NASA will roll out their first fully stacked Space Launch System (SLS) rocket to LC-39B, where it will complete a wet dress rehearsal (WDR) which involves loading the vehicle with propellants and taking the vehicle through the countdown to ignition where the countdown is halted. After the WDR, NASA will roll the vehicle back to the Vehicle Assembly Building to complete final checks prior to rolling out for launch later this year. The rollout is expected to take around 11 hours, and will utilise an upgraded crawler transporter - the same system its predecessors (Space Shuttle, Ares, Saturn, etc.) used.