Sichuan flight 8633 blown windshield
It seems that physical issues with aircraft are all over the news right now, with the latest being Sichuan Airlines flight 8633. On the 14th of May 2018, Sichuan Airlines flight 8633 departed Chongqing, China for a scheduled passenger flight to Lhasa, the capital of the Tibet Autonomous Region (the area of Tibet in the People’s Republic of China).
Scheduled flights in the area didn’t start until 1965, when navigation aids and flight computers became reliable enough to allow for safe crossing. But flying to Lhasa is still a challenge, even with modern aviation technology. The Tibetan Plateau, located to the west of the Sichuan province, is the highest region on earth, with an average elevation of 16,000 feet (Mount Everest has an elevation of 29,000 feet and is located on Tibet’s border with Nepal). The region is particular dangerous for flying, with high mountains, deep gorges, violent turbulence and 200mph (320 km/h) winds.
Lhasa Gonggar Airport is the largest airport in the region, serving as an aviation hub for Tibet with daily flights serving major Chinese cities. The airport elevation is 11,710 feet (3,570 meters) and is surrounded by mountains ranging from 17,000 to 20,000 feet (5,362-6,126m). The runway is 4,000 meters (13,000 feet), allowing it to handle wide-bodied aircraft in the thin Tibetan air. As the wind picks up in the afternoon, most scheduled flights into the airport are in the morning. So it’s no surprise that pilots flying in and out of Lhasa Gonggar Airport require special training in handling manoeuvres for high altitude.
Sichuan Airlines (Chinese: 四川航空) is one of the seven airlines (all based in China) that fly in and out of Lhasa Gonggar. Their major hub and headquarters is in Chengdu, the Sichuan capital, at Chengdu Shuanliu International Airport. The airlines also offer scheduled domestic flights from Chongqing Jiangbei International, which is located to the southeast of the Sichuan province; that is to say, a scheduled flight from Chongqing to Lhasa passes over the Sichuan province, flying through Chengdu’s airspace.
Sichuan Airlines has 23 Airbus A319-100s in their fleet. The aircraft for the scheduled flight from Chongqing to Lhasa that day was serial number MSN4660, registration B-6419. The aircraft was built in 2011 and delivered to Sichuan Airlines in July of the same year. It had 19,942 flight hours.
I was lucky enough to discover Shimin on PPRunE who translated a number of articles from Chengdu Business News into English. Shimin works in the aviation industry and, although his English may not be as fluent as an official translator, he understands aviation terms, so I found his quotes much more readable than those from the mainstream British and American press. I have taken the liberty to fix some minor grammatical issues while taking care to ensure that Shimin’s original intent remains.
The scheduled flight 8633 departed on time from Chongqing with 128 souls on board. The weather was clear and visibility was good. The flight proceeded normally as they reached their cruising altitude of 9,800 metres (32,000 feet). Forty minutes into the flight, passing through the Chengdu air traffic control zone, it was clear that something had happened. The cabin crew were serving breakfast and passengers were dozing. Suddenly there was a loud bang heard throughout the aircraft. The aircraft shook and the oxygen masks dropped.
In the cockpit, Captain Liu was faced with an unexpected emergency. The inside layer of the right windshield cracked and an error illuminated showing an anti-icing failure.
There was no warning; suddenly, the windshield cracked and burst, making a loud noise. I looked up to see the co-pilot was hanging halfway out the window. Luckily, he had fastened his seatbelt. The cockpit items all flew into the air. Much of the equipment failed and the noise was so loud that I couldn’t hear the radio. The whole plane was vibrating so hard that I wasn’t able to read the instruments.
The right main windshield had suddenly cracked with a bang and then separated from the aircraft, sucking the co-pilot out of his seat. The pressure dropped and with it the temperature. The three pilots were in short sleeves and now suddenly it was -40°C in the cockpit; cold enough that the captain knew they were at risk of frostbite. The sudden loss of pressure had also caused multiple instruments to fail, including both Flight Control units (FCU). According to China Aviation review, the FCUs failed because they were sucked out.
I wasn’t sure about why there were three pilots in the cockpit but Shimin was kind enough to explain that in western China, high plateau operations are always flown by three-man crews, where two are qualified captains.
Chinese airlines keep the three-man system in many daily routes, especially in remote, bad conditions and long-haul operations. It does cost a lot and the practice is often mocked but it is safer in my opinion. In such a three-man system, one of the key considerations is the ranking among the three men. In Chinese airlines, the practice is that the top one is designated as the Lead Captain, even if he is in the observer’s seat when any accidents happen.
The three-man system was one of key factors for this successful landing. With the help of the second captain, many checklists were implemented before landing while Liu was left to concentrate on “Aviate” and make every decision timely and correctly. As the Lead Captain, Liu is the highest with over 13,000 flight hours, the secondary captain had about 8,000 flight hours and FO was a young man with about 2,800 hours.
Captain Liu punched 7700 into the transponder, alerting air traffic control to the fact that he had an emergency. The captain descended rapidly from 32,000 to 23,500 feet — passengers in the cabin described it as a free fall or suddenly becoming weightless. The aircraft continued to shake violently. I’m sure the captain wanted to get down more quickly but the area safety altitude was 22,100 feet. He had to wait until they were clear of the high ground and on the approach to Chengdu in order to descend to 10,000 feet.
The press asked him more details and I love his matter of fact answers (again translated by Shimin)
Like in the cabin, when the cockpit loses pressure, the oxygen mask will automatically fall off. Hypoxia is not a big issue. Also, the cockpit and the cabin are sealed and insulated, so the loss of pressure and the cold in the cockpit did not affect the passengers.
Yes, it was a completely manual operation, I had to visually rely on my own judgement. Much of civil aviation is automatic operation, but this time the equipment was of no help. I’ve flown this route over a hundred times, I should say everything about flying here is familiar to me.
At the time, I just wanted to operate the aircraft safely, I was unable to pay attention to my and my co-pilot’s physical condition. In order to avoid further damage to him and to the passengers, the first thing I had to do was reduce the speed and then try to descend as quickly as possible. The noise was great and the automatic equipment can’t help. Completely by and visual, I had to rely on perserverance to grasp the stick to complete the return [to Chengdu] and the safe landing. My body should have been a very big wobble.
I feel like I’m a very big wobble just reading about it! Once the aircraft had lost speed, the first officer was able to drag the second captain back in from the cockpit.
There was no power in the cabin and the PA system didn’t work. Although the aircraft was in control, the passengers panicked, with some beginning to vomit. A flight attendant began to shout to be heard over the passengers.
Please believe us, we have the confidence that we are able to take you to the ground. We have the confidence to land safely!
Although initial reports said that the tyres had burst on landing, the Captain was clear that this wasn’t true.
The aircraft was overweight and the thrust reverser was not working. We needed longer than the normal taxing distance, which means that the tire rubs longer and causes the temperature too high. The tire automatically deflated–this is a protection, not a flat tire.
When compared to Captain Sully, Captain Liu pointed out that he had much more in common with the British Airways 5390 incident, in which the captain was partially blown out of a newly installed windscreen which had not been bolted in correctly.
However, that was in a BAC One-Eleven, a British short-range jet airliner where the windscreen is attached from the outside with bolts. The Airbus A319 windshield is installed into a frame from the inside, so it can’t detach but must have failed completely across all layers after the crack.
This photograph appeared with only the attribution “as seen on social media” and I haven’t found a way to verify it; however apparently it is the co-pilot’s uniform, or at least the remains of it, as recovered after the incident.
I don’t usually include a lot of local news reports but I love the fact that these are available because Shimin took the time to translate them. The following is a passenger’s note to friends that was published on Chinese social media and translated by Shimin. The language and metaphors are quite beautiful, even in translation.
In May 14, 2018, 3U8633, Chengdu Shuangliu Airport, I just experienced a life and death.
From Chongqing to Lhasa, the route that I had taken countless times, I slept on my seat as usual. The stewardess woke me up to the breakfast time. As usual, I reckon how long it will take to get to Lhasa. The shock always happens in a sudden break. Suddenly, there was a loud noise at the top of the plane, the cabin suddenly darkened, the oxygen mask fell in front of me, and the plane began to fall as fast as it was, just for a moment. My mind was blank. After seeing around, it was confirmed that it was not my dream. Then I wore mechanically the oxygen mask according to the instructions of the stewardess. After the blanks, there was a surge of fear. I was clearly know I was going to experience an bad accident, and I had no way to do it. When I realized that I couldn’t do anything about survival, depression, fear and panic began to fill me. I always thought I was not afraid of death, but when you really faced death and could do nothing, I was like a fish that had just been put into the boiling water and was attacked by little bits of death. I can see clearly that the icebergs beneath the plane and they are only about a kilometer away. Real depression just started. I feel the despair in the eyes of the passengers around, perhaps they can also feel my despair.
Of course, I am still alive and lovely now. Just like fairy tales, pilot has become hero in the twinkling of an eye. He gradually controlled the situation, changed direction, flew to Chengdu, and then landed on the runway of Shuangliu Airport. Hanging heart also slowly landed, trance seems to have gone through a dream, to be thrilling, and finally returned to peace. I am seating in the cabin now, waiting for the trailer to pull the plane to safe area and all the cabin is just back to life.
It’s not clear how I feel now. To escape or to die? Thank you for pilots and stewardess. Save me alive without death at such a young age. I can only say one thing: it’s nice to be alive.
Sichuan 3U8633 from Chongqing to Lhasa diverted to Chengdu. Lost one windshield at FL332. Descend to FL240 due to high terrain (@flightradar24 data). Cabin decomp. FCU failure and some parts sucked out. Landded safely with bust tires. One pilot and one cabin crew injured. pic.twitter.com/8aViRZoOE0
— ChinaAviationReview (@ChinaAvReview) May 14, 2018
The majority of the passengers were put on the next flight to Lhasa, arriving at 12:09 local time. Captain Liu’s wife said that she phoned him to see that he was all right but he told her that he was busy and that she shouldn’t go to Chengdu to meet him.
I’m not very worried about him. He has been flying in the Air Force and Sichuan Airlines for many years. I really believe in his technology. His character is calm and steady.
The first officer was treated for scratches and a sprained wrist but suffered no serious injury.
The Civil Aviation Administration of China (CAAC, the Chinese aviation authority) will be leading the inquiry with teams from the French BEA and from Airbus already in China to support the investigation. They’ve already confirmed that the right cockpit windshield on the Sichuan Airlines Airbus A319 was an original part of the aircraft which was assembled at the Tianjin plant in China in 2011 and came into service later the same year. According to the logs, the windshield has never been replaced or undergone any maintenance.
I’m looking forward to finding out more (and to read more translations by Shimin!).