NEW FOR 2018

The halo cockpit-protection device is just one of many new elements appearing in F1 this season

Few Formula 1 technical changes in recent years have been as divisive as the introduction for 2018 of the halo head protection device.

It has been variously branded as “hideous” and as something that will herald the death of spectator interest in F1. Others, not least FIA President Jean Todt, are adamant in their conviction that it will help secure motorsport’s future in an ever more safety-aware and litigious society.

Regardless the halo – or a refined future iteration of it – is here to stay and more optimistic readers will surely become used to it, as they have in the past to skinny cars with grooved tyres (1998); high noses and

‘anvil’ engine covers (2010); stepped noses (2012)… even the ghastly ‘anteater’ nose of 2014.

(No, scratch that, we never got used to the ‘probe’.)

Much more excitingly, F1 2018 is going to be fast. Last year fatter tyres, wider track and better aero combined to increase cornering speeds by up to 20mph. This year,

Pirelli’s aggressive new ‘hypersoft’ could shed a further second from lap times compared to last year’s ultrasoft compound.

There’s much else to get excited about; the return of the French and German GPS; Alfa’s return with Sauber; fan festivals; new race drivers and the still-hard-to-believe comeback of Robert Kubica, as Williams reserve.

Much, then, to get the racing juices flowing – but first, some technical nitty-gritty from our own Pat Symonds.

HEAD START

The halo, or to use its official name, the Additional Frontal Protection (AFP), has had a reasonably long gestation period, with several different solutions having been evaluated.

The need for additional driver head protection in open-cockpit cars has been the subject of debate for many years. But perhaps Henry Surtees’ fatal Formula 2 accident at Brands Hatch in June 2009 and the significant injury suffered by Felipe Massa in Hungary a month later, when he was struck on the head by an errant spring from the car he was following, accelerated the quest for a solution.

In November 2010, after a further incident between Michael Schumacher and Vitantonio Liuzzi on the opening lap of the Abu Dhabi GP the previous month, FIA race director Charlie Whiting told Formula 1’s technical working group that he wanted a solution found. In the Abu Dhabi accident Schumacher had spun and was facing the wrong way when Liuzzi hit his

stationary car. Liuzzi’s Force India effectively climbed up the monocoque of the Mercedes coming to rest very close to Schumacher’s head. It showed that increased frontal protection was required to mitigate the effect of a number of different scenarios.

Initial research by teams, together with the FIA Foundation, focused on providing a device that could deflect a wheel and tyre assembly away from the driver if it were to be projected toward his head. While the introduction of wheel tethers has significantly reduced the likelihood of this happening, it provides a standard with which to assess design concepts which are viable in a wider variety of scenarios.

BACK TO THE DRAWING BOARD

So it was that a tubular structure was chosen – although when this became public knowledge, the reaction from fans was intense enough to provoke a return to the drawing board and the development of a small transparent device which came to be referred to as the shield.

This was a smaller and less structurally comprehensive device, incapable of withstanding the forces associated with deflecting an errant wheel. It was designed, instead, to deflect lightweight objects such as that which had caused injury to Massa. But when Sebastian Vettel declared he had inadequate vision through a test device, it was quietly put away, and the halo was thus declared the only viable solution to the problem.

At this point, in early 2016, there was still hope of a 2017 introduction but this timescale proved too optimistic and after further development Halo 3, the current model, was cleared for 2018 introduction.

It has been rigorously tested and risk-assessed by the FIA. Every scenario was investigated, from the obvious – an object hitting the AFP

– to the less likely such as might have occurred in the Schumacher-liuzzi contact. In this type of accident, could the sharp part of the forward floor of Liuzzi’s impacting car be snagged on the hypothetical halo of Schumacher’s car, breaking off and acting as a blade, which might then impale the driver?

HEAVY LOAD

Teams now started to undertake the practicalities of installation – no trivial task. Their initial aerodynamic studies indicated the halo would definitely have a detrimental effect on engine inlet airflow and any high-mounted ducts for cooling were also suffering. An allowance of a light composite 20mm fairing on the halo helped to divert the flow and minimise this effect, as well as controlling the halo wake, which is projected rearward toward the rear wing.

Much more significantly, designers have had to consider how to strengthen their 2018 monocoques to cope with the tests involved in signing off the halo installation. These consist of two loads which have to be applied to the structure once fitted to the chassis. Here, the AFP will also act as the secondary roll structure.

Test loads apply a resultant force of 125kn to the device – equivalent to resting the anchor of the Queen Elizabeth II on top of the halo.

WORTH THE WEIGHT?

This is a stressful time for teams: even a small error in manufacturing can lead to the catastrophic loss of a chassis and a significant set back in the development programme, which might take months to recover from.

Halo testing has been carried out under FIA supervision, with loads applied via a powerful hydraulic ram onto a fully homologated Halo 3 structure – each one costing £12,500. To pass, it must be shown that the structure can withstand 150kn and the ability to resist such loads comes at a cost. While the tubular part of the halo weighs 5kg, the teams estimate a further 5-7kg of carbon fibre and inserts need to be added to the chassis.

For 2017, the minimum weight limit was increased from 702kg to 728kg, to account for the increased width, tyre sizes and fuel capacity, as well as the halo that was supposed to be introduced.

Even so several teams still struggled to hit that target and this year we’ll likely see more of the same, so drivers will once more be forced to shed body weight.

TRANSPARENT SOLUTION

It’s unlikely the halo we see in 2018 will be the ultimate AFP solution, although the various transparent devices trialled already bring their own problems – even if they do look cool and futuristic. And while the engineering and operational aspects of screens could and would be overcome, screens do have one major negative: they tend to hide the driver. No-one will pretend the current system is aesthetically pleasing and the cost of developing alternatives cannot be ignored. But that shouldn’t preclude the possibility of the design being better integrated in future.

Indeed, F1 will undoubtedly see some major visual changes to the cars in 2021 when the first fruits of the work being done by the FIA with input from FOM bear fruit. It should be feasible to achieve a design in which the AFP appears to be an integrated part of the chassis, rather than something that happened to land on an F1 car. The concepts of a frontal roll-hoop structure and a clear cockpit canopy were both extensively evaluated before halo was settled upon as the best AFP solution.

Indeed, early tests in 2011 were on an F16 aircraft canopy. These FIA tests fired a wheel assembly directly at the canopy. It had been calculated that the energy of impact in Henry Surtees’ accident was around 40kj – equivalent to a 20kg wheel assembly impacting at about 140mph. The F16 canopy was designed to withstand a 73kj bird strike. To put this in context a helmet visor can only withstand an impact involving energy of about 500 joules, around 1.25 per cent of the requirement of the halo.

From these tests it was obvious that stopping an errant wheel was impractical: the energy involved implied a force of nearly 40 tonnes would be applied to the structure. Deflecting the wheel over the driver’s head, however, reduced the load to around six tonnes. This is still a significant force, equivalent to a fully-grown elephant sitting on the structure, but one designers felt they could manage.

It was further decided at this time that a fully closed canopy was not desirable either from the recognition of F1 as an open-cockpit formula or from the standpoint of safely extracting a driver after an accident.

While this work was going on, Red Bull continued to develop an openscreen concept. This consisted of a 30mm thick laminated canopy which was subjected to intensive FIA testing. Mercedes and Ferrari meanwhile championed a tubular structure.

Unfortunately, with two different concepts and considerable testing and development required, the project was in danger of turning into a never-ending science project and some decisions had to be made. Around this time the canopy suffered a catastrophic test failure which, although perfectly capable of resolution, polarised opinion with deadlines looming.