Williams FW31

Williams FW31

Kazuki Nakajima driving the FW31 at the 2009 Spanish Grand Prix
Category	Formula One
Constructor	Williams
Designer(s)	Sam Michael (Technical Director) Ed Wood (Chief Designer) Jon Tomlinson (Chief Aerodynamicist)
Predecessor	Williams FW30
Successor	Williams FW32
Technical specifications[1]
Chassis	Carbon-aramid and honeycomb composite monocoque.
Suspension (front)	Carbon fibre double wishbone, with pushrod activated springs. Zero keel geometry.
Suspension (rear)	Double wishbone, with pushrod activated springs.
Wheelbase	3,100 mm (122.0 in)
Engine	Toyota RVX-09 2.4 L (146 cu in) 90° V8. Limited to 18,000 rpm. naturally-aspirated, longitudinally mid-mounted.
Transmission	Williams 7-speed electro-hydraulically actuated, semi-automatic, seamless shift.
Power	740 hp @ 18,000 rpm[2]
Weight	605 kg (1,334 lb) (including driver)
Fuel	Esso
Lubricants	Mobil 1
Tyres	Bridgestone Potenza
Competition history
Notable entrants	AT&T Williams
Notable drivers	16. Nico Rosberg 17. Kazuki Nakajima
Debut	2009 Australian Grand Prix
Last event	2009 Abu Dhabi Grand Prix
Races Wins Podiums Poles F/Laps 17 0 0 0 1

The Williams FW31 was a Formula One motor racing car, designed and built by Williams F1. The AT&T Williams team used the FW31 to compete in the 2009 Formula One season. The car was unveiled on 19 January 2009 at the Autódromo Internacional do Algarve circuit in southern Portugal, and was first driven by the team's test driver Nico Hülkenberg. It was a mid-field runner, in contention for points on many occasions when driven by Rosberg, but rarely contending for podiums. Rosberg could have finished in third position at Marina Bay during the 2009 Singapore Grand Prix if he had not run wide on the exit of the pit lane and received a penalty.

Rosberg was criticised for failing to achieve a pole position while topping the times in practices on numerous occasions, notably at the 2009 Brazilian Grand Prix - the Williams cars had excelled during practice sessions in wet conditions, but did not produce the same level of performance in qualifying. While Rosberg often scored points, and elevated the car to a finishing position that it was considered incapable of, Nakajima failed to score a point all season and possibly cost the team a higher position in the championship standings than the seventh place they eventually achieved.

The Williams FW31 was the first British F1 car to use Esso-branded fuel since 1973, as well as the first Williams F1 car to use Mobil 1 lubricants since 1988 season, as they had been using ExxonMobil brands since 1999.