Los ángeles del infierno

Stunt pilots refused to perform an aerial sequence that director Howard Hughes wanted. Hughes, a noted aviator himself, did his own flying. He got the shot, but he also crashed the plane.

At the start of the film in the German beer garden: A customer and a waitress indicate with their hands the number four by holding up four fingers, but in Germany the thumb is used as the first digit so they should really have used the thumb and three fingers.

The UCLA Film and Television Archive restored the film to its premiere version, which is the version currently available on DVD. In addition to reinstating the 8-minute two-strip Technicolor sequence, tinting and toning was restored to the duel at sunrise, the Zeppelin battle, the night patrol, and Monte and Roy departing for their bombing run. Note that these sequences were intact on earlier prints, but without color or special processing. The film's Intermission title card, along with Entr'acte music and exit music were reinstated as well.

Edited into La hermana blanca (1933)