In a documentation that was published in the magazine "The Spanish and American illustration" (Year XXX, number XVII, published in Madrid, May 8, 1886), appears the patent for an airship gas engine.

-Engineer and inventor R. Fradera from Barcelona received the patent for his Aircraft with a special gas engine.

-The project existed but there is no information about any application.

-From this magazine we have extracted three views from the patent in which we see the engine inside the airship body, along the longitudinal axis, placed and protected in a sort of chimney.

-In the first figure we can see the mechanical transmission for the propeller.

-In the second one, the engine installation, and in the third one the engine itself.

-It seems that the gas that was used, is the hydrogen of the envelope, or city gas if that was used for said mission.

“Drawing included in the patent”
(courtesy of Alvaro G. Cascón)