The Mercedes W04 rolled out at Jerez ahead of pre-season testing for a private filming session. Much to the surprise of many the car ran in front of the media before its formal launch.
Once the car had been properly launched it gave an opportunity to get a closer look at what appears to be very much an evolution of the W03.
At the front the car employs the vanity panel found on most of the current generation of F1 cars, though a slight hump is still evident. Note the strake along the side of the nose, also evident on the Force India.
Mercedes has chosen to continue with pushrod actuated front dampers, whilst McLaren and Ferrari have both gone the pull rod route.
A nice look at the front brake ducts, expect a lot of development in this area, the air temperature at Jerez is relatively low so cooling is not a critical factor.
The W03 sports an interesting set of turning vanes around the sidepod, with three Ferrari style winglets under the wing mirror stalk, two turning vanes on its upper edge and the now commonplace sidepod turning vane on the side.
The sidepod itself has a slight upwards flick at the outer edge.
The exhaust is typical of the designs fitted to cars in 2013, it does however feature some cooling gills just inboard of the exits.
At the rear end pull rod suspension is retained whilst the sculpting under the exhaust exit is of interest.
TEST 01: JEREZ
Chassis: Not disclosed
Ross Brawn: After a difficult first half of the test, the last two days have really been as good as we could have hoped for. Nico is probably best placed to compare between last year’s car and the new W04 and he seems pretty enthusiastic, but it is hard to have any reliable feeling of where we stand relative to the competition. Lewis had a very constructive day today as he settled in to the car; he has been very straightforward in telling us what he thinks, is interested in everything about the car and has a very good eye for detail. Overall, the step we have to make from where we were at the end of last year is substantial and it is also, of course, a moving target. But looking at the team as a whole, I can see very encouraging signs of progress.
As you can see from the image above the first day of testing did not go all that well for Mercedes. An electrical problem stopped the W04 in spectacular style
Unburnt fuel in the exhausts ignited but did not cause any serious damage to the car according to the team. The cause was found to be a fault in the wiring loom which has since been modified. However Mercedes is thought to be using an innovative wiring solution on the W04 with the loom running through the bodywork instead of under it as normal. This has not been confirmed yet.
The opening test gave a first look at the cars diffuser. In the image below you get an idea how complex the aerodynamic flow structures are in this region. Mercedes made a significant upgrade to its facilities mid way through last year, a 60% scale wind tunnel model was used to design the W04, whilst a 50% model was used for the W03.
A chat with Mercedes Press Officer Bradley Lord reveals a little bit more about the wiring harness on the W04, whilst he did not know if Mercedes had changed supplier he described the loom as such “I’m pretty sure it is the same as last year, we have all the wires in a carbon fibre housing with connectors on rather than in the usual heat shrink, it is lighter that way. Otherwise it is just a conventional loom.” Lord went on to explain that it was the same as the W03 was fitted with as far as he knew.
Despite some components being modified following the fire on the W04 the car still shows clear signs that it is getting far too hot.
When the W04 is not fitted with its rear wing stalling device (more on that to follow) there is a curious vertical element hanging off the centre of the rear wing. Its purpose is not clear.
At Jerez Mercedes tested a new five element front wing
TEST 02: BARCELONA
Chassis: Not disclosed
Mercedes evaluated some new components at the rear of the cars floor.
A look from above at the rear of the W04 gives an idea of how Mercedes is channelling its exhaust plume. The strake running along the floor seems to fence off the flow from the rear tyre. Note the cooling gills inboard of the exhaust channels, compare with an earlier version of the same part
In this version there are some other areas of interest, note the light brown patch on the floor and the spider web of sensor cables above the diffuser.
A look at the diffuser of the W04 as fitted at Barcelona reveals some monitoring equipment, note the section shrouded in foil and the hole in it.
On other runs different sensors were run on the rear of the W04 much of this is thought to be about getting a better understanding of the exhaust plume.
In a curious move Mercedes tested a non Coanda effect exhaust at Barcelona. Quite why the team would do this is not clear.
A flow vis run reveals the impact of the front wing on other parts of the car. Note how air from the front wing licks the suspension members, wing mirror and rear wing.
A small air speed array was fitted to the rear wing end plate of the W04.
TEST 03: BARCELONA
Chassis: Not disclosed
The F1 W04 has completed 5224 km over the three tests.
“With the conclusion of our testing programme, I am pleased with the progress that the team has made over the last month and the steps forward that have been made with the car. We have achieved our objectives for the test programme and the mileage that we have been able to complete has been very satisfying. Lewis has settled into the team extremely well and everyone has enjoyed working with both him and Nico throughout the three tests. We now have one final week back at the factory to complete our preparations; both drivers will be at the factory this week and, as always, there is a lot of work to do in a short space of time. We’re realistic about our performance here and our position once we get to Melbourne, and we look forward to the challenge of a new season ahead” – Ross Brawn.
A look at the support-less splitter on the car, not the raised forward elements.
A very large sensor array was run on the car to study the airflow behind the front wheel an area of particular interest to the team with the three pointed star.
RACE 01: ALBERT PARK, MELBOURNE, AUSTRALIA
Car: 10
Chassis: W04/04
Result: DNF (electrical)
Car: 09
Chassis: W04/03
Result: 5th
Ross Brawn: We had a very good opening stint of the race, making the supersoft tyre last until lap 13 for Lewis and lap 14 for Nico. That convinced us that a two-stop strategy was feasible this afternoon. However, the balance on the medium tyre was not what we needed. Having committed to two stops, and adjusted our pace accordingly to preserve the tyres, the decision to convert to a three-stop strategy compromised Lewis relative to those cars who had gone for three from the start. The behaviour of the tyres is something we will have to think about and understand over the next days. Nico was running strongly when he was forced to retire. We saw a drop in voltage from the battery and that stopped the car. Overall, we have made a good step with the car and learned a lot this afternoon. If we can put the pieces of the puzzle together, we have the ingredients to race well.
RACE 02: SEPANG, SELANGOR, MALAYSIA
Car: 10
Chassis: W04/04
Result: 3rd
Car: 09
Chassis: W04/03
Result: 4th
A good look from an unusual angle at the front wing of the W04, not the small strakes and the way the elements sit together.
A look at the cars diffuser was also afforded in Malaysia.
RACE 03: JIADING, SHANGHAI, CHINA
Car: 10
Chassis: W04/04
Result: 3rd
Car: 09
Chassis: W04/03
Result: DNF (suspension)
Ross Brawn: We didn’t quite enjoy the balance with the car today that we were expecting. Clearly the track had moved away from us and perhaps more towards one or two other teams. Certainly we didn’t have as good a balance in the race as we had on Friday. With Lewis, we did the best we could with the car we had today and he drove extremely well. We needed to keep the stints as evenly balanced as possible to make sure we had adequate tyre life, however, even with that, it became very close with Sebastian at the end. Nico was running with the same issues a few places back when a problem with the rear anti-roll bar meant we had to stop the car. Overall we can be confident that we’ve made another step forward this weekend, and the fact that we’re all a little disappointed with third is a measure of the ambition and expectations of the team.
Mercedes ran a revised front wing in China. Compare the inner part of the upper element on the old wing (above) with the new (below)
RACE 04: SAKHIR, BAHRAIN
Car: 10
Chassis: W04/04
Result: 5th
Car: 09
Chassis: W04/03
Result: 9th
Ross Brawn We struggled badly in the early part of the race when the track temperatures were at their highest. This is an issue we have to address and we will continue working on solutions to improve our performance in this area. In the second half of the race, as the track temperatures cooled somewhat, our pace was not bad – particularly with Lewis. We got two cars home in the points, both drivers enjoyed some exciting wheel-to-wheel racing and the pit crew delivered some great stops. Lewis and Nico did as good a job as possible with the car we had this afternoon but it was a case of damage limitation for both of them. However we must make it a priority to cope better with elevated temperatures: the tyres are the same for everybody and we are not performing as well as our competitors in these conditions.
RACE 05: MONTMELO, CATALUNYA, SPAIN
Car: 10
Chassis: W04/04
Result: 12th
Car: 09
Chassis: W04/03
Result: 6th
Ross Brawn: We endured a very difficult afternoon and the comparison between our competitiveness in qualifying and in the race was particularly disappointing. Nico did an excellent job managing the tyres to make just three stops and his level of performance showed what our car is currently capable of on tracks like this. Lewis didn’t have a good balance at any point and that simply made a critical situation worse, which forced him to convert to a four-stop strategy midway through the race. We must find the key to why we are losing performance on Sunday afternoon and find the right solutions to improve.
RACE 06: LA CONDAMINE, MONTE CARLO, MONACO
Car: 10
Chassis: W04/04
Result: 5th
Car: 09
Chassis: W04/03
Result: 1st
Mercedes was in the news at Monaco due to a protest over a post Barcelona tyre test.
Red Bull and Ferrari lodged an official protest against Mercedes over what they deem to be an illegal tyre test held at Barcelona. The British based German team ran for three days at the Circuit de Catalunya after the Spanish Grand Prix. Over 1000km was covered.
Three teams, McLaren, Ferrari and Red Bull believe that the test breaches article 22.4 of the 2013 FIA Formula 1 Sporting regulations which states that; No track testing may take place between 1 February and the start of a ten day period which precedes the start of the first Event of the Championship of the same year
with the exception of;
Three team tests of no more than four consecutive days duration, carried out on a site approved by the FIA for Formula 1 cars (the three preseason tests at Jerez & Barcelona – RCE).
One three day young driver training test carried out on a date and site approved by the FIA following consultation with all teams. No driver who has competed in more than two F1 World Championship races may take part in this test and all drivers must be in possession of an International A Licence.
Four one day aerodynamic tests carried out on FIA approved straight line or constant radius sites. Any of these days may be substituted for four hours of wind-on full scale wind tunnel testing to be carried out in a single twenty four hour period.
If a team declares that one of its current race drivers is to be substituted by a driver who has not participated in an F1 race in the two previous calendar years, one day of track testing will be permitted between the start of a ten day period which precedes the start of the second Event and the last Event of the Championship.
Whilst Mercedes has made no formal comment about the test yet it is believed that it was conducted on behalf of Pirelli which wanted to test its new tyres which it hopes to introduce at the Canadian or British Grand Prix. It has been reported that Mercedes believes that the tyre supplier can call on one team to conduct a private test if the circumstances require it. But there is no such provision in the Sporting regulations for this, however it is believed that there is a clause in Pirelli’s tyre supply contract to allow for this which over-rides the sporting regulations.
“In the World Rally Championship contract it’s exactly the same. We can do it with a representative car” Paul Hembery claimed. “We’ve done it before with another team and we’ve asked another team to do some work as well. In reality we were looking at next year’s solutions and trying a variety of different things, Mercedes haven’t got a clue what on earth we were testing in reality. It was 90 per cent for next year. We only changed at the last minute. The bottom line is we’ve been trying to find a way to test.”
Despite complaining about the Mercedes test it has been reported by Joe Saward that Ferrari also conducted a secret test for Pirelli following the Bahrain Grand Prix .
It has been suggested that this test was run using a 2010 or 2011 car, and it was to test GP2 tyres, though again there has been no official statement on this. However it is now clear that the test was not conducted at Bahrain and may have been for a private client.
Ahead of the Monaco Grand Prix Pirelli called for more testing “It is quite clear that the sport has to change its ways” argued Paul Hembery. “We need to find a better way of testing, I don’t think that means going back to full test teams but there needs to be a better way or an ability to allow us sometimes to change. If you could stay on after the race with a couple of teams and rotate them each race then you are in a much better situation, that would be the dream, but I don’t think it will ever happen.”
It appears however that it has, at least to a small extent already been happening much to the annoyance of Red Bull team boss Christian Horner who told Autosport’s Jonathan Noble that “I can understand Pirelli wanting to test the tyres, as they have obviously got issues with the tyres. What is disappointing is that it has been done in a not transparent manner. A three-day test has taken place with a current car on tyres that are going to be used in the next grand prix. Irrelevant of what you call it, that is testing. I think there is confusion between what is contractually permissible and what a team is allowed to do within the sporting regulations, It is a situation that we need clarification on.”
The Mercedes W04’s sported a number of updates in Free Practice at Monaco. The front wing grew what looked liked insect like antenna in the first session, these were simply tyre monitoring devices.
The rear suspension of the car was altered on one of the cars, this was made possible by giving the transmission a new carbon fibre skin. It is not clear if this transmission was used in the race. 
Centre line cooling ducts appeared on the car at Monaco, as is common place on the current breed of cars. The track temperature exceeded 40C which presents cooling challenges for most cars.
Here we get a good look at the brake setup on the W04 used in Monaco, the car uses Brembo callipers mounted at the rear of the disc. The disc in this car features four cooling drillings across its width. Also of note is the cooling channel around the base of the disc up to the inner face of the caliper. Note the forward mounting point of the upper wishbone sitting forward of the bulkhead.
Before the race Mercedes changed the rear brake cooling drums on both cars, whilst on car 10 driven by Hamilton the steering rack and right rear brake caliper were changed, possibly to make him more confident in the car, and some parameters associated with the changes were also made.
