FIA bans Mercedes engine trick deemed 'not so safe' by driver

Mercedes driver Kimi Antonelli has publicly acknowledged that a now-banned engine deployment trick used by his team was "not so safe," after it left him a vulnerable "sitting duck" on track. The FIA has issued a new technical directive closing the loophole, which was exploited by Mercedes and Red Bull Powertrains to gain a qualifying advantage at the cost of post-lap electrical failure.

Why it matters:

This intervention highlights the ongoing cat-and-mouse game between F1 teams seeking performance loopholes and the FIA's role in maintaining sporting integrity and, crucially, on-track safety. The trick created dangerous speed differentials, putting drivers completing a fast lap at risk of encountering a nearly powerless car coasting slowly on the racing line. The FIA's swift action reinforces that safety concerns will override marginal performance gains.

The details:

• The trick exploited a rule designed for emergencies, allowing teams to shut down the MGU-K (Motor Generator Unit-Kinetic) to prevent component damage.
• By triggering this shutdown just before a qualifying lap ended, teams could avoid a mandatory 50kW per second power reduction on the approach to the finish line, gaining an estimated 50-100kW advantage.
• The severe trade-off was a mandatory 60-second MGU-K shutdown period after the lap, leaving the car without hybrid power and drastically slow on track.
• Antonelli experienced this firsthand in Japan, calling the experience "stressful" as he rolled slowly through the high-speed Suzuka esses with a non-responsive car.
• The Williams of Alex Albon, also Mercedes-powered, stopped on track during Suzuka practice due to complications from the procedure.
• Ferrari reportedly raised safety concerns with the FIA, leading to the new technical directive that insists the mechanism be used only for genuine emergencies.

What's next:

With the loophole officially closed, teams must revert to the standard power deployment rules. The focus now returns to conventional car development, with Antonelli leading the championship heading into the Miami Grand Prix. This incident serves as a clear reminder that while innovation is central to F1, the governing body will act decisively when a performance exploit crosses into the realm of unacceptable risk.