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NB: «Applicable» means that the criteria is checked by the software
When using the statistical mode, the termination criteria and "Protected LEO & GEO Regions" criteria
applicability depends on initial/nominal orbit parameters as well. The following table summarizes the
conditions of use for these criteria in STELA software.
GTO Statistical Mode
Termination
criterion STC1
Termination
criterion STC2
Termination
criterion STC3
Applicable
Applicable when automatic stop is selected
Applicable
Applicable if the nominal (non dispersed) orbit
belongs to protected LEO region
Applicable if the nominal (non dispersed) orbit
SC2 criterion
does not belong to protected LEO region
SC3 criterion
Applicable
SC4 criterion
Applicable
SC1 criterion
4.4. Protected regions criteria status
At the end of the simulation the STELA software checks the compliance with the four "Protected LEO &
GEO Regions" criteria. Five status are possible, and depend on initial parameters and simulation results.
"Not applicable" : this status is written in the output results when the current "Protected Region"
criterion is not applicable (report to §4.3),
"Not computable" : this status is written in the output results when the current "Protected Region"
criterion is fulfilled during the simulation duration, but when the simulation duration is too short to
allow any conclusion, or when the number of simulations is too short for a statistical analysis, or when
the statistical analysis was not conclusive (report to § 4.2.9 ).
"Not compliant" : this status is written in the output results in the output results when the current
"Protected Region" criterion is not fulfilled.
"Compliant" : this status is written in the output results when the current "Protected Region" criterion is
fulfilled during the simulation duration, and when the simulation duration is long enough.
"Not Reliable" : this status replaces both "Compliant" and "Not Compliant" status for a GTO
simulation. It indicates that one single orbit propagation can not give a reliable criterion status due to
resonance phenomena (see § 3.9.2 and Warning 2).
Warning 1 : the simulation duration must be:
at least 25 years in order to allow the STELA software to ensure in any case the compliance with C1
and C2 criteria,
at least 100 years in order to allow the STELA software to ensure in any case the compliance with C2,
SC2, C3, SC3, C4 and SC4 criteria.
Warning 2 : for GTO orbits the extrapolation results are very sensitive to the initial conditions (date, perigee
position wrt the sun direction...) and to the computation parameters (area, drag and SRP coefficients, solar