Pittsburgh ? Has the national psyche healed enough?

It’s been more than four years since terrorists crashed Flight 93 in rural southwestern Pennsylvania, killing forty crew members and passengers. Some movie producers are hoping that American audiences are now finally ready to watch what happened on that plane.

Outside London this month, British writer-director Paul Greengrass began shooting a Flight 93 movie, produced by Universal Pictures and London-based Working Title Films. In Los Angeles, American filmmaker Peter Markle is finishing up his movie, produced by Fox Television Studios for the A&E cable network.

The films are part of a growing trend of new Sept. 11-themed movies. Oliver Stone is shooting an untitled 9/11 film; Mike Binder’s “Reign O’er Me” deals with 9-11-related grief; and a movie adaptation of the book “102 Minutes” and a TV miniseries on the 9-11 Commission’s findings are planned.

Actors Ty Olsson, as Mark Bingham, left, and Jeffrey Nordling, portraying Tom Burnett, appear in the A&E Original Movie Flight

Industry experts say it’s not surprising filmmakers would want to tell the story of that day.

“It’s probably the most dramatic story of my lifetime. It is a seminal event for people who are younger than the World War II generation,” said Delia Fine, A&E’s vice president of film, drama and music.

Paul Dergarabedian, president of the Los Angeles-based box office tracking firm Exhibitor Relations Co., said everyone was touched by the attacks so it’s a story that everyone can relate to. He said he believes that will make the films profitable.

Observers say it worked earlier this year, when the Discovery Channel attracted large audiences to its docudrama “The Flight that Fought Back.”

But that wasn’t the case immediately following the attacks, when filmmakers and studios excised the Twin Towers from trailers, posters and some movies.

“You need the years to sort of let the emotion go, to be sensitive, but to let the culture as a whole experience it fresh without it being exploitive,” said David Madden, Fox TV Studios’ executive vice president of scripted programming. “If you tried to do it in 2002, it would have been too raw, too fresh.”

Greengrass’ film is scheduled to be released in theaters April 28. The $15 million film, “Flight 93,” will have an improvised, documentary feel as it re-enacts in real time what happened on the ground and inside the fated plane.

Last year, the official 9-11 Commission report said the hijackers crashed the United Airlines aircraft as passengers tried to take control of the cockpit.