LOS ANGELES - Barry Livingston admits he's not movie hero material. The former child star from "My Three Sons" definitely doesn't look the part.

Livingston usually gets mild-mannered, science-geek roles, so he was excited to land a role in the action movie "Final Approach," airing at 8 p.m. tomorrow on the Hallmark Channel.

The 54-year-old actor plays an airline passenger whose expertise as an aeronautical engineer allows him to help Dean Cain's character as they attempt to foil hijackers.

"I ultimately get to step up and be a hero in my own right," Livingston says. "When I got to that part in the script, I said, 'Wow, I've never done that before! How can I pass this up?' " *