United Airlines Flight 553

United Airlines Flight 553

A United Airlines Boeing 737-222 similar to the aircraft involved in the accident.
Accident summary
Date	December 8, 1972
Summary	Pilot error
Site	Chicago, Illinois, United States
Passengers	55
Crew	6
Fatalities	45 (including 2 on ground)
Injuries (non-fatal)	16
Survivors	18
Aircraft type	Boeing 737-222
Operator	United Airlines
Registration	N9031U
Flight origin	Washington National Airport
Stopover	Chicago Midway Int'l Airport
Destination	Eppley Airfield

United Airlines Flight 553 was a Boeing 737-222 that crashed during an aborted landing and go around while approaching Chicago Midway International Airport on December 8, 1972. The plane crashed into a residential neighborhood, destroying five houses. 43 of the 55 people aboard the aircraft, and two others on the ground, were killed.

Among the passengers killed were Illinois Congressman George W. Collins and Dorothy Hunt, the wife of Watergate conspirator E. Howard Hunt. Also killed were Michele Clark, a correspondent for CBS News and one of the first female African-American network correspondents, and Alex E. Krill, an ophthalmologist from the University of Chicago.

This crash was the first fatal accident involving a Boeing 737, which entered airline service in February 1968.

United Airlines Flight 553 was a scheduled service from Washington National Airport to Omaha, Nebraska, via Chicago Midway International Airport. On December 8, 1972, the aircraft used for the flight was Boeing 737-222 City of Lincoln, registration N9031U.

The flight-deck crew consisted of Captain Wendell Lewis Whitehouse (44), First Officer Walter Coble (43) and Second Officer Barry Elder (31). The captain, a highly experienced pilot with approximately 18,000 flight hours to his credit, had been with the airline since 1956 and had logged 2,435 hours in the Boeing 737 cockpit. First Officer Coble had more than 10,600 flight hours under his belt and Second Officer Elder had close to 2,700 hours.

The accident occurred as the airplane was making its final approach to Midway Airport.

At 14:24 Central Standard Time, Flight 553 was cleared by air traffic control to Midway Airport on an approach to runway 31L. The localizer approach for runway 31L used an Outer Marker Beacon (OMB) named "Kedzie," located 3.3 nmi (6.1 km; 3.8 mi) prior to the threshold of runway 31L. Under the published landing procedures, the aircraft was to maintain a minimum altitude of 1,500 feet (460 m) until it passed the OMB, at which point the flight was allowed to descend to a minimum altitude of 1,040 feet (320 m). Published procedures, and pilots operating under instrument flight rules, use mean sea level (MSL) to measure altitude; at Midway Airport, an altitude of 1,040 feet (320 m) MSL corresponded to an actual height above ground level (AGL) of only 429 feet (131 m). The area was overcast at the time Flight 553 landed, and pilots landing at Midway Airport immediately before Flight 553 reported that the airport was only visible below 500–600 feet (150–180 m) AGL.