Why F1 cars have all gone size-zero

One day we'll all live in a world where smartphones and tablets will be as thick as a sheet of paper. With the rise of nanotechnology in the electronics sector, components now are so tiny you can't see them with the naked eye - sending heavy, unwieldy consumer products to their deaths.

In a largely mechanical sense, Formula 1 has followed a similar path. Designers and engineers alike are joined in pushing current technology to its limits, making components smaller, lighter and more powerful.

Over the past 20 years F1 cars have become increasingly shrink-wrapped, especially around the engine cover, as the internal components are arranged with the same intricacy as a Swiss watch. Giorgio Piola's illustration of the 2018 Williams neatly shows just how narrow contemporary designs have become at the rear.

Of course it would be easier for the teams - in the name of reliability, at least - to have plenty of leeway with how they package components. If they didn't have to position everything so closely together, they wouldn't have to expend so much effort mitigating the effects of the heat from the power unit components on other associated parts.

But the demand for all internals to be nestled together like sardines comes from the ever-increasing desire to be aerodynamically efficient, and slashing the amount of bodywork ensures that a car can slip through the air more optimally.

That's just like the world of consumer electronics, where external demands - in this case, the need for phones, tablets and the like to be portable and intuitive - influence the design and arrangement of the components inside.

Since their introduction in 2014, the turbo-hybrid power units have also been subject to a similar trend in development. By the end of the V8 era we were seeing some of the tightest packaging solutions ever, particularly in the case of Red Bull and Williams (to varying degrees of success).

Now, after five seasons of progress with the current engines, we're fast approaching similar levels of corset-tight bodywork. There's a colossal shift in the way things are packaged compared with how they were just a few seasons ago, perfectly demonstrating the level of progress being made.

Compare any one of 2019's fleet of machines with those that kicked off the turbo-hybrid era, and it's like comparing a svelte eagle to a portly pigeon.

The increased cooling requirements of batteries, intercoolers and motor generator units, as well as the newly turbocharged internal combustion engine, resulted in an initial uptick in puppy fat back in 2014 - especially on the Renault-powered cars, where cooling was a huge concern to begin with.

Now everything's so tight that the FIA-mandated deformable structures at the sides of the car are the widest points of the bodywork, doubling up as aerodynamic devices such as turning vanes, and other pieces are placed aft of the front wheels - as you can see from Giorgio Piola's illustration of that area of the new Ferrari.

One of the key developments in this area has been the positioning of the sidepod inlets, and these being moved as high as possible. Not only does this reduce the frontal blockage to the inlet from the suspension components, it also encourages careful positioning of the radiators within the sidepods. Old racing truisms remain in place, and positioning heavy components as low down in the car as possible trades off with the desire to place the inlets high up.

It does a disservice to Mercedes' carefully manicured packaging to call it bulky, especially as the team has employed small bulges at the rear of the car to afford any engine mountings a little bit of clearance

Within an F1 car's sidepods, the radiators are angled downwards from the inlet, forming the crease along the widest part of the bodywork. There's some dead space around the underside of the radiator that can be exploited by creating an undercut around the bottom of the inlet. This works as a channel for airflow around the bargeboards to be guided around, and the reduced journey made by the air minimises overall separation, as the skin friction of the bodywork stops the momentum of the air particles at the boundary layer.

From there it's up to the designers to stuff as many parts into the smallest nooks and crannies as possible. True to form, Red Bull probably boasts the tightest bodywork around, continuing to follow Adrian Newey's vision of vacuum-packing the internal components to minimise overall drag.

Red Bull's sidepod inlet is tiny, placing a little more reliance on the overhead airbox - another trend in trimming all excess from the bodywork. Resembling a letterbox, the inlet is bounded at the bottom by the side impact structure, lending a more tapered undercut into the front of the sidepods that blends around the tightly packaged midriff.

Crucially, the sidepod barely curves out before folding into the rear of the car, tucking in neatly and tightly below the flared bodywork used for cooling. In having these tiny sidepods, the team also has a lot more control over airflow passing over the top. Reducing the amount of undercut at the rear means air is able to pass over the bodywork and drop neatly onto the floor, developing a greater pressure differential at the point at which the diffuser starts.

This is rooted in what's known as the Coanda effect, which is the phenomenon experienced when a fluid remains attached to a convex, curved surface. Run the back of a spoon under a tap and you'll watch the water follow the surface. It's a principle that a number of teams follow and, for the second week of pre-season testing, it's something Mercedes has also tried to exploit further - as shown in Giorgio Piola's image below.

It does a disservice to Mercedes' carefully manicured packaging to call it bulky, especially as the team has employed small bulges at the rear of the car to afford any engine mountings a little bit of clearance. But the updates brought to the second week of testing noticeably tightened up the launch-spec version, adding a small channel to the point at which the sidepods tapered in to more comprehensively move airflow to the floor section and around the undercut at the rear. Again, this simply aims to encourage a little more performance from the diffuser, enhancing that pressure differential, while also working with any further ancillaries to seal the diffuser and bolster rear-end downforce.

Mercedes is the only team on the grid to employ a different inlet design, using the deformable crash structure at the top of the sidepod and positioning the apertures lower - clearly not suffering any ill effects from any potential front suspension blockage.

The remainder of the field uses the high inlet, but still works towards the tight rear bodywork to augment the performance of the floor components. In that, it underlines the slowly convergence between the engine suppliers; even Honda and Renault, previously troubled by the turbo-hybrid setup, have been able to push the bounds of cooling and pursue greater risks in the hunt for tighter bodywork.

This approach to the inlet position was pioneered by Ferrari in 2017, leading a number of teams to trial the solution last year. Ferrari continues to use an extended inlet along the top face of the sidepod, managed by the flank-mounted winglet over the top of the sidepod geometry to bolster the cooling.

There's further variation if you look a little closer. Although Haas's approach to bodywork is strongly rooted in Ferrari's developments, especially proven by this year's tighter engine cover (which suggests the intercooler has been relocated), the sidepods display a more pronounced undercut compared with the rest of the field. On the other end of the spectrum, McLaren's sidepods are barely bothered by any kind of undercut, being almost trapezoidal in shape to minimise the path taken by the oncoming airflow.

If the formula doesn't change and the current rate of development continues, there's the potential to shrink the bodywork even further

That's quite similar to Alfa Romeo's development path. It opted for a solution last season that stood out among its counterparts, while Racing Point operates on a similar line to Haas, albeit with a marginally-larger engine cover to trade off in the cooling stakes. In that, it's different to Mercedes and fellow customer Williams, which both use the downwards-sweeping crease in the bodywork to move the airflow along.

As these turbo-hybrid engines continue to be developed, and the cooling requirements become ever reduced thanks to efficiency gains in the internal combustion engine and the turbocharger, teams will have greater latitude in being able to compress the internal components further. The size of the components will also drop, and the advances in battery technology - currently being pushed to the limits by Formula E and greater research into fluoride-ion cells - will condense the energy store.

If the formula doesn't change and the current rate of development continues, the bodywork will continue to shrink, offering all the associated aerodynamic benefits. It's amazing how such a complex engine formula can be taken to those extremes in packaging, although whether the mechanics have any fun assembling the car under such tight tolerances is another question indeed.