Banned Mercedes engine trick ‘not so safe’ as FIA issues new technical directive

Mercedes driver Kimi Antonelli has acknowledged that the team’s engine deployment trick banned by the FIA was “not so safe” after it made him a “sitting duck” in Japan.

It comes after F1’s governing body issued a new technical directive to outlaw the trick believed to have been used by cars powered by Mercedes and Red Bull Powertrains engines.

Kimi Antonelli: Mercedes deployment trick ‘not so safe’

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It emerged after the Japanese Grand Prix that Mercedes and Red Bull had found a way to get around mandatory power reductions on the approach to the timing line over a single lap, which normally sees cars reduce energy deployment by 50 kilowatts per second.

Avoiding this ramp-down effect allowed Mercedes and Red Bull to maintain maximum deployment for longer, gaining an advantage of 50-100 kilowatts over competitors whose power was being gradually reduced.

The trick took advantage of a rule allowing teams to shut down the MGU-K after suffering technical problems to guard against component damage.

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The advantage of using the trick came at the cost of a 60-second MGU-K shutdown period, leaving cars without electrical power for up to a minute after completing a fast lap.

This resulted in safety concerns over potentially dangerous speed differentials between cars on hot laps and those limping, with Ferrari reportedly raising the matter with the FIA.

As reported by PlanetF1.com, the FIA issued a new technical directive last week to insist that the mechanism should only be used in emergency situations as originally intended and not for a performance advantage.

Addressing the FIA’s intervention for the first time, Antonelli has admitted that the potential lap time gains by using the trick were not worth the accompanying safety risks.

He told PlanetF1.com and other media outlets: “Obviously, it wasn’t the nicest of feelings.

“Of course, we tried to squeeze every bit of performance. On one side, you can [end up] facing some issues or some unexpected situations.

“I was aware that could have happened, but obviously I didn’t really experience it up until Melbourne and Suzuka.

“First of all, it’s not so safe because, especially at Suzuka, I was a sitting duck at the chicane and the esses, knowing that the track is also not very wide, there’s not a lot of space.

“It was quite stressful, for sure, not being able to do anything, because obviously the car was not responding to any input and I was just rolling very slowly on track.

“It was a stressful moment, but now it’s good to know that obviously we probably won’t face this thing again.

“Also in qualifying, you could easily get a penalty for this.

“You can easily impede someone on a lap and then you can easily get a penalty and that’s not what you want.

“So of course, this comes with giving up maybe a couple of hundredths of a second, so very little time.

“But at least it gives the confidence that this thing is not going to happen again.”

Antonelli is believed to have used the trick for a performance boost in Australia and Japan, where he was seen moving at slow speed through the esses section after a push lap in practice.

Mercedes reportedly opted to refrain from using the trick for the remainder of the Japanese Grand Prix weekend after talks with the FIA and in light of Antonelli’s temporary MGU-K shutdown.

The Mercedes-powered Williams of Alex Albon also stopped on track during practice at Suzuka as a result of complications from the trick.

According to reports, the trick was not used at the second round in China due to the relatively short distance between the final corner and the timing line.

Antonelli leads the world championship by nine points from teammate George Russell ahead of the resumption of the F1 2026 season in Miami next month having won the last two races.

Additional reporting by Thomas Maher

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