美国GE公司在GE90发动机的研制和取证过程中,就试图超出获取型号合格证的最低要求并达到最新制订的早期双发延程飞行(E-ETOPS)的要求,即在飞机和发动机取证和投入航线使用时就达到开辟ETOPS航线的能力。以前,民用运输机发动机在申请型号合格证时主要进行两项验证工作。首先要达到联邦航空条例FAR第33章规定的安全性水平,第二要有令人满意的“视情维修”的可靠性。 In the process of developing and certifying the GE90 engine, GE of the United States attempted to exceed the minimum requirements for obtaining model certification and reached the requirements of the newly developed E-ETOPS. That is, when aircraft and engine forensics and investment Route to use to achieve the ability to open ETOPS routes. In the past, civil transport aircraft engines apply for two types of certification when the main validation work. The first is the level of safety required by the FAR Chapter 33 of the FAR and the second is a satisfactory “dependable maintenance” reliability.