Mobile Suit Gundam Thunderbolt: December Sky English Subbed

During the One Year War of U.C. 0079, the Earth Federation and Principality of Zeon engage in a fierce battle at the "Thunderbolt Sector", a shoal zone in the former Colony Side 4 "Moore". After successfully infiltrating Zeon's sniper field, ace Federation pilot and jazz enthusiast Io Fleming is given control of the latest Gundam prototype.

(Source: Gundam Wikia)