SHERPA Commercial derivatives of the ESPA Grande ring include the Spaceflight Secondary Payload System (SSPS) and SHERPA developed and manufactured by Andrews Space under contract to Spaceflight Services. SSPS includes five -diameter ports, each capable of carrying payloads weighing up . "The SSPS operates very similar to a standalone spacecraft with a flight computer, electrical power system, orbit determination capability, and payload power switching." SHERPA is a powered variant of SSPS capable of large orbit change. LCROSS When NASA upgraded its Lunar Reconnaissance Orbiter (LRO) mission's launch vehicle to an Atlas V, it freed around 2,200 lbs. of additional mass for what would later become the Lunar Crater Observation and Sensing Satellite (LCROSS). NASA held a competition to see how best to use the space and a number of proposals came from the Ames Research Center. The winning proposal included Moog CSA Engineering's ESPA ring serving as the base mechanical satellite bus to launch the LCROSS spacecraft as a secondary payload under the LRO. LCROSS ultimately impacted the lunar surface and confirmed the presence of water ice. The LCROSS Lunar-impact water detection mission in 2009 took advantage of the structural capabilities of ESPA ring to attach all six of its science experiments, command and control systems, communications equipment, batteries, solar panels, and even a small monopropellant propulsion system to implement pre-impact payload separation and control. ESPAStar The ESPAStar is a comparable design concept by Orbital Sciences Corporation. Its maiden flight was on the AFSPC-11 mission as the EAGLE secondary payload. Long Duration Propulsive ESPA (LDPE) The LDPE (Long Duration Propulsive ESPA) is based on a Northrop Grumman payload adapter used to help attach the upper stage to the main satellite in addition to hosting a few slots for other smallsats. However, the entire system is powered by the ESPAStar satellite bus, which is in charge of power consumption and distribution as well as propulsion making it a fully operational space tug capable of deploying different payloads at different orbits. ESPAStar has the capability to host 6 smallsat payloads totaling 1,920 kg (4,230 lb). The system is also able to provide 400 meters per second of delta-V via a Hydrazine propulsion module. The first LDPE was launched on 7 December 2021 on an Atlas V rocket as part of the STP-3 mission. It carried the Ascent cubesat from the Air Force Research Laboratory that was used to test commercial off-the-shelf technologies