Skyjacked

Commercial airliner piloted by Charlton Heston is hijacked by someone claiming to have a bomb. Whether you consider it a knockoff of Airport or not, it's very much in the same vein as that film and its sequels. I see IMDb gives away the identity of the hijacker in their summary which is weird since the first 40 minutes of the movie is about that mystery. No spoilers here though.

Full of the stereotypical cast you might expect from an Airport movie: the pilot and stewardess who used to have a thing (Charlton Heston, Yvette Mimieux), aging stars (Walter Pidgeon, Jeanne Crain), up-and-coming youngsters (Susan Dey and future Spider-Man Nicholas Hammond), professional athlete (Rosie Greer), pregnant lady (Mariette Hartley), and a troubled soldier (James Brolin). The tension aboard the plane is pretty good but the dated flashback sequences are silly. Not bad of its type. First 45 minutes or so is best. If you like the Airport movies you'll surely like this.