Technical talk with Force India's Andrew Green
The Force India Formula One Team's VJM04 is the first car created by the team under its new technical director Andrew Green, who exactly 20 years ago was one of the men behind the original Jordan 191.
Green and rest of the Silverstone-based team faced major challenges created by the changes in the 2011 FIA Technical Regulations, with a cut in downforce and the movable rear wing chief among them. In addition Pirelli has become the new tyre supplier, and the teams have agreed to allow the use of KERS again. The result is a car that is very different from its predecessor.
"Everything is different, but visually a lot of it is subtle," says Green, who re-joined the team in July 2010. "The most obvious visual change is that we've gone away from a conventional roll-hoop to a blade. This gives us a small packaging improvement compared to a more conventional style. The engine cover is different, in-line with the abolition of the F-duct system. But there are a lot of differences under the skin that people won't necessarily notice."
The ban on double diffusers and other changes in the rules created a drastic cut in downforce at the rear of the car. Getting it back has been one of the major challenges of the winter.
"We've recovered a lot of the aerodynamic performance, we believe. We still have a little bit to go, but we are still in the process of the realignment after the end of last season, because it does take a long time to move aerodynamically from one position to another. The movable wing is a whole new game, and we'll be trying to exploit its performance to the max.
"We've also put in a lot of work trying to maximise the potential performance of the new Pirelli tyre compounds. To this end we've recruited a new senior tyre engineer, Jun Matsusaki, to guide us through the development process. The test we recently conducted in Valencia was a good learning exercise.
"Exhaust management will also be a big area of development this year. There will be an upgrade for the first race, so there are some changes that will come into effect at the Bahrain test. Further down the line there are some big updates for the front of the car coming in for the first European race."
Significantly the team has done far more than simply address the new rules. It has also gone back to basics by taking a close look at the fundamentals of last year's package, and attempted to address key areas of concern.
"Towards the end of last season there was a drop-off in our relative performance,' says Green. 'In theory we were adding performance to the car, but it wasn't getting translated to the track. We decided to have a very close look at what was happening on the car, and what could be causing this. The bottom line is we didn't extract the most from the blown diffuser, thus over the winter we've taken a reasonable philosophy chance on the aerodynamics of the car in order to try and prevent the sort of drop-off in performance that we saw at the end of last year."
In addition the team has focussed on improving its performance in high downforce spec.
"Looking back over the years the cars we have produced here have always struggled at the high downforce tracks - they always been 'slippery' cars. We've identified a problem, and now we have to fix it, and it means that potentially there's another strategic aero change coming as well."
Underlining the team's renewed focus on aerodynamic development, there will extra emphasis on gathering data on the Fridays of race weekends.
"We are going to be using the real car at the track as a validation tool for the aerodynamics, which is something that we haven't done effectively before. There's a lot more focus on what's actually happening on the car aerodynamically. To measure it at the fidelity that we need to measure it at is a huge task.
"We understand how important it is, and we're in that game now as well. That will start to feed back into the aerodynamic development of the car. When we get positive results it backs up our development tools, and when we don't, we'll investigate why. Fridays will be a lot more about understanding the car we have as well as understanding the track at the time and the tyres you're running."
The change requires more accurate sensors and different procedures for gathering data, better analysis tools, and dedicated people at the trackside focussing on the aerodynamic performance.
Force India is not entirely new to KERS. The 2009 car was designed to utilise the Mercedes system and the team ran it in testing, although it was never raced.
"The Mercedes KERS system looks very strong, and we're really happy with it. We've done a lot of running in the simulator, so the drivers are well up to speed with how to use it. We're well developed with what we have to do for harvesting and deployment. It's smaller and lighter than in 2009, and packaging required very few vehicle compromises."
Summing up, Green says the intention is to build momentum over the course of the year as developments come on stream, and the aero work pays dividends.
"There are some big developments in the pipeline, probably bigger than this team has seen for quite a while. I think we're looking for a much stronger finish to the season, and we do recognise the fact that there's an Indian GP on the calendar, and we are an Indian team. The plan is to be putting stronger performance on the car through the year that will lift us up the ranks."Source Force India