2010 Mclaren

Apparently Piola says in in lastest book that last year's Maclaren was particularly aero critical at the back end. It was fairly
pitch sensitive which required a very stiff suspension to main the ride height as constant as possible but made
the rear end twitchy.

Piola states that later into the 2010 season Mclaren were able to remedy this ?

So my questions are:

1) What features of on F1 car underbody make it pitch sensitive ? Does it have anything to do with stalling the airflow
in the diffuser? Why can there be flow separation under the car ? I understand that for the front and rear wings
and airplane wings in general if the angle of attackis too great the boundary layer separates from the wing ?
But how do you visualize this with the car's underbody ? For the diffuser is it simply a matter of the angle
being too great and the air flow separates ? What happens to the diffuser when the air flow does separate ?

Can the air flow separate under the stepped bottom portion of the car ? What are the flexible knife edge bibs for
at the front of the cars ?


2) What kind of solution is possible ? How does a driver get a lap time out a a very nervous car or twitchy car
due to the very rigid suspension ? Is it as simple as softening the suspension or would you have to change the
the geometry ?

Many things can go into making the underbody pitch sensitive.

Flow seperation under a car can occur due to adverse pressure gradient. This is also true (especially) for the diffuser. The diffuser raises the pressure, which creates an adverse pressure gradient, which acts to reverse the airflow.

If a car is pitch sensative the LAST thing you want to do is soften the suspension. When you do that, pitch and roll become more pronounced.

Don't they make most of their front downforce ahead of the front wheels, and the rear downforce more or less at the rear wheels?