您即将离开哈喽比特，请留意您所访问的内容是否安全。
https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgSAIB.nsf/dc7bd4f27e5f107486257221005f069d/27ffcbb45e6157e9862587810044ad19/%24FILE/AIR-21-18.pdf
