On February 13, 1997, about 1217 eastern standard time, the aft cargo door of a Boeing 727-232, N416DA, opened during takeoff from The William B. Hartsfield-Atlanta International Airport, Atlanta, Georgia. The airplane, Flight 1180, was operated by Delta Air Lines as a scheduled, domestic, passenger flight under the provisions of Title 14 CFR Part 121, and instrument flight rules. Instrument meteorological conditions prevailed. An instrument flight plan was activated. There were no injuries to the airplane's occupants, and the airplane had minor damage. The flight, which was originating at the time of the incident, was destined for Charleston, South Carolina. The captain of Flight 1180 stated that the pushback and taxi were "normal with all lights extinguished." He noted, "during takeoff roll, the aft cargo light on the second officer's panel illuminated, cabin pressurization was normal." When the airplane reached approximately 900 feet, there was a "pop", and the airplane lost pressurization. A passenger noticed the cargo door had opened and brought it to the attention of a flight attendant. According to the pilot, the #3 engine then experienced difficulties. There was a "decrease in EPR, N1, and N2 and the engine failed." The airplane returned to Atlanta for an uneventful landing. According to Delta's Operating Manual for the Boeing 727, the cargo light is on the Second Officer's panel and checklist. During the Captain's pre-flight checklist, he inquires as to whether the Second Officer completed his checklist. The Captain and First Officer do not visually check the Second Officer's panel for illuminated lights. According to Delta's records, the Second Officer had 1216 hours of total flight time in the 727, and 179 hours in the last 90 days. The Second Officer was originally hired in October 1991, furloughed in October 1993, and recalled in June 1996. He had 372 hours in the 727 since he was recalled. It was later noted that one bag fell out of the baggage hold onto the runway. Subsequent examination of the airplane did not reveal any structural damage to the airframe. The same cargo door was removed for minor repairs, and was re-installed on the airplane. The latching mechanism was examined and was found capable of smooth operation. There was no damage to the door's locking hooks. An electrical continuity check of the door warning circuitry was positive, and the bulb in the cockpit warning light would illuminate. According to Delta, all of the ground personnel interviewed stated they did not lock the cargo door. They were unable to determine who last operated the cargo door.