Nicholas Tombasis on how the ADUO system works

      FIA's Director of Single-Seater Racing, Nicholas Tombazis, spoke about how the ADUO system works, allowing manufacturers to upgrade previously homologated power units. During specific periods of each season from 2026 to 2030, the FIA will monitor the performance of the internal combustion engine (ICE) that is part of the power units and will calculate a performance index taking into account torque, RPM, MGUK power, and weight. Since the ADUO index only pertains to the ICE, it does not reflect the efficiency of the entire power unit but will allow for compensation of any lag. A manufacturer whose ICE lags behind the most efficient by at least 2% will receive ADUO status.

      Question: How does ADUO work in the context of the Financial Regulations regarding power unit manufacturers? Nicholas Tombazis: It is important to clearly understand that ADUO is not a mechanism for equalizing power and efficiency. A team or manufacturer will not be granted permission for greater fuel consumption or ballast weight. A power unit manufacturer that meets the ADUO criteria during the verification period will have the opportunity to upgrade their engine. This task should not be underestimated – the manufacturer will still have to create a better engine to win. It is not a panacea or bonus points for those who lag behind. It simply provides freedom of action for the development of the power unit within the framework established by the Technical Regulations.

      The impact of ADUO on manufacturer expenses is outlined in the regulations, which define the benefits granted to manufacturers lagging by 2% or more from the best power unit's performance during each ADUO period. In particular, each manufacturer lagging by 2-4% will receive benefits of up to $3.0 million. For a lag of 4-6% – up to $4.65 million, for 6-8% – up to $6.35 million, for 8-10% – up to $8 million. For manufacturers with a lag of 10% or more, in addition to the allocation of funds for each ADUO period of up to $11 million, there is an additional opportunity, only for the 2026 season, to allocate up to $8 million from the future periods' cost limit to support development activities.

      Question: When do the monitoring periods take place, and has the calendar update affected them? Nicholas Tombazis: Article 4.2 of Appendix C5 of the 2026 Technical Regulations divided the season into three periods during which the performance of internal combustion engines will be analyzed to determine whether a manufacturer can claim ADUO. These 3 periods cover races 1-6, 7-12, and 13-18, respectively. However, the first period, covering the Grands Prix of Australia, China, Japan, Bahrain, Saudi Arabia, and Miami, was disrupted due to events in the Middle East. As a result, the period has been adjusted and now consists of the first five races of the season (Australia, China, Japan, Miami, and Canada). The results will be announced no later than two weeks after the Canadian Grand Prix. The second period will cover races 6 to 11 (from Monaco to Hungary), and the third will cover races 12 to 18 (Netherlands to Mexico). After the results are announced, power unit manufacturers eligible for ADUO will receive a notification detailing their quota – and will be able to implement updates at the next race.

      Question: How do manufacturers qualify for ADUO? Nicholas Tombazis: As stated in Article 4.3 of Appendix C5, a manufacturer whose ICE performance index lags behind the best-performing ICE by 2-4% will be entitled to one additional upgrade in the current season and one additional upgrade in the next season. Manufacturers whose lag is at least 4% will be entitled to two additional upgrades in the current season and another two in the next. However, manufacturers who do not qualify for ADUO after the first two periods will not be able to claim ADUO after the final period in the same season.

      Question: Are these upgrades cumulative? Nicholas Tombazis: ADUO upgrades do not accumulate during the season and will only be provided the first time a manufacturer is recognized by the FIA as eligible for them. However, upgrades for the next season can still be used if the team meets the ADUO thresholds in the following season. For example, after the 2026 Canadian Grand Prix, manufacturer X shows results below 4% from the leader and receives ADUO for two upgrades in 2026 and two in 2027. If after Period 1 of 2027 it again shows a lag of less than 4% and receives ADUO in the form of two upgrades for 2027 and two for 2028, it is allowed to implement four upgrades in 2027 (two from ADUO for 2026 and two from ADUO for 2027).

      Question: Can upgrades be carried over from season to season? Nicholas Tombazis: No. Any upgrade not used by the last event of the season will be forfeited. For example, if after the Canadian Grand Prix it qualifies for one upgrade in 2026 and one in 2027, it must present the 2026 upgrade by the end of the season, otherwise, it will lose that opportunity. The upgrade for 2027 will remain valid.

      Question: Which components can manufacturers upgrade? Nicholas Tombazis: Although the ICE serves as the criterion for granting ADUO, upgrades can be made to a wide range of components, including ICE parts, exhaust systems, turbines, valves, electrical components and sensors mounted on the ICE, recovery systems (and associated cooling systems), MGU-K, and the vehicle's electronic control unit, as well as certain hydraulic functions, fluids, and ballast.