Throughout the serial aircraft change during flying sequences. A plane will be shown taking off and suddenly its now a different plane shown flying. The hero flying his plane goes to transport himself to another plane, or car, or boat, and it will become a different airplane. Sometimes the film is inverted to give the impression of the direction it's going. Usually you will notice backward numbers on the planes during this effect.
Chapters 7 & 8: Differences in ship's masts & rigging.
In Chapter 3, the phantom aircraft changes from a single seat to a dual seat aircraft after picking up Morton and the girl.
In Episode 8, the sails are furled on the smugglers' ship, but when it explodes and burns, the sails are flying and aflame.
Chapter eight: The 'Navy' sub that is blowing up the schooner has an "U" designation.
Chapter eight title card: "ALFAME IN THE SKY" Wrong! The plane blew up in flames on the ground.
Edmond says the poison gas will kill anyone breathing it within minutes. It's never explained how everyone survived the poisonous gas released in the lab.