The secrets that show Mercedes F1 power is still king

Tucked away behind some discreet landscaping on the otherwise nondescript A508 connecting Northampton with Leicester, and sharing a roundabout with a household waste recycling centre, is the home of Formula 1's most successful turbocharged hybrid engine.

Mercedes-Benz High Performance Powertrains began its life in a nearby industrial unit, but this facility is something else: neat architectural details mask the wheels of its industry.

"It's not a factory, it's a campus," says managing director Andy Cowell. "It's - hopefully - a nice environment that people enjoy coming to. It's challenging - there are tough technical activities, tough problem-solving, hard graft.

"But we treat everybody with respect and try to look after their health with good food and exercise."

Indeed, one of the four main buildings on the Brixworth campus is a huge gym, and the comestibles dispensed by the on-site canteen are reputedly the envy of the wider Mercedes F1 organisation. This is a business that doesn't take its employees for granted - and nor should it, because Mercedes' present success is built on a foundation of great pain.

After Mika Hakkinen's back-to-back drivers' titles in 1998 and '99, the McLaren-Mercedes partnership struggled to recapture the magic. Often the engine was the guilty party in on-track failures, even though the company began to focus its efforts solely on F1.

It was a make-or-break period in the middle-2000s that persuaded Mercedes to invest in a way that would not only enable it to winkle out the reliability problems, but also to accelerate past its rivals in development for the coming hybrid technologies.

It's well-known Mercedes had a single-cylinder research model for the V6 turbocharged hybrid regulations running as early as 2011, more than two full seasons before the rules came into force.

"You have to go back to 2005," says Cowell. "That was when Mercedes decided all the V8 activity was going to be done here in Brixworth - which required extra dynos to be installed, including a single-cylinder - and the activities based in Stuttgart would be closed down, with some of the expertise coming here. 2004 had been a horrible season with lots of finger-pointing internally. There were 400 people here and 200 in Stuttgart, all just working on a V8 for McLaren.

"That's when Ola Kallenius [now chairman of Daimler AG] was appointed as managing director and said we were going to do all the F1 naturally aspirated V8 development here.

"When the KERS [Kinetic Energy Recovery Systems] regulations came out, Ola said, 'That's a powertrain topic - Mercedes should invest in that technology at Brixworth.' And you end up with a 60-kilowatt electric motor, an inverter [the control unit for the motor], cell technology being developed with A123 [a specialist battery manufacturer] and HPP understanding how to put that into a battery, plus that single-cylinder test bed.

"So, when the new [2014] regulations came out we had the infrastructure and the expertise [in place].

"We put a turbocharger gas stand in as a new capability and got on with it while our V8 and KERS system was regarded as just about the best - and it was reliable, so it wasn't sucking in lots of resource. All of our problem-solving resource could go into the new stuff."

Throughout 2012, when Mercedes started to pick up race wins as a constructor in its own right as well as with McLaren, the view internally was that the KERS-equipped powertrain was competitive enough to justify directing engineering-innovation resource elsewhere (the Mercedes KERS was designed and built in a Portakabin on site, now repurposed for storage).

Even in 2013, when outsiders regarded Mercedes' haul of three race wins as inadequate in comparison with Red Bull's 13 (including nine consecutive victories for Sebastian Vettel), Brixworth maintained its belief that the following season would be the big opportunity.

Throughout the hybrid era the Mercedes power unit has been the one to have, even after the aerodynamic regulations were overhauled for 2017.

That change was largely a response to Mercedes' superiority, and the perception (magnified by angry noises-off from the likes of Adrian Newey) that the powertrain was too great an arbiter of performance.

Statistics in the three seasons since - including yet another regulatory tweak directed partially at clipping Mercedes' wings - suggest that rival manufacturers still have some ground to make up.

But Cowell insists power unit performance is converging.

"The technical regulations have been fixed, so it gets harder going over the same ground," he explains.

"
I think our development curve, the power unit we introduced in Melbourne [last year] was a good step [over 2018]. Throughout 2019 our qualifying pace hasn't improved, but our race pace has improved with regards to the powertrain contribution. Ferrari, Renault, Honda, they're very close.

"Was it three years ago in Abu Dhabi there was the statement that 'We [F1] want naturally aspirated V8s again' and standard engines?
 I remember going to a meeting and being told that was the way forwards.

"It was a big gathering. Bernie [Ecclestone] was there. The dinosaurs were all aboard the SkylArk at that point..."

As Cowell permits himself an eye roll, F1 Racing racks the mental archives in search of that delightfully recherche cultural reference. Noah and Nelly in SkylArk was a 1970s BBC cartoon riffing on the Noah's Ark story, narrated by Richard Briers.

"The team principals were complaining that the power units were contributing too much to the performance differentiation of the grid," Cowell continues. "The manufacturers got together and said 'Leave the technical regulations as they are and it will close up'. And it has closed up.

"We look at the end-of-straight speed of the cars and we hate it if we're not the quickest. 


"You want to be the provider who gives the driver the easiest time on the straight. That's what we love doing and we get such a kick from the commentator saying 'Look at the power of the Mercedes'. We get quite a lot of pain when it's the other way around.

"We get a lot of pain when Lewis comes on the radio and says 'I need more power'. You've got it all, mate!"

In the foyer of the F1 engine facility - the mirror-image building opposite focuses on hybrid tech, with half an eye on forthcoming road cars - two turbocharged hybrid Mercedes power units in glass cases flank the entrance.

What's instructive is that while it's easy to assume that successive generations of the Mercedes PUs flow and evolve from one another, these two differ greatly in size and detail.

One is from 2014, the other 2018. The later one is actually taller as a complete unit including the airbox, thanks to 2015 rule changes permitting variable air intakes. It's also packaged differently in terms of where the ancillaries are located, a measure of how every nuance of an F1 car changes from season to season.

Brixworth's integration with the chassis factory at Brackley is famously tight and this is a powerful factor in the race team's success.

The powertrain engineers are eminently willing to compromise on design features - even if that means lowering the horsepower ceiling - when aero gains resulting from that trade-off yield better results.

"We work collectively on lap time," says Cowell, "That means every idea, whether it's generated in this location or Brackley, is equated to lap time in milliseconds. We look at what will make a car quickest over a race lap. Our durability is a given, so we put a lot of engineering resource on the powertrain into things that might not make Lewis smile as he goes down the straight but should make him smile as he goes round the corner.

"That's an element that perhaps the powertrain doesn't get much credit for. There are things we're doing with the cooling, so that the package can be as tight as possible, and the ducts can be as small as possible, for the benefit of the aerodynamics - which is king, given the evolution of the regulations of the past few seasons.

"It's rare that we say, 'There's something we'd like to do but we can't fit that in this year's car'. Occasionally it happens but it's rare. One in 10 of those ideas have to wait. And generally those ideas need quite a long time to develop - if you're tearing the system up that much it will typically take until next season to make sure that the idea will really make the car quick. Engineers' first calculations never quite match up with the reality of what you actually see on the dyno or on track. Our heads work with a variable scale - we ignore the inconvenience of mass and volume sometimes, when we have these wild dreams..."

While Mercedes' long-term commitment to F1 - along with that of its rivals - remains in doubt beyond 2021, there's little evidence of activity at Brixworth scaling back.

Quite the opposite: the recently built Hybrid Technology Centre includes a four-wheel drive dyno for future projects including the Mercedes-AMG One, a limited-edition 1000bhp monster with an electrified front axle.

Production is due to begin this year, and the headcount at Brixworth will expand as the design and engineering effort shifts towards manufacture of the powertrain.

F1's forthcoming budget cap will also have an effect, since it mandates reduced dyno activity and ERS running. But Cowell cautiously suggests that might have a beneficial effect on development rather than curtailing it.

"Talking to the guys who have experienced this sort of regulation on the windtunnel, they've quite enjoyed the journey," he says. "You have to think more before you start, make sure it's good quality. That's healthy, good productivity stuff.

"So I don't think it will slow down our rate of development. It may improve because the quality of the tests we do will be better. The accuracy of the data will have finer resolution.

"Our upfront computer-aided engineering will have to be stronger such that it is closer to reality. It's a change we need to make over the next 13 months."

Although pushing the boundaries of engine development within stable regulations is "bloody hard", Cowell reckons Brixworth can carry on unlocking performance and efficiency.

After all, we now take the 50% thermal efficiency of F1 engines for granted. Ten years ago it was viewed as unobtainable and 40% was thought to be overly optimistic. Mercedes began 2014 with 44%.

While these figures don't necessarily trigger visceral excitement among non-engineers, they suggest anything is possible given time, ingenuity, investment, and the right working practices.

"Engineering is a creative business," adds Cowell. "To innovate and be a pioneer you have to be brave and bold and sit in a sandpit wearing a Hawaiian shirt with fluffy creativity all around you.

"But to prove something is good for racing, to do the analysis when there's a failure, you need to be process-oriented and robotic. Don't tell me what you feel - what does the data say? Don't give me an adjective, give me numbers.

"Let's not assume there are boundaries to what we can do in terms of combustion speed, friction reduction, managing the energy flows through the power unit. Let's assume there are no boundaries and just keep on innovating.

"In some industries it's all about improving the cost. We've got the purity of improving the science. It's a nice reward..."

The birth of a titan

A little over 200 metres down the road from the Mercedes-Benz High Performance Powertrains campus, Ilmor Engineering still plies its trade in an industrial estate on the outskirts of Brixworth.

Founded by US motor racing magnate Roger Penske and Cosworth engineers Mario Ilien and Paul Morgan in 1983 to develop engines for IndyCar, initially with General Motors backing, Ilmor expanded into Formula 1 in 1991.

The Leyton House chassis was perhaps not the best advert for Ilmor's V10 but by 1992 Tyrrell had taken up an engine supply as well. At this time Mercedes had been planning to return to the F1 grid after a hiatus of nearly 30 years in a joint venture with its sportscar partner Sauber, but its commitment wobbled as the global economy slid into recession.

Sauber ploughed on regardless with low-key support from Mercedes and obtained a supply of Ilmor V10s for its debut in 1993. Carrying 'Concept by Mercedes-Benz' on their bodywork (and Sauber logos on the engines' cam covers), the cars exceeded expectations.

Mercedes reacquired its corporate nerve and began to invest in Ilmor, buying General Motors' 25% stake and taking naming rights on both Sauber's V10 and a top-secret engine Ilmor had been researching for Penske's Indy 500 assault.

Believing Sauber was inadequate to the task of delivering a race-winner, Mercedes formed a partnership with McLaren in 1995 that soon delivered two F1 drivers' championships.

But its interest in US racing fizzled out at the end of the decade. After Morgan's death in a plane crash in 2002 Mercedes increased its stake in Ilmor to 55%, and in 2005 it bought out the company entirely and renamed it Mercedes-Benz High Performance Powertrains. Ilien and Penske acquired the special projects division, which retained the Ilmor Engineering name.