Tom Stafford's Concerns About Fueling Crewed Falcon 9

Letter From Tom Stafford to NASA Regarding Crewed SpaceX Falcon 9 Fueling Issues

"There is a unanimous, and strong, feeling by the committee that scheduling the crew to be on board Dragon spacecraft prior to loading oxidizer into the rocket is contrary to booster safety criteria that has beenin place for over 50 years, both in this country and internationally. Historically, neither the crew nor any other personnel have ever been allowed in or near the booster during fueling. Only after the booster is folly fueled and stabilized are the few essential people allowed near it. Furthermore, in addition to the personnel risk, there is the risk of operating the engines outside their design input conditions. As an experienced "Prop" guy you know the problem here as well as anyone. Pump-fed chemical engines require a sufficient and consistent input pressure to reduce the likelihood of cavitation or unsteady flow operations. We are concerned that there may be insufficient precooling of the tank and plumbing with the current planned oxidizer fill scenario, and without recirculation there may be stratification of oxidizer temperature that will cause a variation in the input conditions to the oxidizer pump."

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