• INSIGHT: Australian Grand Prix Debrief: Your Questions Answered

After a topsy-turvy weekend in Melbourne, we asked you to send in any questions you had about the race. This week, Trackside Engineering Director Andrew Shovlin steps up to answer

'It's never quite an exact science'

Chandeep Singh got in touch with us on Twitter to ask:

How is the delta calculated between the two drivers and how does it change in the pit lane? Isn't the pit lane part of track?

Andrew Shovlin: "The delta time is the difference between a car staying out on track and a car coming into the pit lane.

"During the VSC (Virtual Safety Car), all of the cars on track have to slow down to a much reduced pace to make sure it is safe for the marshals to work. We get that profile from the FIA. They tell us how fast the cars have to drive and the drivers try to stick within a few tenths of a second of that time.

"We know how fast the car can come into the pit lane because there is a 60km/h limit. The cars coming into the pits are also following that delta time until they get to the Safety Car line. Then, there is a period where they are free to accelerate and decelerate down to the pit lane limit.

"During the weekend we are collecting a lot of that data. It's never quite an exact science because you don't know how fast a car is going to be able to come through the pit entry and you don't know how closely they will stick to the delta.

"But, it's essentially the difference between the time it takes to come through the pit lane and the time it takes to stay out on track on that reduced speed limit."

'We thought we were safe'

LJ Wilson asked us the following question on Facebook:

What will change with the software to prevent what happened occurring in other races? Wishing the team all the best for the season!

AS: "We identified that there was an issue with the software, which was telling us that Lewis was safe at that point and that Vettel would drop out behind us. Obviously, Vettel exited the pits in front.

"The issue isn't actually with the race strategy software we use but an offline tool we create these delta time laps with. We found a bug in that tool, which meant it gave us the wrong number.

"The number we were calculating was around 15 seconds and in reality the number was slightly short of 13 seconds. That was why we thought we were safe and had a bit of margin.

"How we deal with these sort of problems in the software is the same if we had a reliability issue. It is really about understanding everything that went wrong and gathering all the data.

"Invariably it is never just one thing. There are elements that we can do better. With any of these things, we look at everything that went wrong, work out how to solve it and put the processes in place to make sure we don't have a repeat."

'Trying to lose as little time'

Alan McClary commented with an interesting question on Facebook:

Can you please confirm that the pit lane, where Sebastian accelerated, is NOT a part of the track? I thought that track rules applied until the pit lane limit line?

AS: "Well, absolutely, he is allowed (to accelerate at pit entry). When you are on track following the delta time, you only need to follow it until you get to the Safety Car line.

"As soon as they cross that line as they come into the pits, they can go as fast as they like around the bend into the pit lane and then slow down to the 60km/h limiter.

"So, braking hard down to that line, trying to lose as little time as possible and heading through the pit lane on the limiter."

'We were just around the limit'

RNB44 replied to our post on Twitter with this question:

Is the engine OK on Lewis' car after pushing after Vettel in the latter stages of the race? If so, how can you test it? And would it be used in future on non-power tracks like Monaco / Singapore as a precaution?

AS: "You may have heard us on the radio telling Lewis his engine was getting hot. That is just the fact that when the cars get so close, you don't get clean air going into the radiators to keep it cool. It did get quite close to limit temperate but we are monitoring these limits very closely.

"You can run up to the limits, you just have to be careful you don't run over them. In Lewis' case we were OK and just up around the limit. You heard Lewis say on the radio he couldn't get past and he was going to save the engine.

"At that point, he just backed off, was cooling the car and could turn down the power of the engine so it was not having to work so hard. But, we are pretty confident the engine will be in good shape.

"We are limited in what tests we can do because we can't actually run the engine, we are not allowed to until we get to Bahrain.

"In terms of where it will be used next, at the moment that's Lewis' only engine in the engine pool, so he is going to be running that engine in Bahrain and China. We will be monitoring them as we always do to ensure everything continues to be OK."

'The car was quick enough to win'

Andrew Pilborough got in touch on Twitter to ask:

Could Lewis have pushed harder, if instructed, to make sure the gap for VSC was covered, same as the undercut? I don't see how the gap was big enough for the pit limited straight to gain such an advantage?

AS: "The simple answer is we could've pushed the car harder. At this point of the race, we were still following a fuel profile, which meant we were having to do some saving of fuel. Melbourne is a very difficult race to do on that 105kg limit.

"Also, we were being cautious with the tyres. Because the team thought we were safe anyway and thought Sebastian would drop behind us, we weren't telling Lewis to push any harder. That is one of the big frustrations that we have coming away from Melbourne.

"The car was clearly quick enough to win the race and if we had managed the race differently, we could've won it. But at this point, we were lulled into this false sense of security and we didn't have Lewis driving as fast as he could.

"So, that's one of those areas where in future we need to make sure we have got more margin and that all of these tools are giving us the right instructions, so we can put the car where we need to on track."

'We couldn't have done it'

Blake Lyons also commented with a question on Twitter:

Could Lewis have driven through the pit lane and not stopped (a bit like a drive through penalty) to keep the lead of the race?

AS: "I'm not sure if you mean when we had the VSC, because Lewis was already behind and if he'd come through the pits we would've still been behind.

"The other problem is there is a regulation that says when there is a VSC, you are only allowed to drive through the pits to change tyres.

"So, the short answer is no, we couldn't have done it. It certainly wouldn't have helped Lewis at all because coming through the pits was still quite a bit slower than staying out on track."

'P8 was the most probable result'

Another interesting question on Twitter was this one from Berend Clemenkowff:

‏After Bottas' crash in qualifying, what was his projected end result for the #AusGP? Was P8 in line with pre-race expectations?

AS: "You saw Valtteri had a crash in Q3, which would've put him 10th on the grid because he hadn't set a lap time. But we also damaged the gearbox in that accident, which was another five-place penalty. So, he was starting the race in 15th.

"Overnight on Saturday, we were running hundreds of thousands of simulations, each one is like a mini race. We look at what happens, whether they can overtake, lots of different scenarios. So, when we talk about projected finishing position, it's really a probability.

"P8 was actually the most probable finishing position for Valtteri. His very best result would've been around P6 and equally there were other scenarios depending on when all the other cars stopped that would've put him just outside the points.

"Realistically, when you see how hard it was to overtake in Melbourne, P8 was about the best he was going to do."