David Coulthard believes the FIA could have avoided Formula 1’s latest engine controversy with tighter wording in its regulations.
The new era of Formula 1, encompassing both chassis and power units, has been met with immediate controversy as reports surface alleging that Mercedes and potentially Red Bull Powertrains, discovered a loophole in the engine regulations concerning compression ratio.
David Coulthard criticises FIA over compression ratio loophole
This year’s regulations reduced the compression ratio from 18:1 to 16:1 when measured under “ambient” conditions. However, it’s been claimed that Mercedes found a way to achieve a ratio of 18:1 once the engine reached operating temperature. This was possible since the initial measurement was taken in static conditions. Reaching 18:1 while running at temperature provided a performance advantage and improved fuel consumption.
The potential advantage gained by Mercedes prompted rival power unit manufacturers – Ferrari, Audi, Red Bull Powertrains and Honda – to seek a resolution, leading the FIA to initiate an e-vote.
The result of that vote was a change in the regulation’s wording. The FIA announced that the temperature criteria for measuring power unit performance must now include a measurement at 130 degrees Celsius, in addition to the original ambient-temperature testing. This change will take effect mid-season.
Article C5.4.3 of the technical regulations now reads:
– No cylinder, as referred to by C5.1.3, of the Engine may have a geometric compression ratio higher than 16.0, measured in the following conditions:
– Until 31 May 2026: when the Engine is at ambient temperature
– From 1 June 2026 to 31 December 2026: when the Engine is at ambient temperature as well as when the Engine is at 130degC. Any component, assembly, mechanism, or integrated arrangement of components that is designed or functions to increase the compression ratio in operating conditions beyond 16.0 is prohibited.
– The procedure which will be used to assess compliance with this article must be defined by each PU Manufacturer according to the instructions detailed in the document FIA-F1-DOC-042. This procedure must be approved by the FIA Technical Department and included in the PU Manufacturer homologation dossier.
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After weeks of discussion and behind-the-scenes meetings, former F1 driver David Coulthard believes the FIA could have prevented the entire situation by clarifying the regulations from the outset.
“Here’s the thing,” he said on the Up to Speed podcast. “The FIA, the governing body of Formula 1, has a relatively small team of around 20 people writing the rules, while the F1 teams employ hundreds. That’s why the loophole wasn’t initially identified and then closed.”
“If the regulation makers had a better understanding of the operational window of a Formula 1 car…
“An operational window isn’t a car sitting in a garage at ambient temperature. It’s out on the track, with engine temperatures at 110°C and brakes exceeding 1000°C. That’s where the rules and regulations should be designed around.”
The FIA consistently faces challenges when drafting new regulations, as teams dedicate significant resources to finding and exploiting any ambiguity. This has been a hallmark of F1’s history and, some argue, is a testament to the sport’s competitive spirit.
Williams team principal James Vowles, whose team is powered by Mercedes engines, spoke to PlanetF1.com and other media during pre-season testing, stating: “We as a sport have to ensure this remains a meritocracy where the best engineering outcomes are rewarded, not penalized. I’m sure other teams are frustrated they couldn’t achieve what Mercedes did, but we need to protect the principle that the best engineering solution wins.”
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