North American Surveillance Systems introduced a sliding, air-operable cargo door for the Cessna Caravan. According to the Deland, Fla.-based company, the enhanced door requires no modification to the aircraft and installs in place of the standard two-piece cargo door. Installation of the new door, which adds about 45 pounds but has the same exterior profile as the original, takes about one hour, the company said. The air-operable feature enables parachute and bundle-dropping operations, it noted.