United Airlines Flight 553 United Airlines Flight 553 was a scheduled flight from Washington National Airport to Omaha, Nebraska, via Chicago Midway International Airport. On December 8, 1972, the Boeing 737-222 serving the flight, City of Lincoln, registration crashed during an aborted landing and go around while approaching Chicago Midway International Airport. The plane crashed into a residential neighborhood, destroying five houses; there was an intense ground fire. 43 of the 61 aboard the aircraft and two on the ground Among the passengers killed were Illinois congressman George W. Collins and Dorothy Hunt, the wife of Watergate conspirator E. Howard Hunt. This crash was the first fatal accident involving a Boeing 737, which had entered airline service nearly five years earlier in February 1968. Flight United Airlines Flight 553 was a scheduled service from Washington National Airport to Omaha, Nebraska, via Chicago Midway International Airport. used for the flight was a four-year-old Boeing 737-222 City of Lincoln, registration (built in 1968). The flight-deck crew consisted of Captain Wendell Lewis Whitehouse (age 44), First Officer Walter O. Coble (43), and Second Officer a highly experienced pilot with approximately to his credit, had been with the airline since 1956 and had logged more than on the Boeing 737 cockpit. First Officer Coble had more than 10,600 flight hours (including nearly 1,700 hours on the Boeing 737) under his belt and Second Officer Elder had close to 2,700 hours, with nearly 1,200 of them on the Boeing 737. Accident The accident occurred as the aircraft was on a northwesterly heading to land on runway 31L at Midway Airport. The area was overcast at the time: a pilot landing on that runway immediately after the accident later reported that the airport was only visible below Flight 553 was on instruments, cleared by air traffic control at 14:24 CST for a nonprecision approach. The localizer approach for runway 31L used an Outer Marker Beacon (OMB) named "Kedzie", located prior to the runway threshold. Under the published landing procedures, the aircraft was to maintain a minimum altitude of until it passed the OMB, at which point the flight was allowed to descend to a minimum descent altitude (MDA) of Published procedures, and pilots operating under instrument flight rules, use mean sea level (MSL) as the point of reference for measuring altitude; at Midway Airport, an altitude of corresponded to an actual height above ground level (AGL) of only When Flight 553 reached the Kedzie OMB, the aircraft was still at an altitude of MSL, a full above the minimum crossing altitude of MSL, above the height at which the decision on whether to land must be finalized. Realizing the aircraft was too high, the captain extended the spoilers (speed brakes) and steepened the aircraft's descent rate to per minute (in comparison with the per minute approximate rate specified by United Airlines for the final segment of a nonprecision approach; typical precision approach descent rates are per minute). The aircraft continued to descend at a rate of per minute, emerging from cloud above the ground, until it reached its level-off altitude at MDA. The captain leveled the plane off and increased engine power, but did not advance the throttles fully. With the spoilers still extended, thrust was not enough to maintain level flight without losing speed. The stick shaker, a stall warning device attached to the pilots' control yoke, activated 6–7 seconds after the aircraft leveled off and continued to sound as the aircraft entered an aerodynamic stall. The aircraft struck trees and then roofs along W. 71st Street before crashing into a house at 3722 W.