2. More than 50 percent of outdated aerial flares are duds. As the video I shot at the June 13 event story illustrates, many expired flares don't operate properly. That's what I observed during the live-fire exercise over the waters of King Harbor. To be clear, most (but not all) aerial flares shot into the sky, but well over half failed to ignite once airborne. This applied to aerial flares with expiration dates as recent as 2011. Coastguardsman Gina Miele, who supervised the exercise, said that Coast Guard research backs up our experience. "That's why it is important to keep your flares up to date," she said.