TransAsia Airways Flight 235 was a domestic flight from Taipei to Kinmen, Taiwan. On 4 February 2015, the aircraft serving the flight, a 10-month-old ATR 72, crashed into the Keelung River around 5 km (3.1 mi; 2.7 nmi) from Taipei Songshan Airport, from where the aircraft had just departed. On board were 58 people, 15 of whom survived with injuries.
Two minutes after takeoff, the pilots reported an engine failure. After climbing to a height of 1,630 ft (500 m), the other engine, still operating normally, was mistakenly shut down. The aircraft lost altitude, banked sharply to the left and clipped a taxi traveling west on the Huandong Viaduct (causing injuries to two more persons), then the viaduct itself, before crashing into the river below.
Flight 235 was the second fatal accident involving a TransAsia Airways ATR aircraft within seven months; Flight 222 had crashed on 23 July 2014, also with 58 people on board. On that flight, 48 people had died.
Flight 235 departed Taipei Songshan Airport at 10:52 Taiwan time (02:52 UTC), for its destination of Kinmen Airport, with 53 passengers and five crew members on board. Shortly after take-off, a fault in the autofeather unit of the number-2 engine caused the automatic take-off power control system to autofeather that engine. The flight crew misdiagnosed the problem, and shut down the still-functioning number-1 engine. The aircraft reached an altitude of 1,630 ft (500 m) and then began descending until it crashed. The last pilot communication to air traffic control was: "Mayday, mayday, engine flameout." At 10:55, the aircraft crashed into the Keelung River, on the border of Nangang District of Taipei and Xizhi District of New Taipei.
The crash was recorded by dashcams in several cars travelling west along the elevated Huandong Viaduct next to the river. The aircraft, flying level, first cleared an apartment building. Then it rolled sharply, at nearly a 90° bank angle, left wing down. As the aircraft flew low over the elevated viaduct, its left wingtip struck the front of a Volkswagen Caddy taxi travelling west on the viaduct, and the outboard section of the wing was torn off when it struck the concrete guardrail at the edge of the viaduct. The aircraft continued its roll and struck the water upside down, breaking into two main pieces. The collision with the taxi and the viaduct was captured in footage from a dashcam in a car travelling a short distance behind the taxi, and debris from the plane's wing and pieces of the viaduct's guardrail were thrown across the road surface. Two people in the taxi suffered minor injuries.
At the time of the accident, no adverse weather phenomena were observed. At 11:00, the cloud base at Songshan was about 1,500 ft (460 m), the visibility was unrestricted, and a light breeze was blowing from the east at 10 knots (19 km/h; 12 mph). The temperature was 16 °C (61 °F).
The aircraft involved in the accident was an ATR 72-600 twin-turboprop, registration B-22816, MSN 1141. It first flew on 28 March 2014, and was delivered to TransAsia Airways on 15 April 2014. The left Pratt & Whitney Canada PW127M engine was replaced in August 2014.
The passenger manifest was composed of 49 adults and 4 children. Thirty-one passengers were mainland Chinese; many were visitors from Xiamen on a six-day tour of Taiwan. The remaining 22 passengers were Taiwanese.
The flight crew consisted of two pilots, both ranked as captains; the captain was Liao Chien-tsung, 42, with a total of 4,914 flight hours (including 3,401 hours on the ATR 72) and the co-pilot was Liu Tze-chung, 45, with a total of 6,922 flight hours, including 6,481 hours on the ATR 72. Also, an observer, Hung Ping-chung, 63, was seated in the cockpit jump seat, who had a total of 16,121 flight hours, 5,314 of them on the ATR 72. Two flight attendants (including Huang Ching-ya) were working as cabin crew. All crew members were Taiwanese citizens; the co-pilot was a dual New Zealand–Taiwanese citizen.
Taipei police and fire departments received dozens of calls from eyewitnesses almost immediately after the crash. The Taipei Fire Department, military, and volunteer rescue workers arrived at the crash scene within minutes, and reached the survivors by boat around 35 minutes after the crash. They began removing survivors from the rear section of the semisubmerged fuselage and ferried them to shore in inflatable boats. Divers were forced to cut the seat belts of dead passengers, located mostly in the front section, to remove their bodies. That work was made difficult by low visibility under water.
The aircraft's flight recorders were recovered shortly after 16:00 that day. After 20:00, cranes were used to lift large sections of the fuselage ashore.
Of the 58 people on board the flight, only 15 survived. One of the two flight attendants, Huang Ching-ya, survived.
Some media outlets reported anonymous claims that the pilot had complained of "engine abnormalities" and asked for an inspection of the aircraft prior to take-off, but that the request had been refused. This assertion has been denied by both TransAsia Airways and the Civil Aeronautics Administration, the former of whom has released the maintenance records for both powerplants, both propellers, and the airframe.
Following the accident, TransAsia Airways changed its website and social media branding to greyscale images, in mourning for the presumed deaths of the passengers. On 5 February, TransAsia retired the flight number GE235, changing it to GE2353.
The spokesperson of the Office of the President of the Republic of China reported that President Ma Ying-jeou was very concerned about the accident and had given orders to the Executive Yuan and related authorities to provide maximum assistance with the rescue. Immediately after the accident, the president of the Executive Yuan, Mao Chi-kuo, contacted the Ministry of Transportation and Civil Aeronautics Administration to instigate an investigation into the crash, and the minister of national defense to prepare the military for the rescue. The final report on the investigation carried out by Taiwan Transportation Safety Board was released on 30 June 2016.
Over half of the passengers on board the aircraft were Chinese. On 5 February 2015, Xi Jinping, the General Secretary of the Chinese Communist Party, released a statement, ordering that accurate information on the aircraft be obtained as quickly as possible, and that "assistance [be provided] in treating the injured". On the same day, Chinese Premier Li Keqiang instructed relevant departments to obtain accurate information from Taipei as quickly as possible.
The Taiwanese Aviation Safety Council (ASC) led the investigation into the accident. The French Bureau of Enquiry and Analysis for Civil Aviation Safety (BEA) represented the country of manufacture, and the Transportation Safety Board of Canada represented the country of engine manufacture. Other parties to the investigation included the Taiwanese Civil Aeronautics Administration, the operator (TransAsia), the aircraft (ATR) and engine (Pratt & Whitney Canada) manufacturers, and Transport Canada. The cockpit voice recorder and flight data recorder were recovered on the evening of 4 February, and the data were analysed. According to the executive director of the ASC, Thomas Wang, the aircraft's right engine triggered an alarm just 37 seconds after takeoff. Whereas the crew reported a flameout, according to Wang, data showed the right engine had in fact been moved to idle power. Soon the right engine failed to produce enough thrust for its rotating propeller, lapsing into auto-feathering. A restart was attempted, but the aircraft crashed 72 seconds later.
On 6 February, investigators revealed that the left engine, which does not appear to have had suffered a malfunction, had been manually shut off, while cautioning that the investigation was "too early to say if human error was a factor". Investigators released the following preliminary sequence of events: