Idol Bouei-tai Hummingbird

Both are mid-90s series about a group of girls (presumably sisters) who pioneer their way through new fields in society to reach the top and achieve their dreams. Cute side characters are sprinkled throughout along with a decent dose of silly and serious moments. Catchy J-pop songs, group dynamics about how to work as a team, discovering hidden secrets about the dark side of their work, and the influence of an outsider are prominent features in both series. They also have similar animation styles and character designs. 

Musicians who have an oddly strong influence on the world, and are strangely tied up in jet aircraft dogfighting one way or another. Plus cute girls and great 90s-era aesthetics! 

Idols and war machines. 

Both have cute girls flying airplanes and are both from the early '90s.