DynaSoar
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I'll start.
Recently I've heard someone say that most rocketry speed/altitude flight profile calculators were "flat plate" estimates, meaning they pretty much just took frontal area into account (as well as weight, of course).
This seems to work fairly well, or at least fairly consistently. I've gotten results from Rocksim, SpaceCAD and Scott Ghiz's calculator that were all but indentical. But, as Scott Ghiz himself says, there's a lot of other factors involved, they just tend to balance each other out. Fine and well, but I need more.
For instance (and it was part of the discussion which prompted this) length matters. The more surface, the more turbulence, the more drag. How does this affect that number we're told is 0.75, the CD (coefficient of drag)? And I guess that what this comes to: what and the major factors that come into play for CD? What can we measure, or at least estimate, to convince ourselves that 0.75 CD actually applies?
Recently I've heard someone say that most rocketry speed/altitude flight profile calculators were "flat plate" estimates, meaning they pretty much just took frontal area into account (as well as weight, of course).
This seems to work fairly well, or at least fairly consistently. I've gotten results from Rocksim, SpaceCAD and Scott Ghiz's calculator that were all but indentical. But, as Scott Ghiz himself says, there's a lot of other factors involved, they just tend to balance each other out. Fine and well, but I need more.
For instance (and it was part of the discussion which prompted this) length matters. The more surface, the more turbulence, the more drag. How does this affect that number we're told is 0.75, the CD (coefficient of drag)? And I guess that what this comes to: what and the major factors that come into play for CD? What can we measure, or at least estimate, to convince ourselves that 0.75 CD actually applies?