Early on in the film, a V-1 flying bomb - marked 'M23' on the tail fin - takes off, veers to the right and crashes. A few scenes later, Hanna Reitsch is seen in another flying bomb, which, in its first shot from distance on the ramp, is marked... 'M23'. This was obviously spotted, because in the next scene, a close up of the tail fin, it has now magically and clumsily been changed to 'M28'.