Who made warship floatplane launching a comparatively safe and routine practice?
Short answerThe Royal Navy probably fielded the practical system first through greater 1920s investment, although several navies reached similar ideas at roughly the same time.
NotesThe early American black-powder launch shows how experimental shipboard aviation could be. The Royal Navy gained a narrow practical lead by investing more heavily after the First World War and installing floatplanes on more ships. American designers could draw on information already demonstrated in British service while developing their own equipment. Several navies reached similar ideas on paper at about the same time, with Britain building the system first.