Continuity mistake: The small plane's pilot identifies the aircraft as 232Z. But in the exterior shots, the aircraft's identification is N9750Y. (00:35:00)
Other mistake: As the rescue copter is lowering down the pilot, it can be seen flying above and in front of the jet so he can enter into the hole above the copilot seat, but passengers looking out of the side windows of the plane can see the copter and that the first guy fails? Not possible.
Answer: It's all about branding and marketing. The first Airport film was hugely successful, prompting a sequel. Reusing "Airport" in the title has built-in name recognition that people would immediately associate with the previous film, which helps sell tickets. The movie is part of what became a movie series (four in all) under the collective "Airport" name.
raywest ★