Kantai Collection character personifying the USS Helena, hull number CL-50, the ninth and last of the US Navy's Brooklyn-class light cruisers as well as the second and last of the St. Louis-subclass (which had an improved design over the other Brooklyns). She is named after the relatively obscure city of Helena, Montana. She is AceA4's first shipgirl who is neither Japanese nor a kaiboukan.
Visually, Helena has long brown hair with blunt bangs and yellowish green eyes. She wears a military uniform which includes a neck ribbon in the design of the American flag with a star pin, a black skirt with slits, a breastplate/corset, grey thighhighs with alternateing gray and white side stripes, and rudder footwear. Her machinery includes her 15 6-inch/47-caliber Mark 16 guns, six on each of her sides and three on top of her weapon, a modified Browning Auto 5 rifle. She has a remodeled form where her machinery is repainted darker gray, her neck ribbon is changed to a mostly yellow one, and the non-white stripes on her thighhighs are given more assorted colors. Her first remodel also gives her a significantly different light/medium damage CG showing her having larger breaks to her machinery and exposing more of her skin in the process; her damage CG while in base form is identical to her normal CG other than the visible holes, tears, and other signs of damage.