Toaru Hikuushi e no Koiuta

Synopsis

An initial invading force by the Sky Clan is easily destroyed by the Isla defense group, so Admiral Melze orders all planes to commence a full scale bombing attack of the enemy's headquarters while at the same time they all marvel at the beauty of the Holy Spring. The students are sent on their first mission to provide recon of the area, but as they are about to go, Claire and Ignacio are pulled out of the group by Claire's countess, who warns her and his life are too important to lose. Furthermore, Ignacio will be appointed as her bodyguard. The attacking Isla planes easily destroy the inferior Sky Clan planes and pursue, but Chiharu and Mitsuo soon spot another carrier force which appear to be way more powerful than the ones that the Isla planes are attacking. They are able to relay the information back to HQ, who realize that the fleet they are attacking is a decoy. The rest of the students learn about Chiharu and Mitsuo still monitoring the enemy fleet. Feeling emboldened, Chiharu and Mitsuo continue to provide recon for the attacking Isla planes on the new enemy fleet and bombers. However, Mitsuo is shot by an enemy plane and badly wounded, and orders Chiharu to escape by parachute before he commandeers the plane away from her, to his death. The training pilots hear over the radio that the Isla attacking planes have walked into an ambush and that more enemy planes are now preparing to bombard Isla, and prepare to defend the island on their own.

(Source: Wikipedia)