ココ・ソロ
In 1922, "O-16" was stationed at Coco Solo, Panama Canal Zone, for diving tests and maneuvers. She cruised in formation with , , , and submarine tender to Guantanamo Bay, Cuba, on 26 January, and continued maneuvers in and around the Virgin Islands. In April, she returned to Coco Solo, where electricians and engineers put her in prime condition.