**** Federal Aviation Administration Office of Accident Investigation **** **** 12/29/97 Preliminary Accident/Incident Data Record RECORD 1 **** A. Type: Accident Mid Air:N Missing:N Entry date: 12/29/97 From: SAN FRANCISCO, CA, CMO B. Reg.No.: 4723U M/M: B747 Desc: SUPER JET 747 Activity: Business Phase: Unknown GA-A/C: Air Carrier Descr: UNITED AIRLINES ACFT ENCOUNTERED SEVERE TURBULENCE AFTER TAKING OFF FROM NARITA, JAPAN, 1 PASSENGER SUFFERED FATAL INJURIES, 3 FLIGHT ATTENDANTS SUFFERED SERIOUS INJURIES, AND 94 PASSENGERS AND CREW SUFFERED MINOR INJURIES, THE ACFT RETURNED TO NARITA, JAPAN. WX: UNKN Damage: Minor C2. Injury Data: # Crew: 23 Fat: 0 Ser: 3 Min: 10 Unk:Y # Pass: 346 Fat: 1 Ser: 0 Min: 84 Unk:Y # Grnd: Fat: 0 Ser: 0 Min: 0 UNK: D. Location City: NARITA, JAPAN State: OF E. Occ Date: 12/28/97 Time: 15:10 F. Invest Coverage. IIC: Reg/DO: DO CTY: DO State: Others: JAPANESE OFFICIALS G. Flt Handling. Dep Pt: NARITA, JAPAN Dep Date: 12/28/97 Time: Dest: HONOLULU, HI Last Radio Cont: UNKN Flt Plan: IFR Last Clearance: UNKN WX Briefing: Y Other: AAI IIC: ================================================================ Aircraft Communications Addressing and Reporting System (ACARS) Aircraft Reports (AIREPs) During United Airlines Flight 826: IDENT.....LAT......LON.......TIME....ALT.....TEMP....WIND UAL826 3350N 15000E 1300 F310 MS40 270/130 = UAL826 3200N 16000E 1352 F330 MS44 290/110 = UAL826 3350N 15000E 1557 F350 MS48 275/155 = ================================================================ PRESS ADVISORY Aircraft Accident Investigation United Airlines flight 826, Pacific Ocean December 28, 1997 WASHINGTON, D.C., December 30, 1997 - The National Transportation Safety Board is investigating an accident occurring over the Pacific Ocean on December 28 involving United Airlines flight 826, a Boeing 747-100 on route from Tokyo to Honolulu. The aircraft apparently encountered turbulence, resulting in one passenger fatality and scores of injuries. The aircraft' digital flight data recorder (DFDR) arrived at NTSB headquarters at approximately midnight Monday, December 29. The DFDR records 17 flight characteristics, or "parameters." Safety Board engineers have been downloading the data since that time and report the following preliminary information. About 1 hour and 31 minutes into the flight, while cruising at 31,000 feet (not 33,000 feet as initially reported to authorities), wings level at a heading of approximately 103 degrees, the aircraft sustained a 1.8G upward load, with a 0.1G lateral (sideways) load. This upward load would have the effect of pushing an occupant down into the seat. Simultaneously, a 15 knot wind shear increased the air speed of the plane from 335 knots to 350 knots. Six seconds later, the aircraft sustained a -0.8G load. This would have the effect of pulling an occupant out of the seat, or against a seat belt if the occupant were restrained. The G forces were less than "0.0" for approximately one half of a second. During this period, the aircraft rolled to 17 degrees right wing down. The data indicate that altitude excursions up or down during the incident were less than 100 feet. Pilot control column position does not appear to have been a factor in either the positive or negative G excursions. The aircraft turned around about 23 minutes after the incident, landing in Tokyo about 2 ½ hours later. The Board's investigation will continue, including a more detailed review of the DFDR; interviews with the flight crew, cabin crew and passengers; documentation of the damage to the aircraft; weather; and analysis of air traffic control communications. The Board does not expect to issue any updates on this accident for several weeks. A final Safety Board report on the cause of this accident will be issued next year. Safety recommendations may be issued at any time. ### ========================================================== NTSB says United Flight 826 pushed up, then down WASHINGTON (Reuters) - U.S. investigators released initial data on Tuesday on the United Airlines flight that hit severe turbulence over the Pacific Ocean Sunday, saying the plane was pushed up sharply, then downward in the incident. In a brief statement on the flight data recorder removed from the plane, the U.S. National Transportation Safety Board did not say what caused the accident that killed a 32-year-old Japanese woman and injured many more aboard United Flight 826. However, it said the accident was not caused by a movement of the pilots' control column, indicating the flight crew was not involved. It also noted that the aircraft moved up or down less than 100 feet, contrary to initial reports that it fell as much as 1,000 feet. The flight was buffeted at 31,000 feet about one hour and 31 minutes out of Tokyo on its way to Honolulu, the NTSB said. It said the aircraft experienced a sudden upward push of almost twice the force of gravity, combined with a wind shear that increased the plane's speed from 335 knots or about 385 miles per hour to 350 knots, or about 400 miles per hour. This was followed about six seconds later by a sharp downward push. Passengers and crew reported being flung to the ceiling of the plane's cabin by the incident. The Boeing 747, carrying 374 passengers and 19 crew, returned to Tokyo's Narita Airport. The NTSB is leading the investigation of the incident because it occurred over international waters and the aircraft was U.S. registered. The flight data recorder arrived in Washington around midnight Monday and was reviewed in the NTSB's laboratory. The board said it would continue its investigation with further analysis of the flight recorder data, interviews with passengers and crew aboard the aircraft, and reviews of air traffic control and weather records. It said it did not expect to issue any updates on the accident for several weeks and would not determine the final cause of the event until next year. The NTSB on Monday had warned that limited information might be gleaned from the flight data recorder because of its age. United Airlines, a unit of UAL Corp, issued a statement following the NTSB statement, saying it corroborated reports that ``the aircraft encountered turbulence of a rare severity, which subjected passengers and crew to significant gravitational forces.'' [...] ^REUTERS@ =================================================================