United Air Lines Flight 266
| United Air Lines Flight 266 | |
|---|---|
_(16279316443).jpg) An identical aircraft from United Air Lines |
|
| Accident summary | |
| Accident type | Loss of control after a total failure of the electrical system |
| place |
Santa Monica Bay , Pacific Ocean , 12 miles west of Los Angeles , California , United States
|
| date | 18th January 1969 |
| Fatalities | 38 |
| Survivors | 0 |
| Aircraft | |
| Aircraft type |
Boeing 727-22C
|
| operator |
United Air Lines
|
| Mark |
N7434U
|
| Departure airport |
Los Angeles International Airport , California , United States
|
| Stopover |
Stapleton International Airport , Colorado , United States
|
| Destination airport |
Milwaukee Mitchell International Airport , Wisconsin , United States
|
| Passengers | 32 |
| crew | 6th |
| Lists of aviation accidents | |
The United Air Lines Flight 266 (Flight number: UA266 , call sign: UNITED 266 ) was a domestic airliner of United Air Lines from Los Angeles to Milwaukee with a stopover in Denver . On January 18, 1969, a serious aircraft accident occurred on this flight when the instruments and electrical system of a Boeing 727-22C failed shortly after take-off and the machine with 38 occupants crashed into Santa Monica Bay . There were no survivors. Just five days earlier, a Douglas DC-8-63F of Scandinavian Airlines had also had an accident in Santa Monica Bay on Scandinavian Airlines system flight 933 .
machine
The aircraft involved in the accident was a Boeing 727-22C, which was five months old at the time of the accident. The machine was the work of Boeing on the Boeing Field in the state of Washington mounted. The machine had the serial number 19891 , it was the 631st Boeing 727 from ongoing production. The machine completed its maiden flight on September 4, 1968, before it was handed over to United Airlines on September 20, 1968 with the aircraft registration number N7434U . The three-engine medium range - narrow-body aircraft was equipped with three Turbojettriebwerken type Pratt & Whitney JT8D-7 equipped. By the time of the accident, the machine had completed a total of 1,036 operating hours.
crew
There was a crew of six on board, consisting of a flight captain, a first officer and a second officer as well as three flight attendants:
- The captain was the 49-year-old Leonard A. Leverson from Santa Ana , California , who had been hired on September 26, 1946 by United Air Lines. Leverson had type ratings for the Douglas DC-3 , DC-6 , DC-7 , DC-8 , Convair CV-340 and Boeing 727 aircraft. He had 13,665 hours of flight experience, of which he had completed 1,908 hours in the Boeing 727.
- First officer was Walter R. Schlemmer, 33, from Camarillo , California, who had worked for United Air Lines since May 4, 1964. Schlemmer had type ratings for the aircraft types Douglas DC-6, Douglas DC-7 and Boeing 727. He had 6,642 hours of flight experience as a pilot and a further 889 hours as a second officer, on board the Boeing 727 he had 1,842 hours as a pilot and 543 hours graduated as second officer.
- Second officer was Keith R. Ostrander, 29, from Newbury Park , California, who had been with United Air Lines since October 9, 1967. Ostrander was certified for Douglas DC-6 and Boeing 727 machines. His cumulative flying experience was 174 hours as a pilot and 460 hours as a first officer. On board the Boeing 727 he had only completed 40 hours with the rank of second officer.
the accident
The plane was scheduled to depart from the gate at 5:55 p.m. local time, but the take-off was delayed to 6:07 p.m. due to bad weather and charging problems. The start took place in the dark, light rain and fog. The take-off run was carried out at 6:17 p.m. from runway 24. While crossing the coastline, the pilots made a right turn with the machine until a course of 270 degrees was reached. At 18:18:30, an engine fire warning sounded in the cockpit for engine number 1. The pilots then switched it off, which also caused the generator of this engine to fail. The machine had been in operation since January 15, 1969 with a defective generator No. 3. The pilots requested a return to Los Angeles Airport. Shortly thereafter, generator No. 2 also failed, which completely lost the on-board voltage. The battery-powered emergency power system also failed. All on-board instruments were unlit in the dark and could no longer be read. There were no more radio messages and no radar data from the transponder coming from the machine. The air traffic control radar in Los Angeles indicated that the machine was entering a left turn before disappearing from the radar.
root cause
The National Transportation Safety Board (NTSB) investigated the incident. Investigators found that the most likely cause of the accident was the disorientation of the flight crew at night after a total failure of the instrument displays due to a complete power failure. The NTSB could not determine why all generator power was lost and why the emergency power system was either not activated or not working.
The machine had been in operation since January 15, 1969 with generator No. 3 out of order. This was permissible because the aircraft was considered airworthy according to the list of minimum equipment with only two operational generators, provided certain procedures are followed and the electrical loads are monitored during the flight.
The NTSB was unable to determine why all generator power had been lost. The failure of generator no. 2 was associated with the bundling of all three generator loads on this generator after engine no. 1 was switched off. When engine no. 1 was switched off, the electrical energy of the associated generator was lost, so that generator no. 2 was the only source of power generation. Under such conditions, the aircraft battery powered standby power system should provide the electrical power necessary to operate and illuminate basic flight instruments. For reasons that could not be determined, the emergency power network either failed or was not activated.
The most likely cause of the accident is a crash of the machine after spatial disorientation of the crew due to the total failure of the on-board power supply.
swell
- United Airlines Flight 266, Boeing Model 727-22C, N7434U in the Lessons Learned of the Federal Aviation Administration
- Electrical failure and crash into ocean, United Air Lines, Inc., Boeing 727-22C, N7434U, near Los Angeles, California, January 18, 1969 , National Transportation Safety Board , March 18, 1970.
- Accident report B-727, N7434U , Aviation Safety Network
Coordinates: 33 ° 56 ′ 56 ″ N , 118 ° 39 ′ 30 ″ W.