Mercedes has revealed that two loose screws on Lewis Hamilton's rear wing led to the element failing its DRS test in Brazil which triggered the Briton's exclusion from qualifying.
In the post-qualifying check by F1 technical delegate Jo Bauer, it was noted that the gap between the two rear wing lower and upper planes exceeded at one point the authorized maximum 85mm when DRS was open.
Bauer subsequently referred the transgression to the stewards who later rules on car #44's exclusion from the qualifying results.
Mercedes was initially at a loss to understand the discrepancy, but the Brackley squad conducted its own investigation into the failure after it received the rear wing back from the FIA.
"We got the rear wing back," explained team boss Toto Wolff. "And, as we thought, it was broken. It broke in qualifying.
"We didn't pass the 85mm slot gap test on the far right side. We passed it on the left, in the middle, but not on the right, by a fraction of a millimetre. And that's fine.
"We weren't allowed to inspect it, nor to make the argument that the part is being broken. And consequently, we found out that two screws became undone in qualifying. And that caused that right side to be irregular.
"And you know, probably, it was even detrimental to the lap time, but it is what it is. It was reported to the stewards, and that is very different to how these things were handled in the past when you were able to patch up things that got broken during parc ferme."
As upset as Mercedes were by the stewards' decision to exclude Hamilton for such a small margin of error, Wolff was eager to close the chapter and move on.
"It's race gone," he said. "We obviously were able to turn it around. I wish that Lewis could have taken more points from the sprint qualifying.
"But that is the past. I think now the rules are in a way reset, and we're going to do the best out of it for the current grand prix and the next ones to come."
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