Korean Air Flight 801 was a scheduled international passenger flight operated by Korean Air, from Gimpo International Airport, Seoul to Antonio B. Won Pat International Airport, Guam. On August 6, 1997, the Boeing 747-300 operating the flight crashed on Bijia Peak, south of Nimitz Hill, in Asan-Maina, Guam, while on approach to the destination airport, killing 229 of the 254 people aboard, making it the deadliest aviation accident to occur in American dependent territory, and the fourth-deadliest aviation accident on American soil overall.
The National Transportation Safety Board cites poor communication between the flight crew as the probable cause of this accident, along with the captain's poor decision-making on the non-precision approach.
Background
Aircraft
The aircraft involved in the accident, manufactured in 1984, was a Boeing 747-3B5, registered as HL7468, which was delivered to Korean Air on December 12, 1984. The plane was equipped with four Pratt & Whitney JT9D-7R4G2 engines.
Crew
The flight was under the command of 42-year-old Captain Park Yong-chul. The captain had close to 9,000 hours of flight time, including 3,192 on the Boeing 747, and had recently received a flight safety award for successfully landing a 747 that had suffered an engine failure at low altitude. Park was originally scheduled to fly to Dubai, United Arab Emirates, but since he had not received enough required rest for the Dubai trip, he was reassigned to Flight 801. The first officer was 40-year-old Song Kyung-ho, who had more than 4,000 hours flying experience, with 1,560 of them on the Boeing 747. The flight engineer was 57-year-old Nam Suk-hoon, a veteran pilot with more than 13,000 flight hours, 1,573 of which were on the Boeing 747.
Accident
In 1997, the route was normally flown by an Airbus A300, but since Korean Air was charged with transporting Chamorro athletes to the South Pacific Mini Games in American Samoa, the airline substituted the larger 747-300 to fly the route that night.
Flight 801 departed from Seoul-Kimpo International Airport (now Gimpo International Airport) at 8:53 pm (9:53 pm Guam time) on August 5. It carried three flight crew members (the two pilots and the flight engineer), 14 flight attendants, and 237 passengers from four countries, 254 people in total. In the summer, Guam is a popular tourist destination among South Koreans, and many passengers were travelling with family. There were many children on the flight; Korean media stated the presence of numerous children with their families, while the NTSB reported the presence of only three children between the ages of 2 and 12 and three 24 months old or younger. Six of the passengers were Korean Air flight attendants, who were deadheading.
The flight experienced some turbulence but was uneventful until shortly after 1:00 am on August 6, as the jet was preparing to land. It was raining heavily in Guam, so visibility was considerably reduced, and the crew attempted an instrument landing. The glideslope Instrument Landing System (ILS) for runway 6L was out of service, but Captain Park mistakenly believed it was in service, and at 1:35 am, he managed to pick up a signal that was later identified to be from an irrelevant electronic device on the ground. First officer Song and flight engineer Nam both noticed that the aircraft was descending very steeply, and remarked several times that the airport "is not in sight." Despite protests from Nam that the detected signal was not the glide-slope indicator, Park continued the approach, and at 1:42 am, the aircraft crashed into Bijia Peak just short of a VHF omnidirectional range navigation beacon about 3 nmi (3.5 mi; 5.6 km) short of the runway, at an altitude of 660 ft (200 m).
Of the 254 people on board, 229 died as a result of the crash. One survivor, 36-year-old Hyun Seong Hong, also spelled Hong Hyun Sung) of the United States, occupied seat 3B in first class, and said that the crash occurred so quickly that the passengers "had no time to scream" and likened the crash to "a scene from a film."
Rescue
The rescue effort was hampered by the weather, terrain, and other problems. Emergency vehicles could not approach because a fuel pipeline, destroyed by the crash, blocked the narrow road. United States Navy Seabees of NMCB-133 and NMCB-40 were some of the first on the scene and used their earth-moving equipment to clear roadways and timber from the crash-site approach. The Seabees used backhoes to crack open the still-burning plane to rescue survivors and erected mortuary tents for first responders. Confusion arose over the administration of the effort; the crash occurred on land owned by the United States Navy, but civil authorities initially claimed authority. The hull had disintegrated, and jet fuel in the wing tanks had sparked a fire that was still burning eight hours after impact.
Rika Matsuda
Governor Carl Gutierrez found 11-year-old Rika Matsuda, from Japan, who had boarded the flight with her mother, 44-year-old Shigeko. They were heading to Guam on vacation. Rika Matsuda described to interpreters what happened to her mother and her. Luggage piled on the girl and her mother as the crash occurred; Rika Matsuda said her mother, unable to free herself, asked her to leave. Shigeko died in the fire. After escaping from the aircraft, Rika discovered a surviving flight attendant, Lee Yong Ho. They stayed together until Gutierrez discovered them. Rika Matsuda, treated at Guam Memorial Hospital in Tamuning, was released on August 7, 1997, and was reunited with her father, Tatsuo Matsuda. The two were then escorted to the Governor House, where they were the guests of Gutierrez and the First Lady of Guam, Geri Gutierrez, for several days; afterward, Rika and Tatsuo Matsuda flew to Japan.
Investigation and probable cause
The U.S. National Transportation Safety Board (NTSB) investigated the accident, as it occurred in U.S. territory.
A special weather observation made at 01:32, 10 minutes before the impact, reported:
Wind 090° at 6 knots; visibility—7 miles; present weather—shower vicinity; sky condition—scattered 1,600 feet, broken 2,500 feet, overcast 5,000 feet [above ground level]; temperature—27 °C; dew point—25 °C; altimeter setting 29.85 inches Hg; remarks—showers vicinity northwest-northeast.
Another special weather observation made at 01:47, five minutes after the impact, reported:
Wind variable at 4 knots; visibility—5 miles; present weather—light rain shower; sky condition—few 1,500 feet, scattered 2,500 feet, overcast 4,000 feet; temperature—26 °C; dew point—24 °C; altimeter 29.85 inches Hg.
The crew had been using an outdated aeronautical chart that was missing a 724 ft (221 m) obstruction symbol depicted at the NIMITZ VOR, and that map stated the minimum safe altitude while crossing the NIMITZ VOR for a landing aircraft was 1,300 ft (400 m) as opposed to the updated altitude of 1,440 ft (440 m). Flight 801 crashed near the NIMITZ VOR, which is situated on Bijia Peak at an altitude of 680 ft (210 m) at 1:42 am, when it descended below the minimum safe altitude of 1440 ft during its landing approach. The report also identified that the captain may have mistakenly believed that the airplane was closer to the airport than it was, and confusion may have existed about the location of the distance measuring equipment (DME) in relation to the airport, with the crew anticipating the VOR/DME to be located at the airport. The DME was sited at the NIMITZ VOR some 3.3 nmi (3.8 mi; 6.1 km) from the airport and such a configuration had not been part of Korean Air's simulator training, the crew's training for such non-precision approaches having been carried out in scenarios where the DME was located at the airport. Nevertheless, the correct DME distances were shown on the approach chart.
The NTSB was critical of the flight crew's monitoring of the approach, and even more critical of why the first officer and flight engineer did not challenge the captain for his errors. Even before the accident, Korean Air's crew resource management program was already attempting to promote a free atmosphere between the flight crew, requiring the first officer and flight engineer to challenge the captain if they felt concerned. The flight crew only began to challenge the captain six seconds before impact, though, when the first officer urged the captain to make a missed approach. According to the cockpit voice recorder, the flight crew suggested to the captain that he had made a mistake, but did not explicitly warn him. The flight crew had the opportunity to be more aggressive in its challenge and the first officer even had the opportunity to take over control of the aircraft and execute a missed approach himself, which would have prevented the accident, but he did not do this. Despite examining Korean Air's safety culture and previous incidents, the NTSB was unable to determine the exact reasons why the flight crew failed to challenge the captain, but at the same time noted that "problems associated with subordinate officers challenging a captain are well known".
Air traffic control (ATC) also played a role in the accident. The center/approach controller, 39-year-old Kurt James Mayo, did not adhere to standard ATC procedures and failed to monitor the aircraft during its descent. Specifically, he did not monitor the flight after the crew switched to the tower frequency as required, did not give a position advisory to the flight crew when clearing them for the approach (which would have advised them to cross-check their position on the radar with that of other flight instruments), and did not monitor the flight on the terminal radar display, which showed the terrain in the area because radar service had been terminated at the time. The NTSB said that had Mayo followed the procedures, the accident could have been prevented or at least reduced in severity. The tower controller, Marty Irvin Theobald (also 39), was also criticized for not alerting the crew, as Mayo had been unaware of the aircraft's low altitude, and did not provide an alert to him.
The NTSB also criticized the emergency responders for their delayed rescue operation, citing that most of the factors that delayed the response were preventable. These factors included ATC's initial unawareness of the accident, a brake failure on a fire truck, and a delayed notification of the fire department. The NTSB also concluded that at least one person who survived the initial crash could have recovered had the response not been delayed.
The NTSB presented its findings on March 24, 25, and 26, 1998, at the Hawaii Convention Center in Honolulu.
The section of the report entitled "Probable Cause" concluded:
The National Transportation Safety Board determines that the probable cause of this accident was the captain's failure to adequately brief and execute the non-precision approach and the first officer's and flight engineer's failure to effectively monitor and cross-check the captain's execution of the approach. Contributing to these failures were the captain's fatigue and Korean Air's inadequate flight crew training.
Contributing to the accident was the Federal Aviation Administration's intentional inhibition of the minimum safe altitude warning system at Guam and the agency's failure to adequately manage the system.
The investigation report stated that a contributing factor was that the ATC Minimum Safe Altitude Warning (MSAW) system at Antonio B. Won Pat International Airport had been deliberately modified to limit spurious alarms and could not detect an approaching aircraft that was below minimum safe altitude. The probable cause of the accident was the captain's poor execution of the non-precision approach, the captain's fatigue, poor communication between the flight crew, and Korean Air's lack of flight crew training.
Passengers
Deaths and injuries
Of the 254 people on board, 223 people—209 passengers and 14 crew members (all 3 flight crew, and 11 cabin crew)— died at the scene.
Of the 31 occupants found alive by rescue crews, 2 died en route to the hospital and a further 3 in hospital. Among the survivors, 16 received burn injuries. The 26 survivors were initially treated at Guam Memorial Hospital in Tamuning or at Naval Hospital Guam in Agana Heights. Four were subsequently transferred to the U.S. Army Burn Center in San Antonio, Texas and eight to University Hospital in Seoul. On October 10 of that year, one passenger died from injuries suffered in the crash, bringing the number of fatalities to 229 and the number of survivors to 25.
Twenty-two passengers and three flight attendants survived the crash with serious injuries.