La Journée Test des 24 Heures du Mans 2015 s’est déroulée dans des conditions météo instables. Brendon Hartley (Porsche/Michelin N°17) a profité d’une courte période de beau temps pour réaliser le meilleur temps devant la Porsche 919 Hybrid N°19 et les Audi N°7 et N°8. Aston Martin a dominé les catégories LM GTE.
Après la pause-déjeuner au cours de laquelle la pluie avait cessé, les teams ont hésité à renvoyer leurs autos en piste en début de seconde session. Etrange…
Dix minutes après le drapeau vert, la pluie est réapparue sur Le Mans, et bizarrement, c’est à ce moment-là que plusieurs prototypes LM P1 ont pris la piste ! Peut-être voulaient-ils évoluer sur un circuit complètement mouillé au lieu d’une piste mi-sèche, mi-humide qui n’est jamais très intéressante pour une séance de développement.
La CLM P1/01 du Team ByKolles n’a pas repris la piste cet après-midi après la rupture d’un élément de carrosserie arrière ce matin (pas de pièce de rechange). De son côté, la Ligier JS P2 N°34 – la plus rapide des LM P2 ce matin – a dû subir un changement de moteur. L’opération a duré un peu moins de trois heures.
La pluie s’est ensuite calmée et l’asphalte a commencé à sécher. Durant ces quelque trois-quarts d’heure, Porsche, Audi et Toyota se sont relayés en haut des classements, alors que Nissan est resté concentré sur son travail de développement.
Au volant de la Porsche 919 Hybrid/Michelin N°17, Brendon Hartley a signé le meilleur tour en 3min21s061, battant la pole position 2014 de 0s728. Ce chrono laisse à penser que la pole 2015 pourrait se jouer en moins de 3min20s. Pour mémoire, le record du circuit actuel est de 3min18s513 (Sarrazin, Peugeot/Michelin, 2008).
Peu après la performance de Brendon Hartley, la pluie est revenue, prohibant toute amélioration. Les teams se sont alors concentrés sur leur roulage et les rookies sur leurs 10 tours obligatoires.
Le classement a changé dans toutes les catégories. Aston Martin/Michelin s’est hissé en tête des catégories LM GTE Pro et Am avec, respectivement, la N°97 (3min58s069) et la N°98 (3min59s338) qui a signé le 3e meilleur temps toutes GTE confondues.
En LM P2, l’Oreca03-Nissan N°48 Murphy Prototypes a conclu la journée Test en tête (3min42s405). Sept châssis différents occupent les sept premières places.
Mixed, predominantly rainy weather spoiled the party at the 2015 pre-Le Mans Test Day, but it did give teams a potentially valuable chance to experience the French circuit in wet conditions. During a brief dry spell, Brendon Hartley (N°17 Porsche/Michelin) even managed to beat the best qualifying lap of 2014, suggesting some lightning-quick times when teams return to La Sarthe on June 10. The N°19 Hybrid 919 made it a one-two result for the German make, ahead of the N°7 and N°8 Audi/Michelins. Aston Martin/Michelin topped the LM GTE Pro and Am timesheets.
After the hour-long lunch-break, during which time the morning’s rain eased off, the teams seemed bizarrely reticent to send their cars back out for the start of today’s second four-hour session, even though the track was practically all-dry at this time.
Ten minutes after the green light, however, the rain worsened again and, strangely, this was when several LM P1 teams chose to go out. Perhaps they were encouraged by the fact that the conditions were entirely wet again instead of hovering between wet-and-dry, which isn’t ideal for useful set-up work. That said, it served to provide handy information about slick, hybrid/intermediate, full wet tyre-windows!
One car that didn’t reappear was the N°4 CLM P1/01 (ByKolles) which suffered rear deck damage this morning and had no spares. Meanwhile, the N°34 Ligier JS P2 – the morning’s fastest LM P2 runner – had its HPD engine changed after a late problem in session one. The swap took a little less than three hours.
In keeping with the day’s pattern, the rain then eased off and the asphalt started to dry again, signalling the start of three-quarters of an hour of tumbling lap times. This saw Porsche, Audi and Toyota all take turns at the top of the timesheet, while Nissan was content to continue ticking tasks off its long job list.
The phase culminated with Hartley’s performance in the N°17 Porsche 919 Hybrid/Michelin on the one-hour mark. The New Zealander lapped the 13.629km Circuit de la Sarthe in 3m21.061s which was not only today’s fastest time but also 0.728s quicker than the 2014 pole-winning time (Nakajima, Toyota).
This sort of lap certainly suggests that the scrap for this year’s grid positions might take us well under the 3m20s threshold. For memory, the record for the track in its current form (more or less) is 3m18.513s (Sarrazin, Peugeot, 2008).
Soon after Hartley’s effort, rain swept in again and the remainder of the afternoon was marked by further showers as teams did their best to gather useful data and complete their ‘rookie’ laps as necessary.
Meanwhile, compared with the morning, the lead changed hands in all the other classes, with Aston Martin/Michelin gaining the upper-hand in LM GTE Pro and Am. The British outfit overturned Ferrari’s earlier domination of the latter with its N°98 Vantage V8 (Dalla Lana/Lamy/Lauda, 3m59.338s) which ended up on the day’s GTE podium! The fastest Pro car was the N°97 Aston (Turner/Mucke/Bell, 3m58.069s) which edged nine-hundredths of a second clear of the second-placed N°64 Corvette C7.R.
The day’s LM P2 honours ended up in the hands of the N°48 Oreca03R-Nissan (Murphy Prototypes, 3m42.405s).