前言 1993年作者复查事故报告时,注意到美国军事安全中心(USASC)官员对空间失定向(SD)旋翼机事故率的估计,与实际包括空间失定向的程度之间,存在着差别。 方法为了追踪调查,Murdock等分析了1987～1992年间被USASC列为涉及SD的A～c类的旋翼机事故中SD所起的作用。同时,Durnford等人重新审查了所有A～C类事故报告,以重新确定sD Preface In 1993, when the author reviewed the accident report, he noticed that there was a difference between the estimates by the US Military Security Center (USASC) officials on the rate of accidental loss of spacecraft rotorcraft (SD) and the actual extent of misalignment in space. Methods In order to follow up the investigation, Murdock et al. Analyzed the role of SD in the rotorcraft accidents of 1987 to 1992 that were classified by the USASC as Category A ~ C involving SD. In the meantime, Durnford et al. Reviewed all A-C incident reports to re-determine sD