By Carlo Platella
Mercedes is working tirelessly to fill the Silver Arrow’s gaps. In addition to the lack of load in corners, the difficulties with balance and rebounds in corners, the W15 suffers from an operating window that is too narrow. In Australia on both Friday and Saturday Lewis Hamlton spoke about excellent sensations from the car in the morning sessions, and then worsened significantly in the afternoon, in a time slot in which qualifying and the race took place. After three races, technical director James Allison identifies external temperatures as one of the possible causes.
Stable structure
“Between FP3 and qualifying, almost we have not made any changes to the set-up”, explains Allison, excluding tuning from the reasons behind the sudden change in character of the car from morning to afternoon. “Obviously we had less fuel and we pushed the engine to the maximum, but there were no significant changes to the set-up, because in the last free practices it seemed to us that the car was in a good operating window, as also highlighted by the times”. In Australia Lewis Hamilton concluded the third free practice session in fourth place, just 92 thousandths away from Leclerc’s best time and just ahead of Russell.
“We started to notice a trend on our weekends. There are some moments on the weekend when we are happy with the car, but then everything escapes us in the competitive sessions, i.e. qualifying and the race. The most obvious correlation we notice at the moment is that when the track is hotter, and therefore the tire temperatures also start to rise, we lose competitiveness. Instead, when we performed at our best it was in the cooler sessions.”
The increase in asphalt temperatures brings with it a loss of grip, especially at the rear, shifting the balance of the car towards the front. The dynamics recall a recurring characteristic in Mercedes of recent years, afflicted by a dancing rear end whose instability worsens as temperatures rise. It is no coincidence that the rear was at the center of the 2024 project, as Allison announced at the launch of the W15: “A great deal of attention was paid to improve the unpredictability of the rear axle of the previous car. We have worked hard to ensure that both axles, but especially the rear one, control the tires better than on the W14.”
The next steps
The start of the season gives a picture in which Mercedes still has work to do to improve rear stability. At Brackley, solutions are being studied to optimize the management of tire temperatures in the next Grands Prix, working on set-up. Allison continues: “During the weekend you can devise a work program aimed at rebalancing the tire temperatures in your favor, from the front to the rear. The whole using traditional tuning toolswhich is what we do in the factory with the simulator.”
However, the technical director does not exclude that structural interventions may be necessary, for which it will be necessary to wait for updates: “If at some point you run out of setup options and need to push yourself even further, then at that point it becomes more difficult, because it would mean that there are hidden features in the aerodynamic map you created. Or the characteristics of the suspensions aggravate these particular characteristics and to fix everything well you have to change them”. The races in April will provide important answers if a different tuning strategy will be sufficient to widen the window of use of the W15. However, the risk at Mercedes is that it is not possible to completely remove the defects from the car without reviewing the basic characteristics of the project by distorting the car, an operation that is impossible without breaking the spending ceiling.
