The 2015 6 Hours of Silverstone and the Fassler-Jani duel

Audi's No. 7 car won the 2015 6 Hours of Silverstone on 12 April 2015, completing a record-distance 201 laps. The race opened the 2015 World Endurance Championship, and it was settled by a long fight between the leading Audi and the No. 18 Porsche of Neel Jani, which finished 4.610 seconds behind at the flag.

Who won the 2015 6 Hours of Silverstone?

The No. 7 Audi of Andre Lotterer, Marcel Fassler and Benoit Treluyer won, completing a race-distance record of 201 laps. Lieb, Dumas and Jani finished second in the No. 18 Porsche, and the No. 1 Toyota of Buemi, Nakajima and Davidson took third.

The victory was the ninth overall career win for Lotterer, Fassler and Treluyer. It came in front of a crowd of 45,000 at the 5.892 km (3.661 mi) Silverstone Circuit, where the layout has 18 turns.

A record-distance race decided by one lap and a late penalty, with Audi's No. 7 car taking the first WEC win of the 2015 season.

What set the early pace?

Bernhard, Hartley and Webber qualified their Porsche on pole and led for the opening 80 minutes, until a terminal rear drivetrain failure ended their hopes. The team's teammates Lieb, Jani and Dumas inherited first place, and the three drivers then fought an Audi through the field for most of the race.

Webber led into the first corner, and he drove the No. 17 Porsche into the pit lane on lap 44 to retire with a rear drivetrain problem. Lieb then took the outright lead in the sister No. 18 car, while di Grassi and Treluyer moved into second and third.

Forty-one minutes in, a full course yellow came out after Chatin's No. 36 Signatech Alpine lost a wheel, which had been fitted incorrectly, and struck the outside tyre barrier. Chatin was unhurt and boarded an ambulance without aid, and several drivers made their first pit stops under the caution.

How did the race unfold?

In the early laps the overall leaders ran into slower traffic 12 minutes in. Di Grassi was caught out, ran wide and fell to fifth behind Treluyer and Wurz. Derani passed Tandy on the run to Village corner for second in LMP2.

Racing resumed five minutes after the caution with Webber leading his teammate Dumas. Race control noticed that no repairs had been made to the wall at Copse corner, so a second full course yellow was called early in the second hour to allow the work to be done.

That second caution cost the three LMGTE Pro Aston Martins time as they made their pit stops between the green flag and the yellow. Rigon's AF Corse Ferrari took the LMGTE Pro lead because his team was on a different strategy, and Bachler took over the LMGTE Am lead.

Why did Audi and Porsche swap the lead?

Immediately after the restart, Buemi could not use his hybrid boost because the capacitor had no charge. He was then caught off guard as Treluyer overtook him on the outside at Becketts and di Grassi passed him at Vale, which dropped Buemi to fifth overall.

At the 44th lap Webber retired, and Lieb took the outright lead. Treluyer and di Grassi then battled for second in slower traffic, and their pace put them briefly onto the run-off area before they rejoined without losing much time.

Dumas later returned to the overall lead during the next cycle of pit stops. Lotterer then retook it by double-stinting his tyres and stopping only for fuel, a strategy that let him run longer stints than his rivals.

Conway's Toyota was lapping Roda's Corvette at Becketts when Conway mounted the kerb to avoid it. He hit a thin plastic bollard that lodged in the front of his splitter, which altered the car's turn-in, and Davidson then took second overall.

Did the penalties change the result?

Fassler received a 10-second stop-and-go penalty for track limits at the Club corner exit with 18 minutes left, and he took it with 15 minutes to go. He still won by 4.610 seconds, because Jani's push over the final 14 minutes never closed the gap.

Race engineer Leena Gade urged Fassler to push, and he kept the lead. Jani lowered the gap to 12 seconds and reduced it by lapping in the 1:42 range, but the Audi held on to the flag.

Fassler later argued that a fairer outcome would have come had the team been allowed time to weigh the call. Treluyer also expressed frustration over the penalty, but he called the victory a well-deserved reward for the team's winter work.

How did qualifying set the grid?

Webber set a benchmark lap of 1:39.908 in the No. 17 Porsche, and Hartley's 1:39.634 lap in clear air gave the car pole at a two-lap average of 1:39.721. Jani and Dumas started 0.619 seconds behind on the front row, and di Grassi and Jarvis were 0.012 seconds behind them in third.

Dumas attributed his slower pace to an error on his first lap and to traffic on his next attempt. Davidson and Nakajima put the No. 1 Toyota in fourth, although Nakajima lost time behind slower cars late on his lap.

The No. 28 G-Drive pair of Derani and Gonzalez claimed the LMP2 pole at 1:48.021, which was 0.062 seconds clear of the No. 26 car. Howson and Tandy were 1.3 seconds slower in third.

In LMGTE Pro, Thiim and Sorensen in the No. 97 Aston Martin set the fastest qualifying time at 1:59.970, while Stanaway and Rees in the No. 99 car were 0.206 seconds slower in second. In LMGTE Am, Lamy and Dalla Lana took pole in the No. 98 Aston Martin at 2:01.998, which was 0.937 seconds faster than the No. 50 Larbre Corvette.

What happened in practice?

The first practice session was sunny, and di Grassi's No. 8 Audi set the quickest lap at 1:42.291, 0.144 seconds clear of Webber's Porsche. In the second session Treluyer led the day at 1:41.526, and Derani set 1:48.676 to lead LMP2.

The third session was damp at first, and Nelson Panciatici spun his Signatech Alpine into the Stowe gravel trap with 12 minutes to go. Fassler's Audi went faster after some cars ran off the slippery track into Copse, and Lotterer improved on his co-driver's time as a dry line appeared.

How did the LMP2 and Toyota cars start the race?

Tandy made a fast getaway in the KCMG Oreca to take the LMP2 lead from the pair of G-Drive Ligiers. On lap three di Grassi tried to pass Dumas again, but he ended up on the outside at Loop corner, which let Buemi take third.

Treluyer put Buemi under pressure for third overall. Di Grassi retook fifth from Wurz, and Bird retook the LMP2 lead from Tandy at Brooklands on the sixth lap.

Tandy then lost third in LMP2 to Dalziel after a slow in-lap, and the early order in the class changed again within minutes.

Lotterer closed on Conway thanks to fresher tyres and went around him on the inside at Vale to take second. Conway then ran wide at Abbey on worn rubber, and Dumas went past him for fourth.

Makowiecki's No. 92 Porsche took the LMGTE Pro lead when Rigon made the No. 71 Ferrari's second stop and James Calado took over. Rigon's car had been on an alternative strategy at that point, and the No. 71 car finished third in the end.

How did the LMGTE classes duel in the closing hours?

Bruni moved his No. 51 Ferrari into the LMGTE Pro lead early in the third hour, once the No. 92 Porsche of Pilet had suffered a right-front puncture. Rigon closed on his teammate Vilander and tried to pass on the outside at Village corner, without success.

A few minutes later Rigon tried again, passed Vilander and pulled away. The two AF Corse Ferraris then duelled for the class lead, with Bruni blocked by Calado at Brooklands before he passed him on the next lap.

Class results

The third-placed LMP2 car, the No. 30 ESM, failed its post-race inspection because its front and rear underfloor skid planks were under the minimum thickness of 20 mm (2.0 cm). Strakka Racing's No. 42 car was therefore given third place in LMP2.

How did the rest of the field fare?

Several cars suffered damage. Liuzzi's ByKolles sustained floor damage after contact with Dalziel's ESM car, and it needed half an hour of repairs in the garage. Duval's No. 8 Audi had to pit after running onto grass.

Duval's car spent six and a half minutes and four laps cleaning debris from the front of the car. Klien's car went off at Village corner and damaged its radiator, and Tandy's KCMG car was pushed into its garage after a stone punctured its radiator.

How did the LMGTE classes finish?

AF Corse's No. 51 Ferrari of Rigon and Vilander won LMGTE Pro, unchallenged in the final hour. Dalla Lana, Lauda and Lamy won LMGTE Am in the No. 98 Aston Martin, 13.712 seconds ahead of the AF Corse Ferrari of Aguas, Collard and Perrodo.

The No. 91 Porsche of Christensen and Lietz took second in LMGTE Pro. The No. 71 AF Corse car of Bruni and Calado took third after six stops, switching only the left-hand tyres at the final one.

Dalla Lana, Lauda and Lamy took their third successive win at Silverstone.

What did the result mean for the championship?

Lotterer, Fassler and Treluyer led the drivers on 25 points. Lieb, Jani and Dumas were seven back, and Buemi, Davidson and Nakajima sat three further behind. Audi took the early lead of the manufacturers' championship with 35 points, seven ahead of Toyota.

Porsche had 19 points with seven rounds left in the season, and Wurz, Conway and Sarrazin were fourth with 12 points. Duval, di Grassi and Jarvis were fifth with 10 points.

What did the teams and reporters say?

Lotterer said Audi had been under pressure from the first lap and wanted to carry the momentum into Spa. Davidson said Toyota had to double-stint its tyres to stay in contention, and Jani said he trusted Fassler to battle him without contact.

Motor Sport called the Fassler and Jani battle the highlight of the race, comparing the two cars to a Mini Cooper against a Ford Falcon. The Guardian's Giles Richards said Audi had made their point, and NBC Sports' Luke Smith called Silverstone a feast of racing for the start of what looked like the biggest WEC season yet.