Why Williams broke curfew at the F1 Austrian Grand Prix

The Williams Formula 1 team used one of its curfew jokers on Thursday evening in Austria in order to fit updated Mercedes power unit elements to both of its cars.

Mercedes has produced an update to the energy store main enclosure after recent reliability problems and made them available to all its teams.

Given the late arrival of the new items in Austria, Williams opted not to rush the job of fitting them and instead used the second of its five permitted curfew exceptions.

The ESME has been something of an Achilles Heel for Mercedes this year, and McLaren had to play a joker on Friday evening in Monaco when exploring issues in the same area after Lando Norris stopped on track in FP2.

“We have new ESME packs, which I think Mercedes are pretty open about,” said Vowles when asked about the curfew.

“We wanted to take that, but it only really appeared at 3pm on Thursday, and we had a tremendous amount of work to do. So I wanted to make sure the cars are properly prepared.”

Cadillac also played a curfew joker on Thursday evening as the team had a raft of new aero items to fit to its two cars.

Vowles also expanded on why Albon has switched to a different FW48 chassis for this weekend, the Thai/British driver having had doubts about the original’s handling properties in recent races.

“There's nothing wrong with the original chassis, but what we wanted to do after Barcelona is specifically capture that and do a series of tests back at the factory,” said Vowles.

“As a result of that, basically changing chassis is one of the easiest ways of doing it from an operational perspective. It's also something that we're used to doing for a number of reasons as you move forward.

“A long time ago there were ‘ghosts’ in chassis. I don't think I've heard that for a long, long time. The amount of force we put through it as a double-decker bus on top of it, so I assure you they don't move anymore.”

Vowles revealed that the rig testing of the previous chassis helped to produce set-up improvements for this weekend.

“In terms of what Alex is talking about, what we have seen several times this year is the balance isn't where we need it to be, and slightly differs between left and right corners,” he said.

“That's the main thing he's complaining about. It isn't a large difference, but it is enough that when you're really finely balanced and trying to get the most out of the tyres in a 50-something degree track, it gets exposed more than you would do at other circuits, and that's part of the reason for making sure we did rig work back at the factory.

“The good news is that was very positive and developed, and we made some changes here, just in small details and setting up. So I think that's an item of the past.”