For Pakistan, may 22 is a dark day: just this week, a Pakistan international airliner crashed in a residential area near Karachi airport after resuming civil aviation flight from the outbreak. This is a heavy blow to Pakistans aviation industry, which has just begun to resume operation, and it also casts a thick shadow on the worlds civil aviation industry, which is preparing to recover from the epidemic.
As the first major air crash after the outbreak of the epidemic, especially at the time when the aviation industry is preparing to recover from the epidemic, this air crash has undoubtedly attracted great attention. The plane was A320 (ap-bld), 15 years old. It is worth mentioning that this aircraft originally belonged to China Eastern Airlines (2004-2014), with the aircraft number of b-6017 (now used by a Boeing 737 of China Eastern Airlines), which was sold by China Eastern Airlines in 2014. The selling time is ten years old and has entered the aircraft replacement cycle (the average age of Chinese fleet is about 7 years). Since the aircraft has been sold to pakistania for nearly six years, unless it is as cheeky as pompeio, the pot will not fall on China Eastern.
China Eastern b-6017, later sold to pakistania
The plane that crashed
After the air crash, the author first collected all kinds of information to analyze the air crash. However, one of the tricky points of the crash is that the aircraft is not equipped with ADS-B equipment, which makes it impossible to display the flight status of the aircraft at that time on the flight information website of such real-time aircraft as flightradar24, and also has a certain impact on the analysis of the situation during the crash. Fortunately, fr24 is able to restore the altitude data of the plane before the incident with the receiver of local aviation enthusiasts through other technical means. Because the plane crashed in densely populated areas, there were a large number of witnesses, and even people took pictures of the plane in the air before the crash. At the same time, the recording of the communication between the pilot and the air traffic controller before the crash was also released, which brought great convenience to the preliminary analysis of the crash.
The flight information of fr24 on board is very incomplete due to the fact that the crashed aircraft does not have ADS-B equipment
Then fr24 finally restores the altitude curve of the aircraft using the receiver data
According to reports, the plane landed once before the crash, but finally gave up the landing and went around. Unfortunately, the plane crashed on the second landing. According to the Pakistan Civil Aviation Administration, before the crash, the captain said the front landing gear was faulty. The captains conversation with the tower also showed that the planes engine had failed and was losing power. It can be seen from the flight data that when the aircraft lands again after the go around, it will descend at a rate of 1250 feet per minute at a height of 500 feet.
Pilot: were flying right here. Were losing the engine
Pilot: help, help, help, Pakistan 8303
Tower: 8303 both runways are cleared and can land
According to eyewitness testimony, an engine was seen on fire before the crash. According to the photos taken at the scene before the crash, it can be seen that there are black marks under the engine shell of the aircraft, which are suspected to be the marks after the ground friction and fire. According to the official confirmation of Pakistan that there is a problem with the landing gear of the aircraft, it can be speculated that in the first landing, due to the failure of the landing gear, the engine friction on the ground will be damaged. When the pilot finds the landing abnormality, he immediately chooses to go around, but the engine is damaged in the previous landing, which makes the power of the second landing insufficient or even the engine stops. Finally, the aircraft stalls and crashes due to the lack of altitude and power.
The area where the plane crashed is very close to the runway
This is most likely the case when the plane first landed
According to the pilots experience, when encountering an unexpected situation in flight, as long as there is sufficient posture, that is, enough altitude or speed, there will be enough time for emergency. Whether its speed in exchange for altitude or speed in exchange for altitude, the pilot can have enough space for strain. However, when preparing for landing on the runway after approach, the aircrafts altitude is low and its speed is slow, which is in a situation of extremely low energy. Specific to the plane crash in Pakistan, due to the low altitude (the final data height is only about 180 meters), and the lack of power caused by the suspected engine failure of the aircraft, it is in a very dangerous situation, making the pilot lack of energy. Karachi airport is not surrounded by a large corn field or a large river, which eventually leads to pilots failure to try to land outside the airport and finally crash in the residential area.
When I discussed the crash with the Airbus pilots, I found that the crash was quite similar to the accident Capital Airlines encountered at Macao airport in 2018. On August 28, 2018, in the event of Capital Airlines Macau airport, due to the heavy landing of the aircraft and the damage of the landing gear in front of the aircraft due to wind shear, the damaged landing gear debris caused the engine damage. The pilot immediately gave up landing and chose to go around, and after confirming the situation of the aircraft, he chose alternate landing at the nearby Shenzhen airport to obtain better special situation handling guarantee, and finally successfully landed the aircraft safely.
In the event of Capital Airlines Macau airport in 2018, the front landing gear was completely damaged and debris was sucked into the engine, causing serious damage
From this, the author can draw a preliminary conclusion: when Pakistan 8303 flight landed for the first time, the engine was wiped due to the landing gear failure, and the captain did not choose to continue landing forcibly to stop the aircraft on the runway, but subconsciously chose to go around. However, the engine was damaged during the ground cleaning before, which led to the engine power output dropping seriously or even stopping during the second landing, resulting in the aircraft stalling and crashing in the residential area outside the airport during the landing phase. At the first time, the air crash said that all 107 people on board were killed, and there were no Chinese citizens on board. However, subsequent reports showed that there were many survivors on board. So far, more than 50 survivors, including a banker, have been found. Considering the altitude and speed of the plane at the time of the crash, there will be many survivors indeed.
Rescue the wounded at the scene of the air crash
As the first serious air crash in the post epidemic era, the air crash has undoubtedly brought great alert to the aviation industry. As a result of the epidemic, a large number of aircraft are parked for a long time, which needs to be strictly guaranteed before flying, and the huge losses of airlines in recent months are bound to have a significant impact on the maintenance and support of the aircraft. Landing gear failure is a relatively obvious accident symptom caused by insufficient maintenance, which leads to the occurrence of accidents. This is also what the Civil Aviation Administration emphasized at the recent analysis meeting of civil aviation safety operation situation: in the period of normalization of epidemic prevention and control, the safety work must not be relaxed, to ensure that the safe operation of civil aviation is stable and controllable, and not to cause disorder to the epidemic prevention work.
It is hoped that Pakistans international air crash will give a wake-up call to the worlds civil aviation industry, which is preparing to recover from the epidemic, and that the safety work during the epidemic prevention and control period must not be relaxed. As for CAAC, the flight volume has gradually recovered to the pre epidemic level in the first stage of comprehensive recovery, it is necessary to learn from Pakistans air crash lessons to ensure safe flight.