The registration of Ali Khali's biplane is APF1, an in-joke referring to Gerry Anderson and Sylvia Anderson's production company, AP Films.
This episode was the 36th episode produced and the 23rd broadcast.
Commander Shore and Lieutenant Fisher's dialogue states that it takes a Supersonic 101 jet airliner one minute to go 20 miles, stating that the plane's top speed is in excess of 1,200 mph.
X2-Zero reveals that El Hudat has been in prison for the past year.
Ali Khali's nefarious brother El Hudat had previously appeared in the episode Star of the East (1965).