Salvage teams attempting to recover the flight data and cockpit voice recorders from a Lao Airlines ATR 72-600 that crashed into the Mekong River in southern Laos on October 16 have narrowed the search area from some 650 feet to about 80 feet, but zero visibility, limited mechanical means, a five-knot river current and a lack of manpower have hampered their effort.
The regional turboprop, en route from the Laotian capital Vientiane to the southern city of Pakse, crashed on approach to Pakse International Airport, killing all 44 passengers and five crewmembers. The search for the FDR, CVR and sections of the aircraft continue from a barge located in the middle of the river, some 1,000 feet from the island of Don Phaling.
Four members from the French BEA (Bureau d'Enquêtes et d'Analyses) and four representatives of ATR arrived in Laos on October 19 to assist in the investigation and salvage operation undertaken by the Thai navy and Laotian divers, who lack the expertise to recognize the recording devices and parts of the aircraft. With no salvage experience and limited economic means, the divers use concrete blocks for anchors, buckets for buoys and ropes to measure parts of the fuselage submerged under water. The divers must refill their oxygen tanks on shore, which further impedes their progress.
Tensions ran high on October 21, as the Thai navy team departed back to Thailand, leaving seven Laos divers to retrieve the recorders. The team believed that they had located the FDR and CVR; however, due to the late hour they decided not to attempt a recovery.
On October 22 the Laotian divers successfully secured a 30-foot section of the fuselage with the use of a crane, ropes, chains and physical manpower. Lao Airlines manager of flight standards and safety Phonesuthat Thammachalurne and Laotian director of civil aviation Yakua Lopangkoa confirmed that air traffic controllers were monitoring the approach when they observed that the aircraft’s altitude had dropped too low as it approached the airport. The crew also failed to activate the pilot-controlled airport lighting to high intensity. Reports indicated broken clouds prevailed at 1,000 feet agl. ATC instructed the pilot to perform a go-around. Seconds later, controllers lost communications with the aircraft.
The turboprop crashed less than 2,000 feet from the river bank of Don Phaling before plunging into the Mekong. Several government officials suggested that the aircraft’s landing gear touched down on the edge of the island before hitting the water. Investigators found three shallow indentations in a naturally cleared area on the bank, some 25 feet above the river. Debris from the aircraft, including small pieces of the airframe, scattered throughout the area.
The pilot, a 58-year-old Cambodian national with 30 years of flight experience, had flown for the carrier for four years.
Lopangkoa reported that rain was falling at the time of the accident. However, he declined to comment further about the weather until crews retrieve the cockpit voice and flight data recorders. He did confirm that two aircraft landed earlier without incident on the day of the crash.
The October 16 crash marked the third fatal accident for Lao Airlines since it started operations in 1976 under the name Lao Aviation. In 1993, all 18 occupants died when a Harbin Yunshuji Y-12-11 struck trees in heavy fog, crashed and immediately caught fire. In 2000 a second Harbin Yunshuji Y-12-11 crashed in the mountains while on approach, killing eight passengers.
Among five other reported incidents, a Cessna Grand Caravan made a successful emergency landing in a rice field due to engine failure during a flight in 2009, said Lopangkoa. He also reported that in April of this year a deHavilland Twin Otter 300 took off with a known landing gear problem and crash landed 650 feet from the end of the runway.
Lao Airlines has operated a fleet of ATR 72s for the last 10 years. The carrier also operates Airbus A320s and Chinese-made MA-60s for regularly scheduled short-haul domestic flights and routes to China, Thailand, Cambodia, Korea and Vietnam.