Preliminary Flight Sequence
The first stage, along with its solid rocket motors, lift the vehicle out of the Earth’s lower atmosphere. The second stage steers the SMAP spacecraft into the correct orbit using its onboard guidance system. The fairing protects the spacecraft from heating and large aerodynamic forces experienced during 1st stage ascent. Once the 2nd stage is out of the atmosphere, this protective fairing is jettisoned after it is no longer needed. Following separation, the spacecraft deploys its solar array, orients itself to point the array at the Sun, then establishes radio contact with both ground stations and TDRS satellites to relay telemetry data on spacecraft health back to the SMAP Mission Operations Center (MOC) at JPL.