China Airlines 611 was a regular, scheduled flight between Taipei - Chiang Kai-shek International Airport (TPE) and Hong Kong - Chep Lap Kok International Airport (HKG). Operated by a Boeing 747-209B, the aircraft crashed into the Taiwan Strait, which separates the island of Taiwan from mainland China, due to metal fatigue in the fuselage. This accident killed all 225 people onboard the aircraft, including 206 passengers and 19 crew members.

The aircraft (B-18255)

The Boeing 747-200 that was operating on the route (registration: B-18255, originally registered as B-1866) was the only remaining aircraft of this type in the fleet, as the others had been converted to freighters operating for the cargo division of China Airlines. B-18255 was actually operating its last commercial flight for China Airlines, and had been sold to Orient Thai Airlines, a charter airline based in Bangkok, Thailand. The aircraft was to return to Taipei after the flight to Hong Kong, and would then be under the control of Orient Thai Airlines. This, unfortunately did not happen.

中華航空波音747編號B-18255_20011010
The aircraft was on its last revenue service. Photo: 余亞瑟 via Wikimedia Commons

This aircraft had been delivered to China Airlines in 1979, and had logged 64,394 airframe hours, according to aviation-safety.net. It had operated 21,180 flight cycles prior to this flight.

The flight (CI 611)

This flight was relatively routine for China Airlines, as this route was operated multiple times daily. In addition, the weather conditions were reported as fine and relatively warm, and therefore weather wasn't a safety concern.

The majority of passengers and all crew members (209 of 225) were Taiwanese. Some passengers were Chinese and some were residents of Hong Kong. 114 passengers were tourists traveling to China on scheduled tours, and other prominent passengers on this service included a Taiwanese legislator and a politician.

At 15:16, the flight was cleared to climb to about 35,000 feet (11,000 m). Three minutes later, the aircraft broke up in midair and contact was lost. Almost all remains were recovered, and flight recovery teams reported that most victims had extensive head wounds and injuries, but there had been no reports of foul play or fire.

Search and recovery

Since this accident happened in busy airspace, other nearby aircraft could see the crash site, and reported it to authorities. At 18:10, first responders were on scene and had found the remains of some victims. The governments of the People's Republic of China (mainland China) and the Republic of China (Taiwan) cooperated on this search, and this certainly did expedite the process of identifying the victims. China Airlines also requested that relatives of victims send blood samples to laboratories to help with victim identification. To date, 175 of the 225 victims' remains have been identified.

China Airlines Flight 611 fuselage reconstruction
Safety authorities reconstructed as much of the fuselage as possible to figure out what went wrong. Photo: Getty Images

Cause

Following the crash, an extensive investigation was launched. The final report cited inadequate maintenance as the main cause.

In February 1980, 20 years previous, the aircraft had operating flight CI 009 from Stockholm Arlanda Airport (ARN) to Taoyuan International Airport (TPE) via Jeddah and Hong Kong when it suffered a tail strike. On landing at Kai Tak Airport (demolished, formerly HKG), one of its two stops on this route, the plane's tail had scraped along the runway.

Instead of carrying out proper maintenance on the aircraft, the China Airlines engineering team simply installed a doubler over the damaged part of the aircraft. This was not sufficient according to Boeing's Structural Repair Manual (SRM). The constant use of the aircraft had enlarged the crack within the aircraft, which eventually led to the aircraft breaking up midair two whole decades later.

Conclusion

This accident sent shock waves through the aviation community, as it emphasized the importance of proper maintenance on aircraft, particularly aircraft that are involved in accidents. The Republic of China's Civil Aviation Administration (CAA) grounded all the Boeing 747-200 within China Airlines' fleet to ensure that they didn't have any cracks.

Source: Aviation Safety Net