Technical Q&A
Mark Smith, design director
Design director Mark re-joined Force India in November 2007 to lead
design and production of the team's current challenger, the VJM02. Mark
takes responsibility for the day to day running of the Design Office and
Research and Development.
Aside from the aero regulations, what are the principal differences from
the 2008 season for Force India?
From Force India's perspective the main change we have had from 2008 is
the new engine from Mercedes-Benz and the gearbox from McLaren. When we
confirmed the partnership on 10 November 2008 we had to adapt our plans
fairly significantly. It's not just a case of getting the new parts and
installing them; when we changed the gearbox, it had slightly different
suspension mountings and when we changed the rear suspension there was a
necessary change on the front. Other areas subject to change were the
fuel cell, and the cooling system. All have been challenges in their own
right, but not day and night differences as you've seen on the aero side.
As you say, the deal was announced on 10 November. Has the timeframe been
the biggest challenge?
Adapting to a new engine and gearbox is not actually fundamentally
difficult, the biggest factor has been the timeframe we have worked with.
We had got a fair way down the line with our 2009 plans at that point and
then had to adapt them to the new suppliers. Normally you would have
started in August, so we have had to compress everything into five
months. Everyone has really worked hard to make it work and we've got a
potentially better package, so the change has been a positive rather than
a negative.
What exactly does the McLaren-Mercedes partnership comprise?
The package announced comprises the supply of engines, gearboxes,
hydraulics systems and KERS to Force India.
Will Force India run KERS this season?
Our car is fully KERS compliant but whether we run the system will be
decided jointly by Force India, McLaren and Mercedes.
And this year sees the return of slick tyres. Has this had a major impact
on design?
Running a new tyre compound does have some impact, especially as we have
had limited running on slicks. There are a number of solutions you can
apply on camber and suspension, or factor some items into the geometry.
At this stage however we are dependent on the previous running or data we
have received from Bridgestone, but the impacts at this time are quite
subtle.
Have the new partnerships had a real impact on the workforce? Have you
restructured the team in anyway?
We haven't seen the whole benefit just yet as we have been working flat
out on the car but so far everything has been positive. The relationship
has been very good and we have gelled very well given the limited amount
of time we have worked together. The big talking point has been how we
approach development, how we track test items, how we introduce
significant updates. The process works well.
Obviously with the car launching so late, testing is going to be even
more crucial than ever. What will the plan be?
We will have eight days of testing, plus two shakedowns. The first
shakedown, which took place at Silverstone on 25 February, allowed us to
determine and fix any major issues, check the systems and so on, and then
the Jerez test will be to identify the aero load on the car and get some
feedback on handling. Following this test, we'll see where we are, assess
any outstanding problems and then try to fix a set up for Melbourne. The
next test will be in Barcelona from 9 - 12 March.
Will the late debut be a problem?
Ideally you would have more testing, but it isn't a major issue. One of
the biggest disadvantages will be knowing what the life of the new parts
is. Normally in pre-season testing we would put more life on each part
than it would be subject to under race conditions, but with only eight
days we won't be able to do this. It will just put a greater onus on rig
testing and Grands Prix Fridays.
Now that testing is banned in-season, is this going to hamper development
for teams such as Force India that have debuted late?
With no mid-season testing it does make life more difficult, but you
should never be in a situation where you put a part onto a car and have a
doubt about it. Really you would use a test to check the reliability and
the life, rather than whether it works. It does mean we will have to be
smarter with regards to reliability and also that Fridays at a Grand Prix
will be more valuable than ever. I think we will see real work conducted,
so car set up, development and mileage rather than simple tyre
comparisons. It will certainly make the weekends more exciting.
James Key, technical director
James Key is a long-standing member of the team, first joining Jordan
Grand Prix in 1998. Over his ten year period with the Silverstone outfit
James has worked his way through the ranks, becoming technical director
in 2005. He now oversees aerodynamics, vehicle science and R&D for the
team.
The shape of the VJM02 is radically different from that of its
predecessor. Can you talk us through the new aero rules and Force India's
interpretation of them?
The aerodynamic regulations are completely different this year, to the
point where we are almost starting from a blank sheet of paper.
If we talk through the car from the nose, the front wing looks very
different. The wing must be 1800mm wide by regulation so it stretches to
the widest point on the front tyres, making it look very flat and,
obviously, extremely wide in comparison to the 2008 wing. With an
FIA-prescribed central section, and two working sections that are towards
the outside of the wing, it also works in a very different way from last
year. In 2008 this wing was narrower and the whole section was working
very hard and pushing the air flow inside the tyres and under the car.
Now, the air hits the front wing and its up-wash is directly affected by
the tyre so it must flow in several different directions , which creates
a much more complicated problem, particularly as the rest of the bodywork
is also subject to very strict regulations.
The bodywork is now much more like a 'jelly mould', that is there are no
elements hanging off the bodywork, so no bargeboards, chimneys, louvre
panels or any 'add on' devices that manipulate the flow of air over the
car. All the bodywork must comply to a set of 75mm radii so the VJM02 has
a much more curved, clean profile compared to 2008. Of course the lack of
these outlet devices and the changes on the rear has had a fundamental
impact on the cooling of the car. Now there are only two cooling exits,
and the air has to exit via the rear of the bodywork just ahead of the
rear wheel centreline.
Moving to the rear of the car, the diffuser is lower, wider and further
back on the car. The second more obvious difference from 2008 is that the
rear wing is a lot higher and narrower. The maximum width of the wing is
25% smaller with only two wing elements. It's now a lot more aligned with
the rear diffuser so more difficult to get them to interact compared to
2008.
In another new regulation, the front wing is also moveable.
Yes, the front wing is the only legal driver-adjustable aero device on
the car. It is activated by a button on the steering wheel. It can be
moved up or down by three degrees and is there primarily to help with
overtaking. In previous seasons we have had situations where cars could
follow one another but couldn't overtake as the front end lost downforce
and grip when the cars got too close. Now, the driver can adjust the wing
twice per lap so if he is following a car he can get close enough to pass
on the exit of the corner.
Another benefit is that if the car develops a handling issue, such as
tyre degradation for instance, the driver can hit the button and try to
address the problem.
Has any of the 2008 testing helped?
In the last part of 2008 we set the car to 2009 drag and downforce levels
to get an idea of how the car would behave with the new regulations, but
very often we had a cold track and it hasn't been very representative! We
know we have compromised on testing with the late debut of the car, but
we have a very defined winter testing programme from now on and in
general the positives on the McLaren/Mercedes deal have far outweighed
the negatives.
Has the relationship with McLaren and Mercedes had an impact on the aero
design of the car?
To a certain extent, yes, as we have had to adapt the bodywork to fit a
new, slightly different shaped engine, gearbox and KERS. We haven't had
to start from scratch but we have had to repackage and redefine certain
areas, such as the side pods, cooling and the rear of the car. We spent a
long time trying to get the bodywork right and the guys in the wind
tunnel design office have done an excellent job in interpreting the
regulations. It is still very early days and I think we will still find
new directions as development progresses.
-credit: force india
