According to the official news of China Commercial Aircraft, the jury composed of 63 academicians and experts in China recently agreed to pass the first flight technical review of the domestic large-scale passenger aircraft C919. It is recommended that after the completion of electromagnetic compatibility, taxiing and other test verification, the first flight can be released. Review.
This marks that China's first domestically produced large aircraft has taken another solid step toward the goal of the first flight!
However, the C919 has been off the assembly line for a year and a half, and the first flight has been postponed. The latest news is that the configuration of the first C919 prototype has been confirmed and will fly in April.
Why is the first flight so difficult?
According to the latest understanding, China Commercial Aircraft found in the ground static test that it can further reduce the weight of the aircraft because the wing is too strong. This improvement will be implemented on the next four prototypes.
At first glance, this news seems unreasonable. Isn't it good to have a strong wing? In fact, for passenger aircraft, under the premise of meeting flight safety, properly reducing the strength of the body can reduce the weight of the body and improve fuel economy.
In the test of the domestic regional airliner ARJ21, the structural strength was insufficient and the static test failed. The C919 may have some strength in the test, and proper correction is necessary.
Although the first flight of the C919 has been postponed repeatedly, it is necessary to know that the technological content of large passenger aircraft is extremely high. It is not a simple assembly machine. This is a historical step in China. As long as it can be done well, it can be tolerant in time.
According to expert analysis, compared with the Boeing 737 and Airbus A320, the C919 technology is more advanced. The four-sided windshield is the internationally leading design, with low aerodynamic drag, high strength requirements, complicated manufacturing process and high cost.
Quietly continue to look forward to it.
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