Does SOFIA require a crew escape system?

National Aeronautics and Space Administration (NASA) and Deutsches Zentrum fur Luft- und Raumfahrt (DLR) have been working together to create the Stratospheric Observatory For Infrared Astronomy (SOFIA). The design and modifications have progressed to the point that SOFIA begins its development-phase flight tests in 2006. This paper shows the rationale for the SOFIA program´s decision to not require a crew escape system during the development-phase flight tests. The dominant risk during the flight test phase is stall testing that has to be performed to meet NASA airworthiness and Federal Aviation Administration (FAA) certification requirements. The assessment showed that under a loss of control/loss of aircraft scenario during a stall test, the aircraft is unlikely to remain stable enough to allow existing crew escape systems to be effective. Similar examination of all other major risks showed that, apart from fire risks, potential crew escape systems are unlikely to be effective. Fire risks have been adequately mitigated by other means. In summary, current qualitative and quantitative safety analyses provided support for SOFIA´S program position that SOFIA does not require a crew escape capability during the development-phase flight tests