Williams making car changes to ensure legality

Its unconventional wing mirrors and part of the suspension were among the standout features when the Williams FW42 finally arrived at Barcelona for pre-season testing.

However, Motorsport.com understands the FIA was not happy with elements of these designs and Williams will modify them to ensure it does not encounter a problem in Australia.

The FIA technical regulations state that only six suspension members are permitted: four wishbone members, one pushrod and one steering arm.

Williams FW42 low wishbone

Photo by: Giorgio Piola

As the above Giorgio Piola drawing shows, Williams introduced a thin, seventh member that runs along the edge of the lower wishbone.

This will be removed from the suspension for the first race.

Meanwhile, the curved Williams wing mirrors that appeared in both pre-season tests will change to a new version that the team has not run before.

However, the upper wishbone mounting point – illustrated by the drawing below – has been cleared for use.

Williams FW42 suspension detail

Photo by: Giorgio Piola

The need for Williams to abort its attempted 2019 innovations comes at the same time its chief technical officer Paddy Lowe has taken a "leave of absence" for "personal reasons".

It also follows two weeks of pre-season testing that Williams missed the start of, and led to unfavourable comments from its drivers George Russell and Robert Kubica about the team's pace and preparation respectively.