GOES-16 ON-STATION CUSTOM MANEUVER GENERATION WITH FOCUSSUITE

This paper discusses the process of the NOAA GOES Mission Operations Support Team (MOST) in mitigating the effects of inconsistently-performing ArcJet Thrusters (AJTs) aboard the GOES-16 spacecraft in geostationary orbit. These AJTs are hot-gas thrusters which augment the gas flow using an electric arc to increase the exit velocity of the gases. Fuel flow problems have led to GOES-16 being unable to safely use its AJTs for maneuvers at times. This primarily affects North/South Station-Keeping (NSSK) maneuvers, which control inclination and use a majority of the station-keeping fuel budget. As a result, GOES-16 has had to occasionally resort to using non-AJT hot-gas thrusters. These thrusters are not placed as close to GOES-16's centerline, have lower thrust, and have lower specific impulse when compared to AJTs. In addition, MOST’s ground systems do not officially support using these non-AJT thrusters for NSSK maneuvers. MOST had to quickly develop workaround solutions using the FocusSuite Autofocus programming environment to compute the maneuvers. This paper outlines the mixture of commercial off-the-shelf (COTS) and MOST-developed products which have allowed GOES-16 to continue station-keeping even with inconsistently-performing AJTs, showing that script-based automation systems like Autofocus can simplify complex solutions to a few scripted user inputs.