A feature of every F1 car since 1996, the cockpit headrest padding has evolved to become a critical safety feature. Introduced as part of the response to the incidents of 1994 and in particular the Wendlinger Monaco accident, the regulations are now very specific in regards to the shape and material of the padding. Although outwards these are simple pads, their design is tightly governed by the regulation the final detail is balanced between the drivers and the aerodynamicists.
Although some form of headrest has been a feature of the formula many years, the vestigial pads behind the drivers heads did little for the drivers protection in any form of accident. Often teams would fit a small section of padding to save the drivers from the cars acceleration. Even before 1994 the head rules were imposed in 93 and 94 to enforce a headrest behind the drivers of head firstly with a minimum area, then with a minimum thickness. But Wendlinger’s side on crash out of the tunnel at Monaco, saw the low cockpit sides and lack of padding fail to save the driver from head and neck injuries from the lateral impact. In the wake of the crash Sauber unilaterally elected to fit higher and padded cockpit sides, then these protective structures were written into the rules in 1996.
As a result of crash tests carried out to investigate the mechanic of crashes in F1 cars, the FIA recognised that in a side impact the drivers could be shaken from side to side, resulting in injuries, to the brain, head and neck. Having padding would reduce the loads the driver is subjected to preventing serious injury. Meanwhile the further extension of the rear headrest will reduce the accelerations seen by the drives skull in rear impacts and from whiplash in frontal impacts.
Initially the rules used a line in between the front and rear roll hoops to define the position of the padding, with 75mm wide pads being required either side of the drivers head. The regulations evolved to make these designs longer (reaching the steering wheel) and the front and side pads made from one piece.
In the first years of these rules different teams took different interpretations of the regulations, Some teams were very literal in the adoption of the side padding (Ferrari) and other teams reworked their roll hoops to effectively reduce the height and angle of the padding (Jordan). As the designers played with the definition of the roll hoop, teams like Jordan moved the reference point of the roll hoop backwards, making the angle of the mandatory padding much flatter, creating less aero blockage in front of the rear wing.
With the teams ending up with very different heights and angles of padding , the FIA responded with a new set of rules outlining the dimensions of the cockpit opening and the padding. These rules still stand today, albeit the padding has been widened to 100mm thick from the original 75mm.
Outlined in Drawing2 of the technical regulations, these new rules define the padding, although teams can chamfer and fair-in the padding to suit their own aerodynamic philosophy. So although some team’s cockpit padding may look very different, they have the same underlying dimensions.
What we have now ended up with is a removable padded collar that fits into the cockpit surround, thereby being retained by two pip pins at the front. Removing these pins allows the padding to be removed. Some drivers prefer to remove this before exiting the cockpit. Although it is perfectly possible to exit without the padding being removed.
As demanded within the rules the padding must be Confor foam. This foam is relatively soft when touched, but when subject to a severe blow the foam hardens to absorb the load and is then slow to bounce back. This characteristic protects the driver from both the initial blow and any whiplash response.
As this foam is heat sensitive there are two specifications required for different ambient temperatures, the FIA will inform the teams which specification must be used for a specific event. A Blue foam (Confor CF45) is used for ambient temperatures over 30c and pink foam (Confor CF42) for temperatures below that.
To aid aerodynamics teams cover the foam in a very thin layer of carbon fibre. Unlike other sections of carbon bodywork this covering is flexible and almost rubber-like. It will not add any undue resistance to the helmet hitting the foam in the event of an impact. It’s when the padding is removed from the cockpit, that you can see the coloured padding within the aerodynamic cover.
As with any part on an F1 cars teams want to exploit any possible aerodynamic advantage, with these “U” shaped pads, teams are able cover quite a large section of the open cockpit, thereby reducing drag. Under the current rules teams initially kept the pads a narrow as possible around the steering wheel area, to provide the drivers with clearance for steering and cockpit exit/entry. Now teams bring the padding in as much as possible with the smallest possible clearance around the driver’s hands near the steering wheel.
For example Red Bull have a unique way of fairing-in the angled section of padding. Rather than exposed the ramped leading edge of the padding to the airflow, the cockpit side is built up and a rounded leading edge is presented to the airflow.
A Honda trick that has been continued by Mercedes is to have a bead running around the inner face of the padding.
So despite the stability in the rules dictating these headrests, the design will alter year by year and will even differ in between drivers as the demands of aerodynamics and driver comfort are balanced. The presence was vindicated last year when Sergio Perez also in a Sauber, had a near identical accident to Wendlingers 94 crash. The headrest padding as well as circuit improvements, reducing his injuries to concussion rather than a coma.
The Sahara Force India headrest shown in this article is available along with other Formula1 and Sahara Force India parts from Memento Exclusives