Abuuri nooc ka mid ah weedhan adag Williams FW31 waa Formula One baabuur tartanka, designed iyo dhisay by WilliamsF1.
Dabcan, nooc ka mid ah jumlada ka sii adag waa "Williams FW31 waa Formula One baabuur tartanka baabuurta, kaas oo Williams u isticmaali doonaa inuu ku tartamo 2009 Formula One xilli ciyaareedka. "