The W05 was designed under the direction of Bob Bell, Aldo Costa, Geoff Willis, Loïc Serra, and several other senior engineers at Brackley. Its name followed the convention established in 2010, representing the fifth Formula One car Mercedes had constructed as a works team. The "Hybrid" suffix was added to acknowledge the fully integrated hybrid power unit mandated by the 2014 technical regulations, which required teams to incorporate Motor Generator Units for both heat (MGU-H) and kinetic energy (MGU-K) recovery.
The chassis retained the silver-grey livery the team had carried since 2010. The car's most distinctive technical advantage lay in the PU106A power unit: by splitting the turbocharger and compressor to opposite ends of the engine, Mercedes freed up packaging space and improved airflow management in ways rivals could not immediately replicate. Lewis Hamilton described it as the best car he had ever driven.
The W05 made its race debut at the 2014 Australian Grand Prix, where Rosberg won by 27 seconds — a signal of the car's overwhelming pace. Hamilton then won the Malaysian, Bahrain, Chinese, and Spanish Grands Prix in succession. Through the first five races, the car qualified on pole for every round, led every racing lap, won every race, and set every fastest lap — a level of early-season dominance unprecedented in Formula One history.
The only victory Mercedes did not take through the first half of the season was the Canadian Grand Prix, where Red Bull's Daniel Ricciardo won after both Mercedes MGU-K units failed. Williams driver Felipe Massa also denied Mercedes a front-row lockout in Austria. These were isolated exceptions: across the full season, the W05 took sixteen wins (eleven for Hamilton, five for Rosberg), eighteen pole positions, twelve fastest laps, twelve front-row lockouts, and eleven 1-2 finishes.
As the season progressed, the Hamilton-Rosberg intra-team battle intensified. A collision at the Belgian Grand Prix resulted in a puncture for Hamilton and damaged front wing for Rosberg. From Singapore onward, Hamilton held the championship lead. Mercedes clinched the Constructors' Championship at the Russian Grand Prix, the sixteenth round of the season. The finale in Abu Dhabi offered double points under a one-season rule; Hamilton won the race and, with Rosberg suffering an ERS failure that relegated him to fourteenth, claimed the Drivers' Championship. It was Hamilton's second title and Mercedes' first Constructors' crown.
At the Malaysian Grand Prix, Mercedes paid tribute to Michael Schumacher, who was recovering from a skiing injury, by displaying special branding on the car. The same race coincided with the disappearance of Malaysia Airlines Flight 370, which the team also acknowledged through livery messaging.
The season produced several statistical landmarks. The opening four races represented the most dominant start to a season in Formula One history. Rosberg's eleven pole positions in a single campaign set a personal record. Hamilton's season total of eleven victories equalled the record for wins in a season at the time by a single driver in a dominant car era.
The W05 launched what would become an eight-year run of Mercedes dominance in the hybrid era, ultimately yielding 81 Grand Prix victories for Hamilton, 20 for Rosberg, and 10 for Valtteri Bottas. Its technical blueprint — the split-turbo layout of the PU106A — remained the foundation of the Mercedes power unit through multiple subsequent championships. By demonstrating how thoroughly the new hybrid regulations could be exploited by a well-prepared team, the W05 set the competitive template for the entire first generation of the turbo-hybrid Formula One era.