Mercedes Software Bug Hit Russell Harder Than Antonelli

Mercedes have traced George Russell's recent top-speed deficit to a software bug in the power unit code — and deputy technical director Simone Resta confirmed it hurt Russell significantly more than team-mate Kimi Antonelli. The fix, Resta says, is locked in for the Hungarian Grand Prix.

Russell's Mysterious Top-Speed Problem

Russell and his engineers spent weeks puzzled by the gap in straight-line pace relative to Antonelli at Silverstone and Spa-Francorchamps. The Briton tried adjusting his driving style. Nothing worked. The root cause turned out to be a fault in the energy distribution software shared across all Mercedes-powered cars. Spa, one of the highest power-delta circuits on the calendar, exposed it fully.

The aggravating factor was Russell's older power unit. Antonelli was running a fresher powertrain, which naturally masked the bug's impact on his side of the garage. As Resta put it, the software was the same for every car, but it hit Russell harder given his more worn unit. That asymmetry is set to correct itself when Mercedes fits Russell a newer power unit in the coming rounds.

How Older Power Unit Masked the Bug

The consequences at Spa were severe. Russell was swallowed on the Kemmel Straight on lap one of the Belgian Grand Prix, then spun into the gravel by Lewis Hamilton — a retirement that cost him dearly. He now sits third in the championship standings on 154 points, 50 behind Antonelli's 204 and five behind Hamilton's 159.

Resta credited Russell for pushing the team to find the answer: the driver challenged and highlighted the problem, the team eventually nailed it. That is how good partnerships are supposed to work. Budapest is where the proof arrives — follow all the action at our race centre.