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Stephanie Morris 2/21/08 Propulsion Standard Deviations. Propulsion Standard Deviations. Using the standard deviation values from the Vanguard report, the standard deviations for the propellant mass of our launch vehicle were estimated. Assumptions: Launch vehicle of LG-CA-DA-DT.
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Stephanie Morris2/21/08PropulsionStandard Deviations AAE 450 Spring 2008
Propulsion Standard Deviations Using the standard deviation values from the Vanguard report, the standard deviations for the propellant mass of our launch vehicle were estimated. • Assumptions: • Launch vehicle of LG-CA-DA-DT. • Current launch vehicle output values for propellant mass and mass flow rates are accurate. • Percent standard deviation can be used to compute standard deviations for our LV. AAE 450 Spring 2008 Propulsion
Propulsion Standard Deviations • Future Work: • Check standard deviation against other launch vehicles. AAE 450 Spring 2008 Propulsion
References Burkhardt, H., Herbertz, A., Sippel, M., Klevanski, J. “Solid Propellant Hypersonic X-Vehicle Options as RLV Technology Stepping Stones”. Space Launcher Systems Analysis. 2002. Isakowitz, Steven J., Hopkins, Joshua B., Hopkins, Joshua P Jr. International Reference Guide to Space Launch Systems. Fourth Edition. AIAA, Reston, VA 2004 Martin Company, The Vanguard Satellite Launching Vehicle, Engineering Report No.11022. April 1960, pp. 26, 208 AAE 450 Spring 2008 Propulsion
Historical Data for Comparison AAE 450 Spring 2008
Section of Final Report In order to compute the accuracy using the “Monte Carlo” method, the propulsion standard deviations of mass flow rate and propellant mass must be calculated. Using values from the Vanguard report for the standard deviation and average value, the percent deviation was computed using Equation (1). % Deviation = Standard Deviation / Average Value Eq.(1) Once the percent deviation was obtained, the value for propellant mass and mass flow rate, at each stage, was used to calculate the standard deviation for our launch vehicle. For example, Standard Deviation = % Deviation * Propellant Mass Eq.(2) Using the output values of propellant mass and mass flow rates, the standard deviation was calculated. For total propellant mass the standard deviation is 15.9. The standard deviation for mass flow rate of the first stage is 0.0885 and the second stage is 0.0265. AAE 450 Spring 2008