In Porco Rosso, what is the model of Porco's seaplane?

In Porco Rosso, Porco’s seaplane is called the Savoia S.21.

The red aircraft is the signature visual of Hayao Miyazaki’s 1992 aviation adventure. Porco Rosso, formerly the Italian pilot Marco Pagot, uses it while working as a freelance bounty hunter against air pirates in the Adriatic. After the American pilot Donald Curtis shoots him down, Porco takes the damaged aircraft to Milan, where Piccolo’s workshop rebuilds it with help from the young engineer Fio.

There is an important aviation detail behind the answer. The aircraft in the film is fictional, even though its name resembles a real Italian SIAI S.21. Its design is especially associated with the Macchi M.33, a real racing flying boat, so the animated plane should not be treated as an exact historical reproduction of the named aircraft. The film’s in-story designation, however, is Savoia S.21, making that the canonical quiz answer.

The plane’s red color connects directly to Porco’s nickname, which means “Red Pig.” The film combines real interwar aviation references, Schneider Trophy-style racing aircraft, and fantasy, creating one of animation’s most recognizable fictional seaplanes.