The so-called 737NG (Next Generation), known as the 737-600, -700, -800 and-900 series, is also one of the most successful narrow-body models in Boeings history.
As the vast majority of 737 in operation worldwide currently belongs to 737NG (total operation volume is about 6 800, and 737 is also the main operation of domestic aviation enterprises), the number of shutdowns of 737 will increase further in the future due to the impact of crack incidents.
Why did 737NG stop flying?
In September, engineers on a 737 passenger cargo conversion mission discovered structural cracks on the fuselage of a 737-800 aircraft undergoing passenger cargo conversion, which was originally planned to be delivered to Amazons Prime Airlines.
According to foreign media reports, the location of the crack is the picklefork of the aircraft. Although there is no crash accident caused by the breakage of the picklefork in the world, the impact of the crack can not be underestimated because it is mainly used to connect the fuselage and wing of the aircraft.
According to reports, in the most extreme case, the fork break may cause 737NG airliner to lose control and crash at high altitude.
Its called a fork because its similar to a fork.
According to the design, fork should be able to withstand 90000 flight cycles, so this kind of event of crack occurring before the life cycle is particularly rare.
Subsequently, FAA issued airworthiness directive (AD), which requires that 30000 cycles of aircraft should be inspected within 7 days, and that the series of aircraft with more than 22600 cycles but less than 30000 cycles should be inspected within 1000 flight cycles of continuing flight.
The so-called flight cycle, in fact, refers to an aircraft boost and decompression, we simply understand as an aircraft landing and landing.
After inspection, about 5% of 737NG series aircraft were found to have cracks in the fuselage and were grounded. The probability of 5% is not low, but considering that most of the affected airliners are old airplanes with an aircraft age of about 20 years, the impact on airlines with relatively small fleet age should also be slightly smaller.
Southwest Airlines: Its hard to say.
At present, it is not known why the fork cracks occur. Regulators are trying to find potential causes from the aspects of aircraft design, materials and manufacturing process.
According to a Boeing statement, its technical experts are analysing the airlines inspection results and formulating the best maintenance plan. However, Boeing has not yet given a grounding schedule. According to aviation expertsestimates, the aircraft with cracks may take 60 days to repair.
The older the machine is, the more likely the crack will appear in 737
Will the fork crack event affect the 737max?
According to a Boeing spokesman, this failure does not affect the Boeing 737MAX and the special model 737.
How will the crack event affect 737NG?
The 737NG crack incident was discovered by accident. Before the incident was exposed, Fig. 737 had been flying with cracks for some time. Obviously, in order to ensure aviation safety, 737NG may usher in large-scale inspections worldwide, and the number of grounded flights will further increase.
737BCF has five production lines in China
Secondly, 737 series durable image may be affected.
737 is one of the most popular passenger-to-cargo aircraft, and a large number of decommissioned 737CL passenger aircraft have been put into air cargo business.
At present, Boeings most important passenger-to-cargo service is to convert 737-800 to 737-800 BCF, but due to the potential crack threat, the cost and time of future modification may rise.
Finally, passengers worries about the 737 series are sure to deepen. Since the 737MAX accident, it is not a good thing for Boeing that the 737 series has revealed major concerns. Foreign netizens have expressed their refusal to take the 737 series of passenger planes. If the impact of 737NG crack event is further expanded, the brand image of 737 may be hit again. By then, Boeing may have to think seriously about whether it wants to develop a new narrow-body airliner. Source: Liable Editor of Netease Aviation Special Paper: Lin Zhiheng_NY9285
Since the 737MAX accident, it is not a good thing for Boeing that the 737 series has revealed major concerns. Overseas netizens have expressed their refusal to take the 737 series of passenger planes.