Universal Pictures’ “United 93” has been tapped to open the Tribeca Film Festival on April 25.

Paul Greengrass-helmed pic follows the saga of the hijacked United Airlines flight that crashed outside of Shanksville, Penn., on Sept. 11, 2001.

Tribeca brass said Wednesday that family members who lost loved ones aboard the flight, as well as members of 9/11-related orgs, will be on hand for the pic’s preem, along with the filmmakers.

The film re-creates the doomed flight’s story in real time.

“The events of 9/11 had a massive effect on me, like everyone, and I wanted to use my position as a filmmaker to contribute something so they are not casually forgotten,” said Greengrass, whose credits include “Bloody Sunday” and “The Bourne Supremacy.”

Tribeca fest was founded by Jane Rosenthal, Craig Hatkoff and Robert De Niro to help rebuild Lower Manhattan in the wake of the 9/11 attacks.

“As we enter our fifth festival, we are honored to showcase a film that portrays a story of bravery and sacrifice of the men and women who dedicated their lives that day,” Rosenthal said.

“United” — formerly known as “Flight 93” — was produced by Working Title’s Tim Bevan and Eric Fellner, along with Lloyd Levin and Greengrass.

U will open the pic April 28. Tribeca runs April 25-May 7.