How did you approach the STR13 project?
JK: There were several challenges but none that were by nature unfamiliar to us at Toro Rosso. The most obvious is that we have had a change of engine partner and there were also a few minor regulation changes on the aero side, a few clarifications on suspension and so on, which all had an effect on how we approached these areas. Fundamentally, it's been a case of adapting what you know to the regulations as they came out, which is pretty much the normal process from one year to the next. The most visible new element and one of the most talked about, is obviously the driver head protection with the Halo. That was a fresh challenge because there was no reference data from previous years to base anything on. We therefore started from scratch on how to integrate it into the chassis. The very tough requirements for its structural integrity and that of its mounting in the chassis were quite a challenge to ensure that we were on top of it. One of the reasons Halo looks like it does - which is one of the things that's been a bit of a topic of conversation - is that it has to be incredibly strong and to withstand the enormous loads it is intended to resist, you're not necessarily going to have this beautifully faired-in component. It's going to be something that's a bit raw. It's very much a structural item rather than a styling exercise. The Halo has been designed to a very strict set of mechanical and structural integration requirements. The load testing that you have to be able to apply to the Halo is absolutely huge so that was a big challenge.
For the rest of the car, other than engine, it was a case of taking what we knew and either completely rehashing it or refining it, depending on whether it was a strength or weakness from last year, while also applying the lessons learned from the first year of these new chassis regulations. So the 2018 car is a bit of an evolution in some areas. However, we have completely redesigned a lot of the areas at the back of the car and the way the suspension works because that was something which was not a strength in 2017, but we identified those concerns and addressed them in the 2018 car.
The aero side is, in some areas quite different to the 2017 car, in others it's an improvement of what we had. Aero is an area where there is a great deal of work in progress at the moment. It's something that was OK for us at the beginning of last year, but then we did not develop to the level we really wanted to be at by the end of the year. Some aero development is an obvious evolution of last year and some is completely new and that will be an ongoing process in 2018. There's still an awful lot to find within these chassis regulations. We'll likely have a very different-looking car come mid-season compared to where we start the year, aero development is a major focus for us at present.
Let's come to the biggest change of all - the engine.
JK: We've had several engine changes in recent years so dealing with it is something we're good at. Although the timing was later than you'd like it to be, it was not so much of an issue to try and adapt the car to it. Over the years, we've learned well how to have that flexibility within the team. The installation side of the engine to the chassis was generally OK. Certainly, we'd have made a few different decisions had we been able to do it in more normal time scales, but it hasn't been something that's fundamentally changed the cars architecture and the installation itself is very tidy. Honda has produced a very compact, very easy to work with power unit. That was a welcome discovery when we first began to get the CAD data through and started to have technical discussions with them. It also meant we could redesign our gearbox in a way that allowed some of the rear suspension internals to be better installed, so there were several benefits to the installation itself. That was a positive thing. In terms of working with Honda, it's of course a new experience. I personally worked with Honda years ago and enjoyed that period, but it's a new experience when you have a new engine partner that's not based in Europe, so you can't just pop over and visit and have a chat around a CAD screen. It has to be a much more structured form of communication. We have a much bigger time difference to deal with, which can also be something that you need to carefully account for. Another important aspect of this partnership is that it's a "works" engine deal, which is a fantastic opportunity for us and a good opportunity for Honda to work with a new and different team in the era of these power units. For us, it wasn't just a case of installing an engine and discussing all the plethora of details that go with that - the software, the electronics, even the garage layout, the operation of the engine itself, the cooling systems - it was also being able to be much closer to our engine partner and have some genuine influence over certain items. For us it's been a big challenge in that respect, to move on to a new engine supply as a "works" team and get involved to that level, but it's been a great experience so far. To sum it up, Honda have been a breath of fresh air to work with.
Pirelli has introduced an even softer tyre this year. Is that something you take into account at the design stage?
JK: Yes, because the combined effect of continued development on the aero side and on the power unit, along with more grip from softer tyres means the speeds are going to be greater. Therefore, you've got to ensure that is a part of your prediction for loading conditions for the car. You also have to consider that it might bias the way in which you need to set up the car and the way in which your suspension geometry might need to adapt a little bit to a range of tyre compounds that are, on average, softer than last year. The tyres are super critical of course and if there is a change of that magnitude, then there is a bit of work there which you need to do."
How would you sum up the year ahead?
JK: It's going to be a building period with a new partnership, but we'll mature as the season progresses and we are taking it one step at a time. I expect that as the season goes on so our package will become increasingly competitive. We have short and medium term plans in place to get where we wish to be and we are working on those in detail now – where we are in the latter part of the season will I hope be representative of where we can be, and form the basis of where we need to go next.