New 2017 WRC car aerodynamics have proven to have a weak point after only five races have been completed. High speed combined with irregular surfaces lead to frequent damage of aerodynamic package, which has a significant impact on car performance and, most important, can seriously affect safety for both drivers and spectators. Manufacturers were already aware of such a danger beforehand, and new regulations gave them more freedom in the use of appropriate composites, in order to increase aero package reliability. However, it has proved to be insufficient, as lost or damage of such pieces has been too frequent.
M.Østberg/O.Fløene, Ford Fiesta WRC, 2017 Rally of Sweden, 15th.
The first scare was for Mads Østberg in the SS4 of 2017 Rally of Sweden, when he lost his rear wing after a jump. He continued to drive for two other stages before quitting due to the risk of driving without rear downforce at such high speeds. The effect of such a loss was quickly reflected in his times, as he lost an additional 1.2 s/km after losing the wing when compared to his previous pass on the same stages. A poorer car handling is easily visible in the comparison of Mads’ Ford in stages SS4 and SS7 showed in this video, by GalskapMotorsportcom, which can be found at minutes 2:25 (SS4) and 9:38 (SS7), that is, before and after losing the wing. Without it, the Fiesta WRC hardly equals the behaviour of the slowest WRC2 in that corner.
D.Sordo/M.Martí, Hyundai i20 WRC, 2017 Rally of Mexico, 8th
Dani Sordo experienced also the loss of part of his rear wing in the SS9 of Rally of Mexico, as shown in the image above. However, even if he complained of losing some seconds due to the incident, he was able to be first and second in the stages run after damaging it.
C.Breen/S.Martin, Citroen C3 WRC, 2017 Rally of Argentina, 15th.
J.Hanninen/K.Lindstrom, Toyota Yaris WRC, 2017 Rally of Argentina, ret.
Rally of Argentina 2017 has shown that not only rear wings can be affected, and reliability of the other new aerodynamic appendices has been tested. Craig Breen and Juho Hanninen quickly showed that front splitter is very sensitive to rough terrains, and both of them mentioned poorer car handling after damaging it.
S.Ogier/J.Ingrassia, Ford Fiesta WRC, 2017 Rally of Argentina, 4th
T.Neuville/N.Gilsoul, Hyundai i20 WRC, 2017 Rally of Argentina, 1st
Reliability of dive planes and wheel arches was also tested, by Sebastian Ogier and Thierry Neuville, although they did not complain about any side effect after destroying them.
M.Ostberg/O.Floene, Ford Fiesta WRC, 2017 Rally of Argentina, 9th
Rear diffusers were also tested, especially in the multiple water splashes present in the Argentinian stages. Ford showed to have the weakest diffuser support system, as both Mads Østberg and Elfyn Evans reported the loss of their diffuser, in the same water splash. However, while the Swedish was able to keep his pace after losing the diffuser, the Welshman lost around 0.5 s/km with no diffuser, in the same stages. Is it a proof that rear diffuser is more necessary in asphalt stages rather than in rough terrains? We will see in the next rallies, although it is true that rear damages where more important in Evans’ car.
E.Evans/D.Barritt, Ford Fiesta WRC, 2017 Rally of Argentina, 2ond
In any case, this should be one of the priorities for the teams in the design of the new aerodynamic packages for the coming years; they need to be more robust to ensure they are effective in all terrains.
The picture below shows Mads Østberg lost rear diffuser: although there can be identified several attachment points, big holes in both sides seem to be the reason why the diffuser was lost.