How F1's most sophisticated car claimed an era-ending sweep

Racing folk are impatient as a breed. The protracted development of the 1993 Formula 1 championship-winning car began in the summer of 1991, its racing debut was delayed nine months, and there were those within the Williams team who quietly feared it might be found wanting as rivals finally got their acts together. And yet delayed gratification, a concept seldom entertained in F1, would ultimately prevail in the form of 15 consecutive pole positions, 10 fastest laps and 10 race wins.

As Adrian Newey sketched the first outlines of what would become the FW15 on his drawing board, its predecessor was belatedly beginning to pay out on its potential. The FW14 had been quick in the hands of Nigel Mansell and Riccardo Patrese since the beginning of the ’91 season – surprisingly, perhaps, the Italian veteran often enjoyed the upper hand over his team-mate – but reliability was poor. Failures of the new semi-automatic gearbox handed McLaren’s Ayrton Senna what would prove to be a title-winning advantage as he won the first four races of the season, followed by a self-inflicted wound in Montreal as Mansell missed a downshift while waving to the crowd on the final lap.

It wasn’t until mid-June that the FW14 was able to bring home the winning silverware it warranted as Patrese passed Mansell to lead a Williams 1-2 in Mexico. Three weeks later, as Formula 1 visited the unloved Magny-Cours for the first time, ‘Our Nige’ embarked on a winning streak that reignited his championship hopes.

PLUS: The key mistakes behind a lost Williams title 

By then, though, the Williams leadership team were plotting the future – specifically the introduction of semi-active suspension, an improvement on a system the team had tried and shelved in 1988. Although resolving the gearbox issues hogged many resources, test drivers Damon Hill and Mark Blundell were racking up the laps on a mule car with the new suspension. Tentatively Williams planned to run it in a B-spec FW14 at the beginning of the 1992 season and then introduce the FW15, which was designed around more optimal packaging of the reactive system’s components, at the Spanish Grand Prix in early May.

It was a nervous winter for Williams. The team felt McLaren had won the development race over the second half of the year (Mansell even ran without an instrument panel during qualifying at some rounds in a bid to save weight) despite the team’s new wind tunnel coming on stream in summer. Mansell, poorly disposed to reactive suspension after previous experience at Lotus and Williams, wanted no part of the new system, especially when Blundell and Hill reported it gave little feel for grip levels on corner entry.

Mansell was reluctant to adopt active suspension in the winter of 1991, which risked Williams having to abandon its 1992 and 1993 cars

Photo by: Ercole Colombo

Fearing they would have to junk both the FW14B and the new FW15, and race the passively suspended FW14 for the majority of 1992, Newey and technical director Patrick Head emphasised to Mansell that the reactive cars would be his only means of winning the world championship. The FW15 couldn’t run without the system because its aerodynamics depended on it.

Mansell therefore capitulated – and the reactive suspension proved more instantly transformative than expected. The FW14B had so much in hand over cars from rival teams that the sole worry became reliability. At the season opener in South Africa Mansell qualified on pole, 0.74s ahead of Senna, and romped to victory over 34s to the good. Only the top five cars finished on the lead lap. As this pattern repeated in successive GPs Williams decided to set aside the introduction of the FW15 and focus on the FW14B’s reliability, and Mansell claimed the drivers’ title in Belgium, round 12 of 16.

When the FW15 made its debut nine months later than planned, much had changed – hence its arrival in C spec. Most significantly, perhaps, it had a new lead driver.

By reducing pitch, dive and roll, Williams could keep the car’s aerodynamic centre of pressure constant in the way a passive car simply couldn’t

Frank Williams had been quietly courting Alain Prost through 1991 and reached a secret deal for ’93; no wonder Prost had been so unfazed about heading into a ‘sabbatical’ after parting ways with Ferrari two races before the end of the ’91 season. There was now no room for Mansell, since Prost had stipulated they could not work together under the same roof.

Patrese, too, was on his way after struggling to accommodate his style to the reactive suspension’s peculiarities. Hill got the nod as his replacement after much debate among senior management.

Though clearly related to its predecessor the FW15C had been designed from the ground up to maximise the possibilities offered by reactive suspension. It now had power-assisted steering, removing another obstruction to anyone other than Mansell driving it. Besides the better packaging of the mechanical systems, its aerodynamics were optimised within the finely controlled window of ride height permitted by the electronics.

By reducing pitch, dive and roll, Williams could keep the car’s aerodynamic centre of pressure constant in the way a passive car simply couldn’t. As on the previous system developed with AP, the Williams reactive suspension replaced conventional springs and dampers with hydraulically actuated rams.

The difference was more sophisticated – computerised rather than mechanical – management of the hydraulics via Moog servo valves at each corner which offered faster, more finessed responses. Steve Wise, the team’s head of electronics, had evolved a new control module built in-house and Paddy Lowe had joined him to work on the control software.

Prost and Hill made full use of the FW15C's advancements to dominate the 1993 season

Photo by: Motorsport Images

As on the FW14B, the FW15C featured a button on the steering wheel which could lower the rear ride height, stalling the diffuser and reducing drag for a straightline speed boost. But it no longer had dials enabling the drivers to tune the car’s ride height for low-speed and high-speed corners: telemetry technology had progressed to the point that the car’s electronics knew where it was on the circuit and could set these parameters to their optimal levels without driver input.

All in all it was a faster car. Although the FIA had introduced some measures to slow cars down, including narrower wheels and track and a ban on front-wing endplate ‘skirts’, the FW15 sliced through the air more efficiently than its predecessor.

Superior aerodynamics aside, the FW15C also gained power-assisted brakes with a four-channel anti-lock system (introduced at the French GP). New conrods and a revised combustion chamber design in the Renault RS5 engine yielded even greater power from what was already Formula 1’s most powerful V10.

Even before pre-season testing, Williams had reason for confidence. Although key rivals had been working on their own reactive suspension systems, they were behind the development curve and had less useful engines. Following Honda’s withdrawal, McLaren was engaged in a bunfight with Benetton over which spec of Ford engine it could obtain; in any case the V8 had less grunt than Renault’s V10. Ferrari’s reactive suspension, meanwhile, appeared to come with a built-in poltergeist.

Williams continued to push development of electronic driver-assistance technology, testing a system which would eliminate gearchanges entirely. Continuously variable transmission (CVT) wasn’t a new idea but it had never really caught on in the automotive industry.

Pioneered and patented by the Dutch engineer Hub van Doorne of the truck and bus manufacturer DAF, the CVT gearbox provided a USP for the company’s new range of small four-seater cars, beginning with the DAF 600 in 1958. Known as the Variomatic, the ’box drove via a belt and two variable-diameter pulleys, enabling stepless changes of effective gear ratio: altering the diameter of the pulleys in sync, one narrowing while the other widened, enabled the one driven by the engine to maintain a constant speed while the other’s rotational velocity changed. This made for a slightly disconcerting driving experience since the engine revs remained constant at peak torque while the car accelerated.

While CVT was widely adopted on mopeds there was little interest among mainstream car manufacturers, perhaps because of its association with DAF’s quirky little economy cars. When Volvo bought DAF’s car division in the 1970s it wasn’t interested in CVT and the patents were transferred to another company, Van Doorne Transmissie. As Williams readied its own system for use – in partnership with the Dutch company – the only mainstream car on sale in the UK with CVT was the Fiat Punto Selecta.

Test driver David Coulthard completed a number of runs in a CVT-equipped FW15C, one of which – at Pembrey – was filmed by a Discovery Channel camera crew. The footage is all that remains of the project since the FIA moved to ban such systems before work on it was complete. Whether it would have made the car faster is open to conjecture. Coulthard thinks it would, since there was no break in power delivery (seamless-shift ’boxes were 14 years away) but, since the team hadn’t yet reached the point of making back-to-back comparisons in the same running conditions, it’s impossible to say for sure.

Advancements in telemetry meant the FW15C always knew where it was on track and adjusted its suspension settings accordingly

Photo by: James Mann

Despite the horsepower deficit, and a supposedly wavering commitment to McLaren – he would only countenance a race-by-race deal – Senna took the battle to Prost in a remarkable fashion during the 1993 season. For all the FW15C’s superiority, emphasised by Prost and Hill claiming 15 poles in 16 races, whenever Alain fluffed his lines the vivid yellow crash helmet of his old adversary was always in close attendance.

And there were several slips twixt cup and lip – not least at the European Grand Prix at Donington where, in typical British spring weather, Senna was in a class of his own while the usually canny Prost read the conditions poorly. For all that the FW15C was garlanded with assistance technologies, Prost often struggled to get away from the line cleanly, particularly at Monaco where he jumped the start and then stalled when leaving the pits after serving his penalty.

Nevertheless Prost seemed to have the championship well in hand until a mid-season run of misfortune – a rear-wing problem in Hungary, a slow pitstop in Belgium, and an engine failure in Italy – sapped his momentum slightly. At round 14 of 16, the Portuguese Grand Prix, he finished second to Michael Schumacher’s Benetton and that was enough to put the title beyond anyone else’s reach.

1994 would supposedly represent a competitive clean sheet while the FW15C, still perhaps the most technologically sophisticated F1 car of all time, would take its place in the Williams museum

By then, though, Prost had already announced his retirement, half way through his two-year contract. It was said his enthusiasm for F1 was beginning to pall in the face of supposed victimisation by the FIA and its president, Max Mosley. That March he had been summoned before a tribunal for making vocal criticisms of the governing body, and on more than one occasion he had been penalised for seemingly arbitrary reasons while blatant examples of poor driving by others were ignored.

Equally significant was the arrival of Senna at Williams for 1994, at that point only a strong rumour but one which was confirmed a fortnight after Portugal. After their rancorous relationship at McLaren, they could not work with one another again – although Senna was among the most disappointed to see Prost depart. He was the driver Senna had always measured himself against, the one he felt driven to defeat. The photograph of the podium at the season-ending Australian GP communicates this poignantly: second-placed Prost is all smiles, victorious Senna is downcast and lost to introspection.

It was the end of an era. Mosley made it his personal mission to put an end to what he called “driver aids”, believing them to be corrosive to sporting purity as well as elevating car performance to dangerous levels. In June he had announced plans to outlaw such technologies from 1994, enshrining in the rulebook a phrase which endures to this day: “the driver must drive the car alone and unaided”. Engineers and some drivers threw up their hands in horror but even the famously ballsy Gerhard Berger must have given thanks for the forthcoming ban when, as he accelerated out of the Estoril pits in his Ferrari, its rear suspension dumped the car on the ground and he spun across the path of others travelling at racing speed.

Prost bowed out at the season's end with a fourth world title, as F1's 'driver aids' were banned in a true end of an era

Photo by: Sutton Images

Williams didn’t race the CVT but Benetton ran its Pat Symonds-designed four-wheel steering system in the last four rounds of the season. 1994 would supposedly represent a competitive clean sheet while the FW15C, still perhaps the most technologically sophisticated F1 car of all time, would take its place in the Williams museum.

Events of the following season would demonstrate that, while the rulemakers could eliminate technologies at the stroke of a pen, they could not do the same for the risks inherent in high-speed competition.

 Race record

Starts: 32   
Wins: 10 
Poles: 15   
Fastest laps: 10  
Podiums: 12   
Championship points: 168

Specification

Chassis: Carbonfibre monocoque
Suspension: Double wishbones with pushrod-actuated, computer-controlled hydropneumatic rams  
Engine: Naturally aspirated Renault RS5  
Engine capacity: 3493cc   
Power: 780bhp @ 13800 rpm  
Gearbox: Six-speed semi-automatic 
Brakes: Carbon discs front and rear   
Tyres: Goodyear 
Weight: 505kg  
Notable drivers: Alain Prost, Damon Hill

Arguably there has not been an F1 car as complex as the FW15C since its active suspension was banned

Photo by: James Mann