Delta Air Lines Flight 723 was a Douglas DC-9 twin-engine jetliner, operating as a scheduled domestic passenger flight from Burlington, Vermont to Logan International Airport in Boston, Massachusetts, with an intermediate stop in Manchester, New Hampshire. On July 31, 1973 at 11:08 AM, while on an instrument landing system (ILS) instrument approach into Logan in low clouds and fog, the aircraft descended below the glidepath, struck a seawall and crashed, killing all 89 occupants; two people initially survived, but later died of their injuries.

Delta Air Lines, Inc., typically referred to as Delta, is one of the major airlines of the United States and a legacy carrier. One of the world's oldest airlines in operation, Delta is headquartered in Atlanta, Georgia. The airline, along with its subsidiaries and regional affiliates, including Delta Connection, operates over 5,400 flights daily and serves 325 destinations in 52 countries on six continents. Delta is a founding member of the SkyTeam airline alliance.Delta has nine hubs, with Atlanta being its largest in terms of total passengers and number of departures. It is ranked second among the world's largest airlines by number of scheduled passengers carried, revenue passenger-kilometers flown, and fleet size. It is ranked 69th on the Fortune 500. The company slogan is "Keep Climbing."