Ferrari believes that Charles Leclerc’s race-ending failure was caused by his qualifying accident but that even revised pre-race checks may not have picked up the terminal fault.
Leclerc qualified on pole position in Monaco but did so after a hefty accident during the closing stages of Q3.
The right-hand-side of Leclerc’s SF21 sustained substantial damage following the crash at the Swimming Pool chicane and Ferrari undertook repairs as permitted under Formula 1 regulations.
It managed to avoid a grid penalty after giving the gearbox, which is always a leading concern in Formula 1 accidents, the all-clear.
But on his way to the dummy grid Leclerc reported a problem and was forced to return to the garage.
Ferrari quickly diagnosed that a left driveshaft failure had occurred and had no choice but to withdraw Leclerc from the race.
Ferrari stressed in the immediate aftermath that the gearbox was not the fault, dismissing suggestions it had been lax in its checks, and took the SF21 to its Maranello base on Monday for further analysis.
It determined that the driveshaft on the rear-left had not been part of its usual pre-race checks owing to the fact that it had never suffered such a problem.
It was also less concerned about the left-hand-side of the car due to the fact that it was the right-hand-side of the car that had sustained the brunt of the impact in the accident.
Ferrari can also not ascertain that pre-race checks would have highlighted the fault due to the different loads placed upon the car when out on track compared to when stationary in the garage, with there having been no apparent external damage to the component beforehand.
Its data suggested that the driveshaft was working properly as the car left the pit lane but then terminally failed when Leclerc navigated his way through Turn 6 on his way to the grid.
The team added that it will nonetheless review its procedures in light of the incident.