Table 2. List of trajectory contingencies and prioritization result (continued on the next page)

Phase Contingency Condition L C L × C Priority Complexity
Launch Launch time Off-nominal trajectory 2 3 6 3 Low
Low C3 energy Earth return 2 4 8 2 Medium
High C3 energy Heliocentric escape 1 4 4 3 Medium
RAV error Off-nominal trajectory 2 3 6 3 Low
DAV error Off-nominal trajectory 2 3 6 3 Low
Col. avoidance High probability conjunction 1 4 4 3 Medium
Planning TCM Over budget Fail to achieve mission orbit requirements 2 3 6 3 Medium
TCM3 No burn Fail to approach Moon 3 4 12 2 Medium
Partial burn Off-nominal trajectory 3 1 3 3 Low
Over burn Off-nominal trajectory 2 1 2 3 Low
Delayed start Off-nominal trajectory 2 1 2 3 Low
Early start Off-nominal trajectory 2 1 2 3 Low
Az. pointing error Off-nominal trajectory 2 1 2 3 Low
El. pointing error Off-nominal trajectory 2 1 2 3 Low
TCMX No burn Off-nominal trajectory 2 3 6 3 Medium
Partial burn Off-nominal trajectory 3 2 6 3 Low
Over burn Off-nominal trajectory 3 2 6 3 Low
Delayed start Off-nominal trajectory 2 1 2 3 Low
Early start Off-nominal trajectory 2 1 2 3 Low
Az. pointing error Off-nominal trajectory 2 1 2 3 Low
El. pointing error Off-nominal trajectory 2 1 2 3 Low
Planning LOI LOI Epoch error Off-nominal trajectory 3 3 9 2 Medium
LOI altitude error Off-nominal altitude 3 3 9 2 Medium
LOI inclination error Off-nominal inclination 3 3 9 2 Medium
Over budget Fail to achieve mission orbit requirements 2 3 6 3 Medium
Col. avoidance High probability conjunction 1 5 5 3 Medium
LOI1 No burn Fail to capture 3 5 15 1 High
Partial burn Fail to capture 4 5 20 1 High
Partial burn Off-nominal orbit, T > 12 h 4 4 16 1 Medium
Over burn Off-nominal orbit, T < 12 h 1 1 1 3 Low
Delayed start Off-nominal orbit 2 2 4 3 Low
Early start Off-nominal orbit 2 2 4 3 Low
Az. pointing error Off-nominal inclination 2 4 8 2 Medium
El. pointing error Off-nominal orbit 2 1 2 3 Low
LOI2 No burn Remain in 12 h orbit 3 4 12 2 Low
Partial burn Off-nominal orbit, T > 5.75 h 4 3 12 2 Low
Over burn Off-nominal orbit, T < 5.75 h 1 1 1 3 Low
Delayed start Off-nominal orbit 2 1 2 3 Low
Early start Off-nominal orbit 2 1 2 3 Low
Az. pointing error Off-nominal inclination 2 4 8 2 Medium
El. pointing error Off-nominal orbit 2 1 2 3 Low
LOI3 No burn Remain in 5.75 h orbit 2 4 8 2 Low
Partial burn Off-nominal orbit, T > 3.60 h 3 3 9 2 Low
Over burn Off-nominal orbit T < 3.60 h 1 1 1 3 Low
Delayed start Off-nominal orbit 2 1 2 3 Low
Early start Off-nominal orbit 2 1 2 3 Low
Az. pointing error Off-nominal inclination 2 4 8 2 Medium
El. pointing error Off-nominal orbit 2 1 2 3 Low
LOI4 No burn Remain in 3.60 h orbit 2 4 8 2 Low
Partial burn Off-nominal orbit, T > 2.58 h 3 3 9 2 Low
Over burn Off-nominal orbit T < 2.58 h 1 1 1 3 Low
Delayed start Off-nominal orbit 2 1 2 3 Low
Early start Off-nominal orbit 2 1 2 3 Low
Az. pointing error Off-nominal inclination 2 4 8 2 Medium
El. pointing error Off-nominal orbit 2 1 2 3 Low
LOI5 No burn Remain in 2.58 h orbit 2 4 8 2 Low
Partial burn Off-nominal orbit, T > 1.99 h 3 3 9 2 Low
Over burn Off-nominal orbit, T < 1.99 h 1 1 1 3 Low
Delayed start Off-nominal orbit 2 1 2 3 Low
Early start Off-nominal orbit 2 1 2 3 Low
Az. pointing error Off-nominal inclination 2 4 8 2 Medium
El. pointing error Off-nominal orbit 2 1 2 3 Low
OTM1 No burn Off-nominal orbit 2 1 2 3 Low
Partial burn Off-nominal orbit 2 1 2 3 Low
Over burn Off-nominal orbit 1 1 1 3 Low
Delayed start Off-nominal orbit 1 1 1 3 Low
Early start Off-nominal orbit 1 1 1 3 Low
Az. pointing error Off-nominal inclination 2 1 2 3 Low
El. pointing error Off-nominal orbit 2 1 2 3 Low
OTM2 No burn Off-nominal orbit 2 1 2 3 Low
Partial burn Off-nominal orbit 2 1 2 3 Low
Over burn Off-nominal orbit 1 1 1 3 Low
Delayed start Off-nominal orbit 1 1 1 3 Low
Early start Off-nominal orbit 1 1 1 3 Low
Az. pointing error Off-nominal inclination 2 1 2 3 Low
El. pointing error Off-nominal orbit 2 1 2 3 Low
OMM No burn Off-nominal orbit 2 1 2 3 Low
Partial burn Off-nominal orbit 2 1 2 3 Low
Over burn Off-nominal orbit 1 1 1 3 Low
Delayed start Off-nominal orbit 1 1 1 3 Low
Early start Off-nominal orbit 1 1 1 3 Low
Az. pointing error Off-nominal inclination 2 1 2 3 Low
El. pointing error Off-nominal orbit 2 1 2 3 Low
L, likelihood; C, consequence; TCM, trajectory correction maneuver; LOI, lunar orbit insertion; OTM, orbit trim maneuver; OMM, orbit maintenance maneuver; C3, launch injection energy per unit mass; RAV, right ascension of the injection orbit apoapsis vector; DAV, declination of the injection orbit apoapsis vector; Col, collision; Az, azimuth; El, elevation.