任何材料在用于飞机结构之前,均需经过多次的试验。因为飞机经常遭受巨大的温度变化,如地面温度可达到-40℃以下,在空中可达到-70℃以上,甚至-90℃。此外,在热带飞机库中的飞机是封闭的,发动机就像一个热幅射器一样,空气的温度可达到100℃。飞机在低空时会由于飞鸟而遭到损伤。另一个重要 Any material used in the aircraft structure, are subject to repeated tests. Because the aircraft often suffer huge temperature changes, such as the ground temperature can reach below -40 ℃, up to -70 ℃ in the air, or even -90 ℃. In addition, the aircraft in the tropical hangar is closed and the engine behaves like a hot radiator with air temperatures up to 100 ° C. The aircraft was damaged by the birds at low altitude. Another important one