It's difficult to think of any connection between this film and "Murder on the Orient Express" (1974), but I consistently question Michael York’s career trajectory. He possesses a certain delicate attractiveness, yet his performance feels almost as stiff as the airship itself. His role is that of a soldier descended from a prominent German family (Richter). Both Germany and Britain are vying for his cooperation – predictable, really. After joining forces with Bosch, he's placed on this remarkable airship, built to achieve impressive altitudes and velocities, tasked with sabotaging what remains of the British war effort. Will he be able to stop their scheme given how much stronger they are? Unfortunately, there’s absolutely no sense of danger throughout. The film waits nearly 40 minutes before we even glimpse the airship, and by then it's far too little, arriving far too late. The supporting cast is acceptable; Anton Diffring and Marius Goring, though underutilized, fulfill their roles adequately. However, the story moves slowly, with an excess of dialogue and a severe lack of action sequences. Maybe we would have developed explosive ammunition sooner if the production team had taken inspiration from this film instead.

Source on TMDB