Pan Am Flight 214 was a scheduled flight of Pan American World Airways from San Juan, Puerto Rico, to Baltimore, Maryland, and Philadelphia, Pennsylvania. On December 8, 1963, the Boeing 707 serving the flight crashed near Elkton, Maryland, while flying from Baltimore to Philadelphia, after being hit by lightning. All 81 occupants of the plane were killed. The crash was Pan Am's first fatal accident with the 707, which it had introduced to its fleet five years earlier. An investigation by the Civil Aeronautics Board concluded that the cause of the crash was a lightning strike that had ignited fuel vapors in one of the aircraft's fuel tanks, causing an explosion that destroyed one of the wings. The exact manner of ignition was never determined, but the investigation yielded information about how lightning can damage aircraft, leading to new safety regulations. The crash also spawned research into the safety of various types of aviation fuel and into methods of reducing dangerous fuel-tank vapors. Pan American Flight 214 was a regularly scheduled flight from Isla Verde International Airport in San Juan, Puerto Rico, to Philadelphia International Airport with a scheduled stopover at Baltimore's Friendship Airport. It operated three times a week as the counterpart to Flight 213, which flew from Philadelphia to San Juan via Baltimore earlier the same day. Flight 214 left San Juan at 4:10 p.m. Eastern time with 140 passengers and eight crew members, and arrived in Baltimore at 7:10 p.m. The crew did not report any maintenance issues or problems during the flight. After 67 passengers disembarked in Baltimore, the aircraft departed at 8:24 p.m. with its remaining 73 passengers for the final leg to Philadelphia International Airport. As the flight approached Philadelphia, the pilots established contact with air traffic control near Philadelphia at 8:42 p.m. The controller informed the pilots that the airport was experiencing a line of thunderstorms in the vicinity, accompanied by strong winds and turbulence. The controller asked whether the pilots wanted to proceed directly to the airport or to enter a holding pattern to wait for the storm to pass. The crew elected to remain at 5,000 feet in a holding pattern with five other aircraft. The controller told the pilots that the delay would last approximately 30 minutes. There was heavy rain in the holding area, with frequent lightning and gusts of wind up to 50 miles per hour (80 km/h). At 8:58 p.m., the aircraft exploded. The pilots were able to transmit a final message: "MAYDAY MAYDAY MAYDAY. Clipper 214 out of control. Here we go." Seconds later, the first officer of National Airlines Flight 16, holding 1,000 feet higher in the same holding pattern, radioed, "Clipper 214 is going down in flames." The aircraft crashed at 8:59 p.m. in a corn field east of Elkton, Maryland, near the Delaware Turnpike, setting the rain-soaked field on fire. The aircraft was completely destroyed, and all of the occupants were killed. The aircraft was the first Pan American jet to crash in the five years since the company had introduced their jet fleet. A Maryland state trooper who had been patrolling on Route 213 radioed an alert as he drove toward the crash site, east of Elkton near the state line. The trooper was first to arrive at the crash site and later stated that "It wasn’t a large fire. It was several smaller fires. A fuselage with about 8 or 10 window frames was about the only large recognizable piece I could see when I pulled up. It was just a debris field. It didn’t resemble an airplane. The engines were buried in the ground 10- to 15-feet from the force of the impact." It was soon obvious to firefighters and police officers that little could be done other than to extinguish the fires and to begin collecting bodies. The wreckage was engulfed in intense fires that burned for more than four hours. First responders and police from across the county, along with men from the United States Naval Trainin