Why gearbox layout could be key to solving the porpoising puzzle:
https://www.formula1.com/en/latest/...ng-the-porpoising.70jyq6WLn2OpvXsoXdlwQE.html
"... It has been pointed out that the four cars with the Mercedes power unit – Mercedes, McLaren, Aston Martin and Williams – are all struggling for pace. Mercedes are around 1s off Ferrari. McLaren a further 0.5s adrift (on average) than that and trailing a couple of tenths behind Alpine. Aston Martin and Williams are the slowest of all.
But we know from GPS analysis that although the Mercedes power unit is slightly down on power to the Ferrari, the deficit accounts only for around 0.15s of lap time. Given that even Mercedes are 1s off the pace, the power unit cannot possibly be the main culprit for the performance shortfall of any of these teams.
If we confine our study just to the three teams which use the Mercedes PU and gearbox (i.e. excluding McLaren), then we also see a correlation with that and the severity of the porpoising issue.
Correlation and causation are not necessarily the same but both Aston Martin and Williams know they could unleash a big chunk of performance, if only they were not having to raise the car away from the porpoising threshold.
The big difference in design could still be causing frustrations for Mercedes
Why would a gearbox cause such an issue? The length of the gearbox casing is a reflection of how a team chooses to package the mechanical components of its car. If we look at the Mercedes, Williams and Aston, we can see that the sidepods and floor intake begin further back than on other cars. This maximises the distance between the front wheels and the sidepods, which is traditionally aerodynamically beneficial.
But to keep the car within the regulation wheelbase limit, this rearward-biased packaging of the radiators and associated apparatus means a short gearbox casing. If we look at the Ferrari and Haas (which share a PU and gearbox) we see that the sidepods are further forward and that much of the cooling apparatus is pushed up towards the front, giving a big, bluff front to the sidepods but allowing the rear bodywork to cut in more extensively.
Looked at from above, it is much more teardrop in shape than the Mercedes, Williams or Aston Martin (below). The Red Bull and AlphaTauri are configured much more like the Ferrari, in this regard, than the Mercedes. As the sidepod volume begins and ends sooner, so the wheelbase is then defined by a longer gearbox casing.
A top-down look at the Mercedes-powered Aston Martin (top) and Haas (below) shows a teardrop profile for the Ferrari-powered car, its cooling apparatus pushed towards the front
What might this have to do with porpoising? There are at least two possibilities:
01. The wider bodywork at the rear may be contributing towards the airflow restriction of the underbody. The more teardrop-shaped upper bodyworks of the others should be able to exert a more helpful airflow over the top of the diffuser, potentially making the underbody tunnels more stall-resistant.
02. Where the stall point is relative to the car’s centre of gravity could affect the severity of the bouncing. The short gearbox layout could be putting that centre of gravity at a really awkward point relative to the stall point of the underbody and inducing a leverage effect.
We should emphasise that none of this is anything other than conjecture and that the answers may in reality be very different. But there is something nagging about the correlation between the three cars using the same layout, and the severity of their bouncing problem."
www.timeslive.co.za
