Mercedes started the 2026 season with dominant performances that secured both the drivers’ and constructors’ championships, but its performance advantage has visibly narrowed toward the end of the year. According to Mercedes technical director James Allison, this convergence was partly caused by the team’s own development choices rather than just rival teams catching up.
Flawed Update 18 Complicated the W17
Speaking on the NU Silver Arrows Radio Show as reported by Motorsport.com, Allison explained that the team’s latest major aerodynamic package introduced unexpected driveability issues. The team brought the package, known as Update 18, to the Sepang track and later added a new front wing in America.
While the package successfully increased downforce, Allison admitted it created an unpredictable handling experience for the drivers. He stated that the updates made the car more of a handful and introduced unexpected performance drops in certain areas.
Weight Advantage Disappeared Over Time
Allison also discussed the factors behind the team’s untouchable speed during the opening rounds of the championship. New 2026 regulations required a 30-kilogram weight reduction across the grid, bringing the minimum chassis weight down to 768 kilograms, a target Mercedes achieved immediately.
Allison revealed that they were likely the only team operating right at the weight limit at the start of the year. He explained that rival competitors had extra weight to lose, which provided them with natural lap-time gains as the season progressed while Mercedes could not benefit in the same way.
As rival constructors eventually shed their excess mass, the competitive field naturally compressed. This effect was compounded by the flaws in Update 18, which made it significantly more difficult to extract maximum pace from the W17.
