Private Fifth Class Arnold "Arnie" Gumble was a member of the Flying Hellfish, Grampa's unit in World War II. He is the father of Barney Gumble. He was in charge of watching his unit's backs inside a tank. Along with the rest of the unit, he took part in a tontine where the last surviving member would take sole possession of a group of paintings they liberated. He was one of five members of the group to die in a parade float accident in 1979. Apparently, Arnie desired to buy his way into high class society when he took part in the tontine. He had the same voice, and bad burping habits as his son, except he burps without drinking beer.
- Episode – "Mr. Plow" (mentioned only)
- Episode – "Raging Abe Simpson and His Grumbling Grandson in "The Curse of the Flying Hellfish""
- Episode – "Walking Big & Tall" (flashback)
| Flying Hellfish Members
|Abraham Simpson | Sheldon Skinner | Arnie Gumble | Asa Phelps | Iggy Wiggum | Milton Haas | Etch Westgrin | Griff McDonald | Charles Montgomery Burns | Commander Flanders|