Where did Red Bull-Honda's pace come from?

I wonder what Mercedes might want the FIA technical department to clarify this week? With altitude at Interlagos coming into play, both the Ferrari and Honda power units had the edge. It wasn't a big advantage, but it was there.

Interlagos is a bit like Spa, in that the first and last sectors are all about straightline speed, while the middle sector is about car grip. In reality, there wasn't much in it either way between the top three teams, as far as top speeds or sector times were concerned. The three are well within the window of what's called set-up compromise.

Red Bull has, without doubt, a very good chassis and with the Honda power unit it seems to have that little advantage when racing at altitude. In Mexico and again in Brazil, which is at around 800 metres, the Honda power unit seems to be a step better than at other circuits closer to sea level.

There can be many reasons for this, but it's probably down to turbo sizing. There will always be a loss of power for any normally-aspirated engine at altitude, but the turbo will make up for most of this. But it does have to work harder than normal.

The regulations define the maximum turbo speed as 125,000rpm, so sizing is critical. When the turbo gets up to near that speed, the MGU-H comes into play by holding the turbo back from over-speeding and, in turn, generating electrical energy, which goes directly to the MGU-K.

In Mexico and Brazil, because of the altitude, there will be less mass flow going through the engine so this means less exhaust gasflow to the drive the turbo. But if Honda's turbo was a smaller unit, it would still reach the maximum rpm even with this reduced exhaust flow.

The process of sizing all these components to work with each other is by no means as easy as just sticking on a different size turbo. Each power unit manufacturer will have a team of engineers running through many thousands of calculations before it commits to anything. The reality of all this is that Mercedes has won every constructors' and drivers' title since these regulations came into play in 2014. This means the Mercedes package, based across the full season, is without doubt the best compromise.

Saying all of that, the Red Bull chassis has also been very good at circuits that are at altitude. You just have to look at its performances in Mexico and Brazil in 2018 - not to mention the fact that Max Verstappen took his first win this season at altitude in Austria. Somewhere along the line, its aerodynamic philosophy works well with the reduced air density.

After having a closer look at the speeds and sector times from each of the top three teams' fastest drivers in qualifying, my conclusions are that they all got just about the best from their relative packages. They are all quick cars, but the Mercedes is probably that little bit less aerodynamically efficient than the other two.

What I would be looking at more closely is the difference in speed at the end of the last sector at Interlagos - so the start/finish line - and the speed trap located 90 metres before the first corner.

Speed gain

Red Bull +5.5km/h
Ferrari +2.2km/h
Mercedes -0.9km/h

For this part of the comparison, I have used the chassis as the reference. The reason for this is to do with the aerodynamic characteristics of an F1 car.

As the car gains speed, the downforce builds up and pushes the car closer to the ground. When this happens, the airflow passing through the diffuser will separate in some areas and this will reduce drag.

To me, it looks like Red Bull has a better handle on this than Ferrari and Mercedes. Its high-rake philosophy might just be giving it more scope to optimise this - especially at high-altitude circuits where the air is a bit thinner.

Mercedes, with its low-rake philosophy, has less mass airflow going under the car and, in turn, probably less rear suspension movement from low speed to high speed. This would give it a smaller window to optimise any diffuser aerodynamic stall, which can influence overall drag.

Mercedes, with its performance, shows that on most occasions it gets it pretty much spot on

It's pretty easy to get an area of the diffuser to stall, but it's not quite so easy to manage it and get it to reattach when the driver hits the brake pedal.

I would have also said the Mercedes DRS was not as effective as that of the Red Bull or the Ferrari. But if you look at the speed at the end of the second sector, it's still not as fast as the other two and you don't use DRS in that area.

When you look at what's happened over the season, the Mercedes cars have scored more points than the others. You get the points in races, and it has had a package that looks after the tyres that little bit better than the other two main contenders.

That comes down to running that little bit of extra downforce, which comes with that little bit extra drag. When Red Bull dominated F1 from 2010-13, its car was far from the fastest on the straight. But the team knew if it could qualify on pole and get a good start, then that would be more or less job done. It became more of a problem when, for some reason, the Red Bulls weren't on the front row.

For Mercedes, it's a bit less of a drama. If it misses out on pole, with the current Pirelli tyres, downforce is a major requirement. It has always been very important to overall performance, but when the teams were running Bridgestones, these had a wider working window and weren't so critical to overheating when the car would start sliding around a bit. But with the Pirellis, just a couple of laps behind another car and you are in trouble.

As I have said many times, the set-up of the car is about compromise. Mercedes, with its performance, shows that on most occasions it gets it pretty much spot on. Sometimes the team slips up, but I do wish it would stop trying to find a 'questionable' reason in what others are doing to account for this. After all, it is racing and all the teams are doing their best to achieve that.

The Brazilian Grand Prix was one of the best races of the 2019 Formula 1 season.

Interlagos is a short circuit, which leads to lots of action but also, because of the nature of the track, overtaking is possible. This shows that a few changes at some of the other venues might just be, if not more important to closer racing than the 2021 technical regulation changes, at least helpful.

I must admit I was bit worried when the safety car was deployed for Valtteri Bottas's engine failure. I suddenly thought that while in the US someone from the FIA must have gone to see a NASCAR race, where a full course yellow is flown if a bird flies over the circuit because it might have deposited something on the track.

It was completely unnecessary as the car was in a safe place on the inside of the track, and at most a virtual safety car would have been adequate. But, no, out came the safety car. This was because of the rule that says if a tractor comes onto the track and is used to lift a car, the safety car must be sent out. But, realistically, it was not really on the circuit. Let's hope a habit is not made of this and that safety cars aren't used to spice things up.

Red Bull, Honda and Verstappen had the upper hand over the whole weekend. No matter what was thrown at them, they took on the challenge and got everything right. And behind, Pierre Gasly backed Verstappen up with second place - yes, there was luck involved, but it was a good drive.

He qualified seventh and started sixth so, as the saying goes, you have to be in it to win it and Gasly was right there for most of the race. This result will be very good for his confidence after what has been a difficult season.

We also need to remember it was almost a Honda 1-2-3, but that was scuppered by what I would call a slightly over-ambitious move on Alex Albon by Lewis Hamilton. Hamilton was on better tyres and would have probably got Albon on the pit straight, but that little bit of impatience cost him a trip to the stewards and instead of a more or less guaranteed second place he got a time penalty and ended up seventh.

As for Ferrari, as they say in Italy it turned into a grande casino. There has been too much of this at Ferrari this season and I'd have loved to be a fly on the wall at Maranello when the morning papers arrived on Monday!

Drivers in the same team must respect each other, or it's costly for everyone

Charles Leclerc passed Sebastian Vettel, who then came back at him on the back straight. A little squeeze from Leclerc on Vettel and a jink left from Vettel and both were out.

I think that both of them were to blame and either of them could have avoided the contact that put them out of the race. The stewards seemed to agree with that. But in these situations, Vettel, even with all his experience, seems to see the red mist too often. Remember what happened with Mark Webber in the 2010 Turkish Grand Prix?

This was no big deal as other than the lesser places, the championships are done and dusted. But some day it will matter - or at least that's what Ferrari is hoping for. If the drivers don't respect each other now, then the same could very easily happen when it really counts.

Mattia Binotto needs to get them together and read the Ferrari rule book to them - plus lay down the ground rules of what's expected of them in the future. Drivers in the same team must respect each other, or it's costly for everyone.

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