MPH: Revealed - the fault behind Mercedes' Belgian GP deployment chaos
This article from Mark Hughes has an interesting analysis on what happened to the Merc cars/engines at Spa. Their theory is there were two software coding errors that led to the deployment issues.
Some excerpts - this one is about what happened in Lap 1:
"Quite understandably, fans and drivers alike were left extremely confused about issues of battery deployment around the Spa-Francorchamps track last weekend. Some were more affected than others, but George Russell’s whole weekend was destroyed by it. Here, we can give the definitive explanation of what was happening out there.
It was a situation made infinitely more confusing by the combination of the nuances of deployment on this most extreme of energy-starved tracks and for Mercedes by two straightforward malfunctions, rooted deep in software errors.
Here’s what happened at the race start: both Mercs have the correct state of charge of their batteries as the lights go out. But as they exit La Source just a few seconds later, both Kimi Antonelli and Russell suddenly have lost between 30-40% of that charge. In how to distribute the electrical energy through the lap, the software algorithm can only work with what charge it has, so it will immediately have reduced the power they each had available on the charge down the hill to Eau Rouge, even though they were still deploying.
Max Verstappen, in second running alongside Antonelli, suddenly realises he may be able to overtake and so uses the overtake button to deploy more, ensuring he gets ahead into Eau Rouge. In that moment, Antonelli has to lift to make room for the Red Bull. In lifting, Antonelli inadvertently resets the system to give a less severe power restriction up the hill and down the Kemmel straight than Russell suffers. This reset allows Antonelli to deploy for longer than Russell down the Kemmel straight, but still for a shorter period than if it had been working fully. Verstappen meanwhile, having used his overtake button, also runs out of deployment early on the straight. So the battery problems on both Mercs have triggered three separate compromises for Antonelli, Verstappen and Russell."
This one talks about qualifying issues for George and Oscar:
"So, was it just that Russell and Piastri had used up more battery energy earlier in their qualifying laps to be as quick as their team-mates up to that point? Used more brakes and needed to accelerate more and the earlier curtailment of deployment was the price? Not fully, no. That scenario is perfectly feasible, particularly on an energy-starved track, and at Silverstone, Russell was braking for 11% of the lap compared to 9% for Antonelli.
But at Spa the more significant shortfall was in the software. There may have been a small element of driver input, but nowhere near enough to account for the gap to their team-mates. That was mainly from a problem deep in the coding which was over-delivering energy early in the lap, meaning it ran out early. It will have helped Russell and Piastri early in the lap but the benefits would be small compared to the penalty inflicted by running out prematurely. Nothing they were doing in the cockpit would have helped significantly."
So it was multiple issues...if it's software I hope it can be fixed via some sort of patch in Hungary 🙏