Ginga Tetsudou 999

Synopsis

The planet, the Knights of Kilimanjaro. Chivalry lives on here and two countries are fighting a proper, open war. There, Tetsuro witnesses a biplane dogfight. He spots one pilot who is slacking off during the dogfight. The name of this pilot is Izaka. He's not of high lineage like the other pilots and wants nothing more than to fly the skies like a bird. But, his dear friend Kikuo is killed from another plane's attack. Izaka explodes in rage while he watches everyone celebrating the ceasefire, ignoring the fact that his friend was sacrifices.

(Source: Crunchyroll)