By Graham Duxbury – Today, every Formula One car features a carbon composite chassis, or a “safety cell monocoque”. How did a plastic material come to replace tried and tested aluminium in the construction of a F1 car?
The answer is centred on the story of the McLaren MP4/1, the first car with a monocoque chassis wholly manufactured from carbon composite material. At the time, many suggested that the MP4/1 was fatally flawed and its chassis would “crack like an egg” in the event of an accident, putting the life of the driver at extreme risk.
In fact, the MP4/1 was tested in a massive crash at Monza during the 1981 Italian Grand Prix. Driver John Watson’s life was certainly on the line that day.
The MP4/1 legend begins with John Barnard and his remarkable imagination and determination as a racing car designer, He honed his skills during stints with Lola and later, in the 1970s, with the Parnelli and Chaparral teams in the US.
As an example of his exceptional work, the Chaparral 2K, an IndyCar featuring ground-effect aerodynamics, won the 1980 Indianapolis 500.
This and other successes in the US brought Barnard to the attention of Ron Dennis, the McLaren F1 team principal and, in 1980, Barnard joined the team.
According to Barnard, his focus was on aerodynamics: “The objective was to optimise it, and that meant using the biggest underwing l could get which entailed a very small section chassis. I wanted to get my chassis down to not too much wider than the driver’s bum.”
For Barnard, the only way to achieve this while retaining the necessary torsional stiffness was to use an entirely new material.
This material was carbon fibre, composites of which were being pioneered in the aerospace industry. The material was light, stiff and extremely strong; perfect – in theory – for a F1 chassis.
Barnard recalls how many in the F1 fraternity “thought we were mad,” saying that a carbon fibre chassis simply would not be safe enough.
While looking for a company to help build his chassis, a contact from Barnard’s IndyCar days pointed him towards the Utah-based Hercules Corporation which had a Skunk-Works-type facility which undertook carbon composites research for the military.
The problem was, this research was classified “top secret” by the US government due to its strategic importance during the Cold War era.
Dennis managed to persuade Hercules that any successes it would have in F1 would not be classified, giving Hercules a promotional platform for its products and public recognition for its achievements.
Barnard presented Hercules with a quarter scale model of his proposed design and soon Hercules set to work. The MP4/1 began to take shape.
The car made its debut in John Watson’s hands at the 1981 Belgian Grand Prix and ran as high as fourth before gearbox problems intervened. He finished third in the Spanish GP, second in France and at the British GP he scored McLaren’s first GP victory in four years. It was the first for a carbon composite chassis.
Key to the MP4/1 missive is the aforementioned huge crash that Watson suffered just weeks later at the Italian GP. The immense impact with a track-side embankment ripped the engine and gearbox off MP4/1’s chassis.
Incredulous fans saw Watson get out and walk away from the steaming, smouldering wreck.
Importantly, the chassis had remained intact and the car had not, as so many sceptics expected, cracked like an egg or exploded into a cloud of black dust.
Watson’s crash and its repercussions continue to reverberate along the pitlane today. Not only did the monocoque design provide unparalleled strength and rigidity, it also allowed the MP4/1 to feature advanced aerodynamics for enhanced on-track performance.
Within months, the design had been copied by many of McLaren’s rivals. which led to a rapid evolution in F1 car construction techniques.
From a technical standpoint, by feeding chassis loads along the axis of the strands in its carbon fibre composite material, the cars were able to boast a higher stiffness-to-weight ratio than those made of aluminium, making them not only lighter and faster but safer too.
Today the MP4/1 is widely regarded as having made one of the largest single contributions to driver safety in motorsport’s history. The principles it established are now mandated in F1’s current regulations.