As it hits the track, Force India technical director Andrew Green talks about the thinking behind his team's new car.

Last winter there was a major change of philosophy and it paid off with a stronger second half of the season. What's has been the plan with the VJM05?
The approach is to use that foundation and carry on building on it. We have a lot more confidence in the aerodynamics we put on the car now, compared to previous years. I think that showed from the time we changed the car in Barcelona and for the rest of the season. We were putting updates on at almost every race and the performance was improving. We're happy with the strategy we've got and we're pushing the boundaries even further. So we're going to use what we learned last year as the foundation. There's been a bit of clawing back to do with the exhaust regulations and that's been the main focus of attention over the winter.

How would you sum up the new car?
I would say that the car looks a lot more refined than previous cars produced here. It does look a lot racier and a lot more purposeful. You can start to see the aerodynamic concepts coming through now. It looks quite a bit different to the previous years, which is good. And so far the performance in the tunnel has been extremely encouraging. It's just that unknown of where everyone else is - and we won't know that until Melbourne.

What impact have rule changes had?
The nose height regulation has led to the biggest visual change in the car, and then there's the exhaust regulation. The rest of it is very subtle.

Some teams spent more time than others pursuing the blown diffuser route. Will that make it easier for you to take a step back from it?
Our time was limited, as far as the blowing of the diffuser was concerned. We couldn't get it to work at the end of 2010 and that's when we had a big rethink last winter. So we only had a limited time to tune it and I know we never extracted the full potential. For the teams who were working on it a lot longer than us, it could be an even bigger hit.

What can you tell us about the latest McLaren gearbox?
It's smaller and lighter. It's a really neat and tidy package again, as we would expect from McLaren.

The Mercedes KERS was new to the team last year. Are you happy with how it worked out?
It was as close to a seamless integration as you could want. It's a fantastic system, and we're very happy with it. There are little detail changes, but essentially it's the same package.