Work breakdown Structure Space System Launch Vehicle Space Vehicle Ground Command Control Communications and Mission Equipment Payload Spacecraft Reentry vehicle Integration, Assembly Test and Checkout5 Work Breakdown Structure Launch Vehi cle P a yload Spa c e craft Re e ntry v e hicl e Inte gration, A s s e m bly, T est a n d Ch ecko ut Spa c e Vehi cle Gr o und C o m m and, Co ntrol, Co m m u nicati o n s an d Mis sion E q uip ment S pace S y stem