Section 431.35 - [Effective until 3/10/2026] Acceptable reusable launch vehicle mission risk(a) To obtain safety approval for an RLV mission, an applicant must demonstrate that the proposed mission does not exceed acceptable risk as defined in this subpart. For purposes of this section, the mission commences upon initiation of the launch phase of flight and consists of launch flight through orbital insertion of an RLV or vehicle stage or flight to outer space, whichever is applicable, and reentry or descent flight, and concludes upon landing on Earth of the RLV.(b) Acceptable risk for a proposed mission is measured in terms of the expected average number of casualties (Ec).(1) To obtain safety approval, an applicant must demonstrate the following for public risk: (i) The risk to the collective members of the public from the proposed launch meets the public risk criteria of § 417.107(b)(1) of this chapter;(ii) The risk level to the collective members of the public, excluding persons in water-borne vessels and aircraft, from each proposed reentry does not exceed an expected number of 1 * 10-4 casualties from impacting inert and explosive debris and toxic release associated with the reentry; and(iii) The risk level to an individual does not exceed 1 * 10-6 probability of casualty per mission.(c) To demonstrate compliance with acceptable risk criteria in this section, an applicant shall employ a system safety process to identify the hazards and assess the risks to public health and safety and the safety of property associated with the mission, including nominal and non-nominal operation and flight of the vehicle and payload, if any. An acceptable system safety analysis identifies and assesses the probability and consequences of any reasonably foreseeable hazardous event, and safety-critical system failures during launch flight or reentry that could result in a casualty to the public.(d) As part of the demonstration required under paragraph (c) of this section, an applicant must- (1) Identify and describe the structure of the RLV, including physical dimensions and weight;(2) Identify and describe any hazardous materials, including radioactive materials, and their container on the RLV;(3) Identify and describe safety-critical systems;(4) Identify and describe all safety-critical failure modes and their consequences;(5) Provide drawings and schematics for eachsafety-critical system identified under paragraph (d)(3) of this section;(6) Provide a timeline identifying all safety-critical events;(7) Provide data that verifies the risk elimination and mitigation measures resulting from the applicant's system safety analyses required by paragraph (c) of this section; and(8) Provide flight trajectory analyses covering launch or ascent of the vehicle through orbital insertion and reentry or descent of the vehicle through landing, including its three-sigma dispersion.Doc. No. FAA-1999-5535, 65 FR 56658 , Sept. 19, 2000, as amended by Amdt. 431-2, 72 FR 17019 , Apr. 6, 2007; Docket No. FAA-2014-0418, Amdt. No. 431-4, 81 FR 47027 , July 20, 2016