F1′s war of gears

In the world of F1, gearboxes exist in the shadow of engines and aerodynamics, seldom talked about except when they break.

And yet these modest boxes of cogs do a mighty job, coping with the huge physical demands of transferring power from the engine to the rear wheels and making that power and torque usable and efficient.

They may not be glamorous but that doesn’t mean gearboxes are not remarkable bits of tech. Here are just three gearbox innovations that show engineering ingenuity at its best.

Semi-automatic for the people

We take it for granted that drivers change up and down using paddles on the back of their wheels but it was not always thus, of course.

A simple mechanical lever and a traditional clutch pedal were all drivers had to help them change gears for decades. Although the gearboxes were, by modern standards, pretty agricultural, they were robust.

However, it was easy for drivers to change down a gear too early, and blow the engine – this was by far the biggest cause of engine failure in F1.

Even the gear lever occasionally caused problems: James Hunt’s (pictured) maiden F1 victory, in a non-championship race at Silverstone in 1974, happened despite the knob of his gear lever coming off at the start of the race… every time Hunt changed gear, the lever stabbed him in the hand.

In the 1980s, this all changed. Williams began working on a semi-automatic unit as far back as 1986, according to its engineering guru, Patrick Head. They experimented with using servo-operated valves to change gears rather than the old mechanical linkage to a gearstick.

But it was not until 1989 that Ferrari fitted a semi-automatic gearbox to an F1 car in anger – Williams wouldn’t race with one until 1991.

So why was this new gearbox so important to teams?

It allowed engineers to control the engine speeds at which gear changes took place, eliminating the risk of drivers over-revving by mistake.

It also slashed the time taken to change gear. In a road car, with a manual gearbox, it takes between 0.5seconds and one second to change gear ‘vertically’ (ie 1^st to 2^nd, 3^rd to 4^th etc), and one to two seconds to change ‘horizontally’ (eg 2^nd to 3^rd).

In the 1980s, an F1 driver would change gear in about 0.25seconds – much faster than you or I, but not fast enough, in a sport where success can be measured in thousandths of a second.

The introduction of the semi-automatic box dramatically reduced gear-change times, to between three and five hundredths of a second. In a modern F1 race, a driver may make up to 3,500 gear changes – if you save 0.2 seconds on every change, that’s more than 11 minutes.

Of course, there were fewer gear changes when semi-automatic boxes first appeared – cars ran with far fewer ratios than the eight forward gears and one reverse that F1 cars now feature.

But the difference was remarkable and, occasionally, controversial. Alain Prost, for one, insisted that manual changes should be part of a driver’s skill-set, but he was in the minority – the reduction in engine failures alone meant that manual gearboxes would be quickly become a thing of the past.

CVT – too clever for its own good

Williams were an ideas powerhouse in the early 1990s – they experimented with active suspension, traction control, all manner of clever ways of eking out significant performance advantages.

Having seen how beneficial semi-automatic transmission was, Williams decided to take gearboxes to a new level, and developed a Continuously Variable Transmission system, or CVT.

This was a fully automatic system that did away with traditional gears altogether.

Instead, a system of belts and pulleys would keep the engine within its optimum rev range at all times. This was possible mainly because of the huge leaps in computing power being made, allowing constant monitoring and feedback of engine parameters, driver inputs, wheelspin and suchlike.

One side-effect of the CVT system was that the engine sounded much the same in a corner as it did when flat-out along a straight, as the revs were being kept in a very narrow band.

Williams tested the system in 1993 – you can see videos in which a youthful David Coulthard (pictured), then Williams’ test driver, explains his enthusiasm for the new system.

Alas for Williams, the fully-automatic CVT was a step too far for F1, and it was banned before the team could ever race with their remarkable invention.

Seamless gear changes – as fast as CVT, but with paddles

Various attempts to further speed up gearchanges have been made over the years. A twin-clutch system, for example, was tried but banned.

But teams have worked hard to eliminate almost all the time lost by gearchanges.

As well as saving time, as we saw above, there is a second benefit to minimising gear-change times.

When a car is between gears, it doesn’t lose time just because it’s no longer accelerating. It’s also slowing down.

At higher speeds, an F1 car creates so much drag that it can decelerate at 1g without the driver touching the brake pedal – that’s a pretty big deceleration.

To put that in context, you might experience 0.8g deceleration if you performed an emergency stop in your family saloon.

You can see why F1 cars need to have the slickest of gearchanges.

The solution was to engage two gears at the same time – the gear you want to change out of and the gear you want to change into.

Two separate control barrels are used to allow this – one operates odd gears, the other even gears, and the system relies on the fact that it would take a little time – a very little time – for both gears to engage and lock up the gearbox.

The margins involved are tiny – get anything wrong and the gears will be destroyed in a puff of carbon fibre.

To give you an idea of the sort of computing power that is involved in even a simple system like this, here are some of the procedures for a single gear change from first to second gear.

Firstly, the driver flips one of his gear-change paddles (you can just about see Lewis Hamilton’s 2016 paddles in the picture above) and sends a message to the electronic control system.

This takes a multitude of readings, such as engine speed, clutch position, the speed at which the rear wheels are rotating.

Next, the clutch is disengaged – a valve supplies high-pressure oil to a hydraulic piston, which moves the clutch plates apart.

More valves are used to begin disengaging first gear and engaging second gear – this happens simultaneously, using the two control barrels mentioned above.

The electronic control unit reads the gear position, as well as checking engine speed etc, and won’t engage second gear unless everything is in the right position and rotating at the correct speed.

When all this is done, the clutch plates are closed and the car continues on its way in second gear.

Unless, that is, there’s a problem, in which case the software will try to engage another gear or neutral, to avoid destroying the gearbox or stalling the car.

Complicated, isn’t it? And that happens several thousand times in every F1 car at every F1 race.

But the driver doesn’t even have to take their hands from the steering wheel.

It’s all a far cry from the days of James Hunt having to wrestle with a broken gearstick, and it’s yet another fantastic illustration of how F1 continues to innovate at a remarkable pace.