Mercedes will run its controversial new front wing package on both cars at the Autódromo Hermanos Rodríguez this weekend.
The front wing package raised eyebrows when it was displayed in the pit lane over the weekend, with questions being asked over its legality due to the winglets that connect to the flap elements.
Trackside Engineering Director, Andrew Shovlin, has now confirmed that it wasn't ran in Austin due the team only having one specification of the wing and no spare.
Instead of running the risk of it being damaged during qualifying and having to make a specification change in Parc Ferme which would've resulted in a grid drop, Mercedes elected to keep it on show in the pit lane.
“The reason we didn’t run it in Austin was because we only had one of those parts so if we damaged it during qualifying it would have meant the car that damaged the wing had to start from the back," confirmed Shovlin, in the team's race debrief video.
"Also with a very busy programme we had the tyre test in FP2, we didn’t actually have the time to evaluate.
"We have more of those parts available in Mexico, we will run that on the Friday, we will check if it is all working as expected and the plan at this stage is to race that wing.”
Mercedes to argue with the FIA over its legality
The front wing was part of the last major upgrades brought by Mercedes for the W13, with Technical Director Mike Elliott saying that it exploits a key area of the regulations that are up for debate with the FIA.
"I think there's fuss about it because in the regulations, it talks about the primary use being for mechanical or measurement purposes," Elliott told media, including RacingNews365.com.
"Clearly there's a secondary benefit of an aerodynamic design that's in there as well.
"We will decide whether we want to argue that one or not, it's actually not worth a huge amount. The detail looks interesting, but it's not the big thing on the front wing."
Initially the design was said to be deemed legal by the FIA, after the team went through the normal review process of submitting their CAD drawings.
Elliott explains the dispute is down to the specific wording of the regulation relating to the design, but initially didn't think the team would contest it.
"We go through a CAD review process with the FIA before we come to the circuit, that happens all the time.
"It was something that was seen there and then they came back and said, we're not so sure about this. So that process, I think works.
"If you look at the regulations there is about 40 incidences in the regulations of 'sole purpose' and in this case it doesn't say 'sole purpose' it says 'primary purpose' [referring to the design].
"I think there's an argument to be had, whether we want to have it as another question."
With Shovlin confirming they will run the new specification at Mexico, it seems Mercedes feel they have a case to argue.
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