearbox failing and then the stationary car was hit by Roberto Moreno, forcing both of them out. Piquet, who did not stop, was passed by Alesi for second with Prost taking fourth off Stefano Modena soon after. Alesi was having gearbox troubles and was holding back Piquet as Prost began to attack both of them. On lap 70, Piquet passed Alesi and Prost followed him through. Prost then shifted sides getting ahead of Piquet as well. Modena passed Alesi for fourth ...

Race 2: Brazil

The field traveled to Brazil and Senna pleased his fans at the Interlagos circuit in his home city of São Paulo by taking pole at his home track ahead of the two Williams cars of Patrese and Mansell who were in front of Berger, Alesi and Prost. At the start, Senna took off and Mansell got by Patrese while Alesi got by Berger and Piquet got ahead of Prost. The order was: Senna, Mansell, Patrese, Alesi, Berger and Piquet. Mansell began to attack Senna but could not pass. Senna then slowly pulled away from Mansell who had a slow pit stop on lap 22. He stayed second after the stops but 7 seconds behind Senna, the major change as a result of the stops was that Piquet who did not stop was third and that Berger and Prost had got by Alesi. Berger blasted past Piquet soon afterward as Mansell began to catch Senna. Mansell was closing in but had to stop on lap 50 with a puncture. He charged back towards Senna who was experiencing gearbox troubles. However, it was Mansell's gearbox which ironically gave way on lap 60. Patrese was having the same problem but still running in second and Berger was having trouble with a sticking throttle. It began to rain and Prost passed Piquet for fourth. The top three struggled with the wet condition...

Race 3: San Marino

At Imola , Senna took his 55th pole position ahead of Patrese, Prost, Mansell, Berger and Modena. It rained as they were approaching the start and Prost spun off on the parade lap and was out. At the start, Patrese got ahead of Senna while Mansell had gearbox problems and retired after being hit by Martin Brundle 's Brabham . The order was: Patrese, Senna, Berger, Modena, Alesi and Nakajima. Patrese pulled away but pitted on lap 10 with a misfire and rejoined several laps down. On lap 16, Nakajima retired from fourth with transmission failure. After the stops, Senna stayed ahead of Berger while Moreno got fourth from Pierluigi Martini. Soon afterward JJ Lehto passed Martini to take fifth. At the front, the gap between Senna and Berger was stable. Modena retired on lap 42 with transmission troubles, promoting Moreno to third which he held only for eight laps when Lehto passed him. On...

Race 4: Monaco

Senna took another pole in Monaco with Modena a surprising second ahead of Patrese, Piquet, Mansell and Berger. At the start, Berger hit Piquet and Piquet was out while Berger dropped to the back. The order was: Senna, Modena, Patrese, Mansell, Prost and Moreno. With overtaking hard on the Monaco streets, there were no changes until Prost got past Mansell on lap 30. By now, Senna was over 10 seconds ahead of Modena, who was holding up Patrese. Soon afterward, Alesi passed Moreno for fourth and pulled away. Meanwhile, Nakajima in the other Tyrrell further down had spun off the track after making contact with Martini's Minardi on lap 35. On lap 43, Modena's engine blew in the tunnel and this blocked Patrese, who spun off into the wall and both were out, a... Mansell was putting pressure on Prost, who had trouble with a loose wheel, and made a daring move through the chicane on lap 63 to take second and then really started flying with fastest lap after fastest lap before Prost eventually set the fastest lap on lap 77 (14 laps after his pit-stop as he was a lap down in 5th place). Soon afterward, Prost was forced to stop to change the wheel and dropped down to fifth. Senna took his fourth win in four ahead of Mansell, Alesi, Moreno, Prost and Emanuele...

Race 5: Canada

At the Circuit Gilles Villeneuve in Montreal, the Williams cars were 1–2 in qualifying, Patrese on pole ahead of Mansell, Senna, Prost, Moreno and Berger. At the start, Mansell got ahead of Patrese while Berger slipped past Moreno. It was Mansell leading from Patrese, Senna, Prost, Berger and Moreno. On lap 5, Berger retired with battery troubles but Moreno could take fifth only for 5 more laps before he spun off into retirement. Mansell and Patrese were pulling away from Senna while there was a battle for fourth between Prost, Alesi and Piquet. On lap 26, Senna retired with alternator troubles and two laps later Prost was out with a failed gearbox. Alesi was third but on lap 35, his engine expired. This put Mansell in front of Patrese, Piquet, Modena, Andrea de Cesaris and Ivan Capelli . Patrese had to pit with a puncture and rejoined behind Piquet. He then had gearbox troubles and was passed by Modena as Capelli spun o... On the last lap, Mansell waved to the crowd, and then he let his car's revs drop too low and stalled the Renault engine. This left a delighted Piquet to take his last career win ahead of Modena, Patrese, de Cesaris, Bertrand Gachot and Mansell who was classified sixth.

Race 6: Mexico

The extremely bumpy Hermanos Rodriguez Autodrome in Mexico saw a number of incidents during practice, including Senna crashing at the very fast Peraltada while trying to take it a bit faster than usual and his car overturned when it hit the tire barrier. Senna had come to Mexico City with a head injury that he got while jetskiing in Brazil, and had been critical of the dusty circuit's condition all through the weekend. Williams took 1–2 in qualifying with Patrese ahead of Mansell, Senna, Alesi, ... Berger's engine failed on lap 6 and soon afterwards Patrese passed Senna and set off after Mansell. Modena then began to drop back. Patrese passed Mansell and then both Senna and Alesi had a go at the Englishman with Alesi spinning and dropping back to seventh. Patrese then began to pull away from Mansell who was holding up Senna. Meanwhile, Alesi passed Moreno and then de Cesaris as Mansell pulled away from Senna. He closed the gap to Patrese to 1.2 seconds before Patrese increased his pace and... Alesi's clutch failed on lap 43 and Piquet had wheel bearing troubles two laps later and thus Gachot was fifth. He held it until he spun off on lap 52. At the front, Patrese won with Mansell making it a Williams 1–2 ahead of Senna, de Cesaris, Moreno and Éric Bernard .