Mercedes have explained that an uncovered brake switch caused Lewis Hamilton to lose performance during qualifying in the United States.
Lewis Hamilton qualified in P5 for last weekend’s United States Grand Prix, with teammate Valtteri Bottas taking pole position. It was the now Championship winner’s lowest grid slot of 2019, and Mercedes have since explained why he struggled so much to unlock laptime in the closing minutes of the session.
Speaking in Mercedes’ post-race Pure Pitwall debrief, strategy director James Vowles said an errant switch position compromised Hamilton’s first run in Q3: “During the course of the lap, underneath his right hand, there’s a little rotary and that rotary adjusts the engine braking. Normally it has a guard on it, and what happened is the guard had accidentally been knocked off, and as he went through the lap and every time he turned the steering wheel, he accidentally changed the engine braking and that caused him to lose performance towards the end of the lap. The mechanics spotted it immediately the second the car had come back in but obviously that first run was compromised as the result.”
“Come the second run you would’ve seen everyone went slower, the track in fact had slowed down slightly, small wind change, small track temperature change and Lewis wasn’t now able to compete at the front, ultimately sealing his place as fifth on the grid.”
In the end, Hamilton quickly made up for his slightly lower qualifying position by getting past Charles Leclerc at the start and then passing Sebastian Vettel to move up to P3 before the end of Lap 1. He would go on to lead the race as his one stop strategy played out but would eventually be caught and passed by teammate Valtteri Bottas in the closing stages. Finishing P2, Hamilton’s 18 points were enough to clinch his sixth World Championship.