Generally, the words ‘porpoising’ and ‘rebound’ have been used interchangeably, both by drivers and by the teams themselves, to refer to the moment when cars hit the ground when reaching high speeds.
However, James Volwes , the strategy director of the Mercedes team, assures that they do not refer to the same phenomenon and that they are generated differently.
Mercedes appeared to have overcome its porpoising issue with the W13 at the Spanish Grand Prix, but Vowles says the issues are highly circuit-specific, with track surface uniformity playing a key role.
The rebound problem was exacerbated by the bumpy Baku track surface, which caused major discomfort for the drivers, especially Lewis Hamilton. The seven-time F1 world champion had a different setup than his teammate, including alternative rear suspension.
“There’s definitely an element [that varies] from track to track and it’s a relationship between how smooth the tarmac is and the layout of the circuit,” Vowles said in a video released by Mercedes.
“I would say that Baku, without a doubt, of the circuits that we have had so far, is at the worst end and, conversely, Barcelona probably at the best end.
“So those two circuits will highlight the strengths and weaknesses of the package. But it’s also worth spending a bit of time explaining porpoising, bouncing and touching the track with a flat bottom, three ideas that are possibly used very much associating them to the same thing, but that they are not at all”.
Vowles noted that, as indicated at the Spanish GP, the team has made progress in controlling porpoising. But in doing so, and being able to run the car lower, rebound has become an issue.
“Without a doubt, in the first few races we suffered from porpoising, and not in Barcelona,” he said. “We’ve put a lot of effort into our package to make sure we’re doing everything we can to resolve it, and I’m sure we’ve made a step forward.”
“In Barcelona the car was stable, robust and we were able to lower it and that’s the key, we managed to create a package where, aerodynamically, we were able to work a lot more with it, we were able to work with the set-up and we were able to lower the cars in terms of ride height. driving to produce performance.
“Now, in Monaco and in Baku, what has unfortunately been discovered is a second problem that was being masked by the first. I’m sure we’ve made a step forward in terms of porpoising, but we clearly have a rebound, and going into They look almost identical on the outside, but there is a subtle difference between the two.
Vowles says that the rebound is simply an action where the car hits the track: “What happens now is that the car is lower, as a result of solving the first problem, but now it hits the plate quite hard, and that’s creating the rebound that you see right now.”
“Again, you try to extract performance by running the car low, but the problem is very different and the bumpier the track is, the more it adds to the effect, which is what we saw in Baku.
“I think what is clear is that we still have a long way to go to learn everything we need to be fighting at the front, but perhaps more importantly you will see the track-to-track variation of performance as “Let’s move forward. For sure Canada will be very different to Silverstone in terms of the performance of our car.”
Vowles acknowledged that the team made life too difficult for its drivers in Baku, while confirming that Hamilton will be fit and ready for this weekend’s race in Canada, despite Toto Wolff expressing concern on Sunday about the night.
“I’m pleased to report that Lewis is here this morning [at the Mercedes factory], I’ve spent a few hours with him and he’s fine, he’ll be back in the car in Montreal,” Vowles said.
“He’s an elite athlete who is going to push the limits of the endurance of himself and the car, and that’s what F1 drivers do, that’s what makes them exceptional.”
“On this occasion, however, we have taken the package and our drivers too far, we have put them in a situation of significant discomfort and we simply cannot do it again.”
“Our drivers are not the only ones who are suffering, you will see in the media a number of comments from various drivers who are equally uncomfortable and in pain. And now we have a responsibility to make sure this does not continue.”
Lewis Hamilton, Mercedes-AMG, after the race in Baku
The team was taken aback by Hamilton’s comment about his “cold seat” in Baku, but after speaking with his driver, Vowles said it was a physical problem rather than a mechanical one.
“What happened is that nothing changed in the car, it just seems like after the amount of hits his back took from the rebound, fundamentally he had a numbness that set in and it seems like the cold was a response to that.
“There was nothing colder about the car, it was just a response [from his body] to the amount of drag and pain he had suffered in the race.