Searching for more information on the 80 Squadron Happy Hooligan/Fortunello motif has been a very interesting study so far. I'm still struggling to find a source for more than about six images of these planes. However, I have found some interesting information. The writer of the Happy Hooligan strip was american, from Ohio not far from where I live. Happy Hooligan was particularly popular in Italy for some reason (I'm hoping to get an Italian article translated for me to learn why). A poet at the time of WW1 makes reference to it being the most popular strip in Italy.
One plane, #2140, has a picture of what at first appears to be a an old man crying with missing teeth. The pilot Michelle Alesio however is quoted as making reference to it being a drawing of the son of Happy Hooligan laughing which should bring him good luck. Happy Hooligan had no sons in the comic strip, he was a hobo and unmarried. However, the writer did want to introduce children into the strip and gave him 2 nephews and a niece who often appear crying at the end of the strip as Happy is "pinched" (arrested). Side note the hat he and his nephews/niece weare is a tin can upside down (he is a hobo after all). The kids interestingly have identical faces and often speak/act in unison. They are thought to be the inspiration for the Disney' Donald Duck nephews - Huey, Duey and Louie.
I've been looking through the Ohio State University archives at Happy Hooligan strips circa 1903. It's obvious a drawing of one of these nephews is the character on 2140. I haven't found an exact match to a strip yet, but the theme of them with their mouths wide open crying is oft repeated.
I'm waiting presently on the Italian aces book from Osprey. I know it has a page with some of this information on it.