Source- http://www.itv.com/f1Mark Hughes on McLaren's problemsLast week’s Barcelona test, and the subsequent comments from the team’s high command, confirmed that McLaren is in a surprising state of disarray on the eve of the new season.
Far from being the immaculate conception that many hailed it as at its launch in January, the MP4-24 appears to be suffering from a serious case of ‘new car blues’ – lacking downforce and leaving its frustrated drivers mired near the bottom of the timesheets.
ITV.com/f1 columnist Mark Hughes analyses what has gone wrong for the Woking team, and suggests the problem – once pinpointed – may prove straightforward to rectify. In the meantime, McLaren faces a potentially humiliating start to its 2009 campaign…
McLaren-Mercedes’ own assessment was pretty plain: car not quick enough, not enough downforce, according to Martin Whitmarsh and Norbert Haug respectively.
Given that the MP4-24 was testing at Barcelona last week covered in fluorescene, a fluorescent dye to show what the airflow was actually doing, they could hardly claim anything else.
They are officially in trouble.
The lack of downforce is manifest at the rear but the problem may not originate there – hence the effort to trace exactly what the airflow is doing and where it is differing from what the simulations show.
It’s much more likely to be a question of identifying the source of the problem than an inherent flaw in the car’s basic design and as such it is probably a problem that can be switched off relatively easily – but only once it’s been identified.
Airflow is notoriously prone to separation, whereby the flow breaks off into separate paths over a critical component and thereby does not produce the expected downforce on that component.
Computational fluid dynamics (CFD) is capable of predicting this, but not with 100% reliability.
If the problem area is sufficiently intricate, there may not be enough computing power to model it accurately.
Almost certainly, there is a small part of the car’s surface – maybe around the sidepods, the guide vanes or the diffuser – that is creating a detachment in the airflow which in turn is compromising the flow over critical downforce-producing components downstream.
Starved of flow, these components are effectively switched off even if though there may be nothing wrong with their design in isolation.
As part of its investigation McLaren was looking into whether the rear wing itself was a problem or whether the problem was just manifesting itself there – hence the switching back and forth from the 2009 wing to the known quantity of the ’08 wing.
The car still being slow with the ’08 wing – a component known to work – will have confirmed that the likely problem was upstream of the wing itself.
Nailing where that critical separation is taking place is how the McLaren’s problems will be resolved.
The quality of design simulation tools today means it’s much less likely to be an inherent flaw in the car’s concept.
Given how radically different the 2009 aero regs are, it’s perhaps not surprising in hindsight that at least one team has been caught out by the uncharted territory.
A new floor with a much more open section around the rear wheels was introduced on the car the previous week, again pointing to the team trying to generate more rear downforce – in this case by inducing a low-pressure area ahead of the rear wheels which should cause the diffuser to pull it through with greater force, increasing the speed of flow through the diffuser.
The team is continuing to test further solutions in Jerez this week in a last-ditch attempt to nail the problem before flying out to Melbourne.
On Barcelona form the McLaren appeared to be around two seconds off the pace – which would give Lewis Hamilton and Heikki Kovalainen a major problem in just graduating into Q2 in Australia.
The Force Indias may be around the same pace and the unpreparedness of the Toro Rossos because of the late completion of their cars may also limit them.
Those two aside, every other team looked comfortably faster than McLaren last week.
Unless some breakthrough is made in Jerez, they look set for a torrid time in the opening flyaway races.
Expect to see them running extensively in the Friday sessions, which, once the season has begun, is the only testing available to them.
The instant stunning pace of the Brawn BGP 001 has merely served to underline McLaren’s difficulty and the limit on testing may serve to delay a solution.
But it would be staggering if the car’s problem wasn’t identified and cured before the season was very old.
McLaren is just too good, too well resourced, to have come up with a car that really is as bad as it has looked in testing so far.
- By darwin dali