Managing driver comfort and heat stress
For all the focus on developing a Formula One car to improve performance, relatively little is done to improve the driver’s physical conditions when seated in the car. Most of the allowances for the driver are as a result of safety requirements, but comfort and heat stress are equally important factors.
Safety in the cockpit, aside from the fundamental function of the monocoque as a survival cell, is largely about driver restraints and fire protection. Each driver is held in place by a six-point harness system, the wide 3 in belts wrapping around sturdy mountings bolted into the monocoque. The central buckle that twists to undo the belts is completely detached when undone, and teams will often stick this to the cockpit side with Velcro when the driver is out of the cockpit to prevent losing it. Now that a head and neck support (HANS) device is mandatory, the shoulder belts feature a secondary strap that goes over the collar, thus the main shoulder straps are against the driver’s shoulders and not the HANS device itself.
The driver’s seat itself is no longer a simple A-B foam mould taken at the seat fitting. Instead, a similar seat fitting process is completed, but the foam ‘seat’ is then 3D-scanned so that a seat mould can designed in CAD, complete with mountings and accommodation for the straps to allow the seat to be lifted out complete with driver in the event of a crash. Finally the seat is moulded in carbon fibre with some limited padding and/or covering added for a tiny degree of driver comfort. Although minimum cockpit dimensions are now specified in the rules, the cockpit is surprisingly wide around the driver’s waist, although the resulting seat will often feature an open bottom and other cut-outs for clearance around the insides of the tub, to the detriment of driver comfort.
While rarely used, a critical system is the onboard extinguisher; a small carbon fibre fire bottle is custom made to fit into the recess in the monocoque under the driver’s thighs. The extinguisher will have one outlet under the dash and another in the engine bay, and it must discharge 95% of its contents in no less than 10 s and no more than 30 s.
Nowadays there is no requirement for the car to carry a medical oxygen supply on board. The sight of the drivers needing a breathing tube hooked into their helmet in case of fire disappeared in the 1980s.
A near-permanent fixture now though is the drinking tube passing into the helmet. Every car has a small drinks systems installed, usually consisting of a small flexible bladder containing a litre or so of liquid that is pumped into the driver’s tube via a windscreen washer-like pump controlled from the steering wheel.
Cooling inlets also pass into the cockpit. As the driver’s feet are just behind a hot hydraulic steering rack, and his seat is surrounded by electronic boxes, the cockpit generates enough heat on its own to stress the driver, even without high ambient temperatures. The rules permit a driver cooling opening in the tip of the nose cone, and in extreme temperatures teams will fit other openings in the hatches on top of the monocoque. There are vents in the helmet to get this cooling air to the driver’s skin without sacrificing fire protection, and modern Nomex race suits are surprisingly thin, allowing some airflow despite their fire protection.
Fig. 1 - Seat belts, a moulded seat and fire extinguisher all tightly packed into the cockpit area (Photo: Craig Scarborough)
Written by Craig Scarborough
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