Director Paul Greengrass has started principal photography on his9/11 feature film Flight 93 for Universal Pictures and Working Title Films in associationwith Sidney Kimmel Entertainment.

Greengrass (Bloody Sunday, The Bourne Supremacy) started shooting Flight 93 at the UK's Pinewood Studios on November14, and shooting will continue on location in the UK and the US.

The film will re-enact United Airlines 93, the last of the fouraircraft hijacked on September 11, 2001. The production has the support of familymembers of flight 93's victims. The story, told in real time, will followevents on the plane as well as on the ground with air traffic controllers andmilitary command centers.

"9/11 was unique - the mostimportant event of our lifetime, casting a shadow over all our futures."Greengrass said. "It's vital for cinema to begin the task of exploring what itmeant, and what it continues to mean today. Hopefully Flight 93 will be a worthy contribution to that process."

Tim Bevan, Eric Fellner and Lloyd Levin are producing. Universalis planning a US release for April 28, 2006 with other territories to follow.

A websitedevoted to the film will launch on Wednesday with information on theproduction, a memorial to the victims and a forum for users.