美国为“大力神”研制新的喷管裙部在最近一次导致推迟发射的地面试验失败后，美空军和航空喷气发动机公司决定加快研制后继型“大力神”４第二级的喷管裙部。地面试验包括鉴定石棉酚醛裙部所用的新材料。此裙部连于发动机喷管底部以获取最佳性能。它通过改变喷管的扩张比... U.S. Develops New Nozzle Skirt for Hercules Following a recent ground test that led to a late launch, the U.S. air force and jet engine company decided to expedite the development of a subsequent “Hercules” 4 second-stage nozzle skirt . Ground tests include the identification of new materials used in asbestos phenolic skirts. This skirt is attached to the bottom of the engine nozzle for best performance. It is by changing the nozzle expansion than ...