1. LVpayload Step1a 25,694 25,694 3rd-stageweightratio Step2c 6.5 6 stage-3gross weight (1*2) 167,011 154,164 2ndstageweightratio Step2c 3.75 3.6 stage-2gross weight (3*4) 626,291.25 554,990.4 1ststageweight ratio Step2c 2.82 2.82 launchvehiclegross weight (5*6) 1,766,141.325 1,565,072.928 Stage1 weight (7-5) 1,139,850.075 1,010,082.528 Stage2 weight (5-3) 459,280.25 400,826.4
2. Stage3 weight (3-1) 141,317.0 128,470.0 e STRUCTUREFACTORCOMPARISON Iter.1 Iter.2 Iter.3
3. Thepresent studyis, therefore,not presentinga strict tool validation effort. Theresearch team decidedinsteadto explore if the legacy X-20 Dyna-Soar hardware system would be capable to serve a modern ISS mission. This experimentisofparticular interesttodaysincetheutilization oftheSpace PlannersGuide enablestheresearch team todayto use a `consistent' estimation capability compared to the 1960s, assuming that the original X-20 Dyna-Soar design has been largely `locked in' by using the sizing mentality and proficiency demonstrated with the 1965- available Space PlannersGuide. Withthisperspectivein mind, the`validation results'presentedhereareacceptable within a reasonablemargin of error. Having said such, Table12 presentsthemission-hardwarecomparison between the legacyX-20 Dyna-Soar and hardware sizingresults obtained using the Space Planners Guide, knowing that the underlying designmissionsdeviatessomeasdescribed.
4. When comparing the Space Planners Guide sizing results with the legacy X-20 Dyna-Soar source data, it is obvious that the Space Planners Guide results are mostly within the ten percent error margin. As discussed above, the important assumption here is that the two missions (1960s and 2014) are slightly different since the original 1960sreferencemission has been defined for a shorter duration andlower altitude.Thisclearlyaffectstheweight of theX-20transition section sincetheauxiliaryunitsarerequired toperformfor longer in-spacetimeperiod.