Hop Harrigan was an aviation strip begun in the first issue of All-American comics by Jon L Blummer (Jon Elby).  Hop was a teenager taught to fly by his mentor, "Prop" Wash.  His friend, Ikky, was  his mechanic.  The first new cast member was Gerry, a spoiled little rich girl whose parents paid Hop to give flying lessons.  Mostly to keep her out of their hair.
From All -American 8, Hop, Gerry, Ikky and Prop.

The next character to join the strip was Miss Snap, housekeeper and treasurer of the All-American Aviation Company.


from All-American 15.

In November 1941, Ikky's name was changed to Tank Tinker, possibly due to the fact that Captain Midnight's sidekick was also called Ikky.  Hop Harrigan got his own radio program in 1942, and the sponsors probably wanted to avoid confusion. The radio program also changed Gerry's name to Gail Nolan.  The radio show lasted until February 1948.

 

The last major cast member to be introduced was Hippity, a silent boy, found on one of Hop's oriental adventures, in April 1943, All-American 49.


All-American 69 Hop, Tank, Hippity and Miss Snap

Hop ran on the radio up to 1947 and also appeared in a movie serial (3/28/46).  Pretty good for somebody who never had his own comics, and was rarely even cover featured!