In which phase does the thermally initiated venting system (TIVS) operate?

The thermally initiated venting system (TIVS) is designed to operate during the post-launch phase of a spacecraft or missile system. This system plays a crucial role in controlling and managing any excess pressure that may build up in the vehicle after it has launched. After the initial propulsion phase, when the vehicle is in flight, the TIVS can safely vent gases that could be generated due to the heat and other conditions experienced during this phase.

During the post-launch phase, the focus shifts from just achieving lift-off to stabilizing the spacecraft’s environment. The TIVS ensures that any thermal-induced pressures do not compromise the integrity of the vehicle. It is this careful management of pressure that helps to maintain the safe operation of the system, contributing to the overall success of the mission.

In contrast, the other phases mentioned—launch, pre-flight, and mid-course—do not involve the pressures or thermal conditions suitable for the TIVS to engage effectively, as their operational requirements differ significantly during those stages.