McLaren brought a few aerodynamic improvements in China, notably their interpretation of T-wing and long longitudinal slots on the sides of the floor while on the third free practice they tried the new rear wing that didn’t choose to use in qualifying and race.
Despite major problems with the Honda engine which is more than 100 horsepower behind Mercedes and Ferrari and approximately on the level of late spec of their 2016 engine, McLaren continues to do what is in their power to improve the competitiveness of their package.
The car now has a double T-wing that is slightly different than other teams’ solutions and a longitudinal slots along the side of floor that helps isolate the airflow under the car to allow floor to work more efficiently.
We have already seen a number of interesting solutions like floor cut-outs (Red Bull and Ferrari) and more common multiple slits in front of the rear wheels which are used to reduce the effect of ‘tyre squirt’ (rotating rear wheel turbulence affecting the diffuser).
But McLaren is in this area went a step further and on each side of the floor cut a long slit that extends almost from the beginning of the floor in length of about one meter. The slot is not quite simple and vertical – it is open on the inside to allow the airflow near the sidepods to pass through the slits and seal the floor sides.
Slot allows mixing of air that travels from the top of the floor with the airflow underneath it which helps create vortices that help to seal the floor from the turbulence and help increasing aerodynamic efficiency.
In front of the slot, at the beginning of floor on each side, there are two wide longitudinal axe-like blades that create strong vortices and sent them along the edge of the floor, but McLaren already used them in Australia. On testing we saw only one blade on each side of the floor.
McLaren didn’t use new rear wing in qualifying, but ‘other upgrades work’
McLaren tested a new rear wingin third practice, but still have not chosen to use it in qualifying because it takes more changes to make it work properly.
“We used it on both cars in third practice, but as we have some small problems that we have to fix it, we decided not to use it in the race,” said Eric Boullier.
“But we will re-use it in Bahrain.”
“Other upgrades work well.”
Alonso and Vandoorne will start Chinese GP from 13th and 16th places after team expected to be less competitive than in Australia because long straights of Shanghai International Circuit.