Mercedes discovers true cause of Hamilton's lost Australian GP win

Lewis Hamilton saw a potential victory in the season opener snatched from his grasp after rival Sebastian Vettel gained time pitting during a virtual safety car period.

Mercedes was caught out by Vettel's actions because its race strategy software reported that Hamilton was close enough to retake the lead when the Ferrari stopped.

Initial suspicion pointed to a glitch in its race strategy software, but the team has subsequently found that the problem was caused by an offline tool used to calculate delta times between cars staying out on track and those coming into the pits during various safety car phases.

In the latest episode of its Pure Pitwall race debrief, Mercedes trackside engineering director Andrew Shovlin said action was being taken to ensure the situation never happened again.

"The issue isn't really with the race strategy software that we use," he explained.

"It was an offline tool that we create these delta lap times with, and we found a bug in that tool that meant that it gave us the wrong number.

"The number that we were calculating was around 15 seconds, and in reality the number was slightly short of 13 seconds, so that was what created our delta.

"That is why we thought we were safe. We thought we had a bit of margin and then you saw the result.

"We dropped out, we were in second place and it is very difficult to overtake and we couldn't get through."

Shovlin said the team was treating the situation with the same seriousness as a reliability failure and would ensure that in the future it gave itself more margin with gaps to rivals.

"It is really about understanding everything that went wrong, gathering all the data, and invariably it is never just one thing," he said.

"So there are elements that we can do better with calculating that, but we have also looked at it for future.

"We are going to make sure we have more margin because we want to be able to cover for Vettel doing an amazingly good inlap to the pits, or having an incredibly fast stop.

"So with any of these things, we look at what went wrong, work out how to solve it and then put the processes in place to make sure we don't have a repeat."

Added VSC complication is caused by drivers being allowed to accelerate from the safety car line before the pits until they hit the pitlane speed limit.

Shovlin added: "It is never quite an exact science because you don't know how fast a car is going to be able to come through that pit entry."