SWIFT burst alert telescope loop heat pipe thermal system characteristics and flight operation procedure

Loop heat pipe (LHP) startup procedure is required after the spacecraft checkout phase, which follows the launch, ascent and early orbit phase, and after a safehold mode. This procedure will be verified during the BAT (burst alert telescope) instrument thermal vacuum and thermal balance test. The startup procedure and the LHP components in the normal flight operation mode are discussed in detail. The BAT power convertor box is used to contain power switches for the TCS normal operation mode heaters. It is required to supply voltage to the electronic heater controllers to power heaters, and adjustable voltage signals to the heater controllers to change the temperature set points in flights. It is also required to supply voltage to the startup heaters of the LHP.