Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

ConstraintDescription
WA,H > WA,E,F,G + RD + SD + lfcWhen lines between the mission package and fin can are fully extended, the drogue parachute must be within the airstream.
WA,E,F = lmpPlacing the junction between the tender descender (TD) and the main chute load paths at the edge of the mission package reduces the likelihood that the main parachute will enter the airstream prior to the designated release altitude of 2,000 ft.
WC,D > RBThe line connecting the top of the main chute canopy to the inside of the deployment bag must be long enough such that the main parachute is not stuck inside the deployment bag upon full line extension.
WA,B > lmp + ~4DMAs a temporary value, the main parachute must be at least 5 diameters away from the mission package when inflated. This constraint also ensures that it is outside of the mission package, assuming full line extension. Further analysis will be performed to refine this constraint.
WA,E,F,G - lmp > 5DD

This constraint reduces the impact of forebody wake on the drogue parachute during drogue descent.

WA,H > lmp + hmp + lfcAssuming full line extension, the mission package and booster section should not hit one another during descent. This neglects the effect of drag on these sections and their respective masses.
WA,E,F < WA,B + SM + RM + WC,D,FPrior to firing the tender descender, the load should go through the shorter (TD) path.

  

Webbing lengths were calculated using the constraints with the addition of reasonable factors of safety.

Webbing Length VariableLength (in)Factor of SafetyReasoning
WA,H295.44The absolute minimum factor of safety required for the constraints is a little above 3.6 so that was rounded up to 4.
WA,E,F,G189.81The 5DD in the constraint equation was determined arbitrarily so the factor of safety is redundant.
WA,B473.81The 4DM in the constraint equation was determined arbitrarily so the factor of safety is redundant.
WA,E,F17.81A factor of safety is not desirable here because the exact length is desired.
WC,D27010In subsonic flow, upstream disturbances could disrupt the airflow using minimal length on this webbing.
WC,D,F121There's no clear constraint on this length, so an arbitrary small length was chosen.