This F1 Forensics is brought to thejudge13 readers in partnership with SomersF1, Like most of us, Matthew Somerfield has a day job and his is being the manager of a car & van rental company in the Isle of Wight.
His passion is to try and bring us non-techies closer to F1 by bridging the gap between the full blown engineering publications and the simplicity of much that is provided by TV.
Some of you were asking for this kind of forensic look at the FRIC system a couple of days ago – so by popular demand, here it is. Over to Somers…
McLaren 2013 – Where did the pace go?
McLaren’s stuttering start to their 2013 campaign is likely to take a turn for the better in the second half of the season. But why have the team struggled so badly so far and is it now too late to do anything about it?
Well lets first understand why McLaren find themselves in the situation…
Having finished their 2012 campaign in strong form fans of the Woking based outfit had no reason to believe their team wouldn’t be challenging for victories early in the season.
Having already assessed and acknowledged the plausibility of using Pull Rod Front Suspension late in 2012, no-one was shocked to see it on the MP4-28 at launch. With Ferrari having had teething issues early into their 2012 campaign with their own front Pull Rod layout it could be argued that was the risk worth the reward? McLaren believed so as they admitted that extracting larger gains from the ethos employed during the design of the MP4-27 would be difficult.
The MP4-27 at stages throughout 2012 was the quickest car but also remained kind on it’s tyres however it often struggled to bring the front tyres up to temperature, a trait which was exacerbated by Jenson’s smoother driving style. This was more of an issue as the season progressed and the other teams closed the gap to McLaren’s early pace resulting in qualifying becoming more essential.
McLaren’s application of Pull Rod Suspension at the front of the car was designed to aid in the phasing in of the front tyres that it’s predecessor lacked as the higher geometry of the Suspension forces more shear load through the tyre, in turn heating it up. This is all well and good until we realise that Pirelli’s change in tyre construction for the start of 2013 meant that the tyres operated differently, the Sidewall was more forgiving and the tyre naturally came up to temperature more easily.
Now lets also think about the aerodynamic impact of the tyres, with this more forgiving Sidewall both the tyre itself and the relative position of the suspension components change more dynamically. McLaren have for a number of years now run their cars very stiff, this enables the designers to work more closely with the aerodynamics of the car but makes the car less mechanically compliant.
Part of their problem therefore is that with the suspension being virtually rigid the damping of the cars movements is further expressed through the soft sidewall of the tyres. This of course has an impact on both the mechanical and aerodynamic principles of the car causing already peak laden airflow area’s to be pushed outside their operating windows.
The use of pull rod suspension was not the only big revision envisaged for the MP4-28 with the team who almost stood alone in their adoption of the lower nose during 2012 yielding to a higher one this season. The car and the thought processes behind these changes are of course to increase the cars potential whether that be initially and/or throughout the course of a season.
McLaren were vocal in their opinion that the MP4-27’s potential had been reached at the end of 2012 and so wholesale changes were required for 2013 to stay with their rivals. The DNA of the car therefore is inherently different with the chassis / bulkhead raised close to the height limit of 625mm rather than the 575mm it’s predecessor ran at. This impacts many area’s of the car but none more so than the area the team were trying to make strides with: The Sidepod’s frontal region.
McLaren started their 2012 season with the ‘Coanda’ exhaust and was swiftly copied by most of the field, realising that more potential could still be unlocked from this the team knew they must exploit the lower frontal section of the Sidepod. The raising of the nose and chassis also leads to an increase in the height of the Sidepod and therefore more surface area that can be used to condition the airflow that leads to the rear of the car. The problem for McLaren however is their plans were scuppered when the scale tyres provided by Pirelli didn’t react in the same way on the car.
The tyres dynamic movements allied by the stiff suspension run by the team meant the additional airflow traveling under the car (due to the raised nose/chassis) was being disturbed by both the tyres and lack of compliance from the suspension. This led to some swift changes by the team in order to try and rectify the deficiencies but these were simply a band aid with the disturbed airflow not only destabilizing the car at the front but having an onward effect on how downforce was generated at the rear of the car.
If I had to mention one thing that McLaren changed that pointed toward this situation the most it would be the team abandoning their 3 tier under chassis turning vanes during pre season testing and replacing them with single element vanes under the nose. The vanes are used to enforce the Y250 region (The area under the nose, 125mm either side of the centreline) and help to set up the airflow to both the Splitter and the frontal region of the Sidepod.
By not only going to a less complex design but also moving the element forward it was an admission that something wasn’t working as first predicted. Although I have mentioned this throughout my ramblings on twitter, my own blog and such like I was vindicated when McLaren returned to the more complex vanes whilst testing the newer (2012 construction) Pirelli tyres at the Young Drivers Test.
Of course this wasn’t the only change made, with the team needing to rectify the potential losses they expected to gain by the enlarged surface area of the Sidepods undercut. The re-introduction of Vortex Generators on top of the Sidepod and a re-design of the Sidepods downwash to the exhaust were needed to make the Sidepod operate over a wider speed range and maximise the downforce being generated.
Furthermore, many people (including myself, albeit perhaps not so vocally) were dismissive about McLaren’s Front Wing ethos with the team still only running a relatively basic 3 tiered flap arrangement. The deltoid shaped wings that are en vogue in F1 today of course create downforce but also serve the purpose of creating more complex flow structures to manage tyre wake.
An F1 car requires balance and so adding more front downforce requires more rear downforce, the older generation front wing was more than capable of creating the required force but doesn’t create the same level of vortices you would see from the likes of a Red Bull front wing.
Even though McLaren seemingly buckled to the pressure from the media and their fans to follow the deltoid route they haven’t fully embraced it with the Front Wing still only using 3 tiers.
Adding additional tiers to the outer portion of the wing like their rivals would require a new ethos and a rethink about how their Endplate is constructed too. The team currently allow airflow to migrate inbound from the Endplate side aiding in the Wings ability to generate downforce in Yaw whilst the others teams increase the number of tiers to do this job and allow airflow to migrate outbound of the Endplate.
McLaren’s fortunes obviously turned around in Hungary with their car certainly more suited to the Pirelli tyres taken there and which will be used for the rest of the season. Their season is almost certainly over in terms of winning either Championship but I do believe they will now have much more of an effect on who does triumph. Their closest rival (this season) Force India will now find themselves much further pushed by McLaren, whilst Sauber, another team who have struggled this season, should too find life easier from here on in (for many of the same reasons as McLaren).
If you’re a McLaren fan, armed with this news you’d be forgiven for being more optimistic but the team have already suggested that any upgrades for the rest of the season will be circuit specific or be the groundwork for their 2014 challenger. Although I don’t believe the team are anywhere near challenging for a win, through good strategy and/or tyre management they could however pick up some podium finishes.