STP-2

STP-2 carries multiple cubesats and other small payloads for NASA, NOAA, The Planetary Society and others in addition to the primary mission which consists of multiple U. S. Air Force payloads.

USAF Space Test Program Flight 2 (STP-2) carried 24 small satellites, including: FormoSat-7 A/B/C/D/E/F integrated using EELV Secondary Payload Adapter, DSX, Prox-1 GPIM, DSAC, ISAT, SET, COSMIC-2, Oculus-ASR, OBT, NPSat, and several CubeSats including E-TBEx, LightSail 2, TEPCE, PSAT, and three ELaNa 15 CubeSats. Total payload mass was 3,700 kg (8,200 lb). The mission lasted six hours during which the second stage ignited four times and went into different orbits to deploy satellites including a "propulsive passivation maneuver". Third flight of Falcon Heavy. The side boosters from the Arabsat-6A mission just 2.5 months before were reused on this flight and successfully returned to LZ-1 and LZ-2. The center core, in use for the first time, underwent the most energetic reentry attempted by SpaceX, and attempted a landing over 1,200 km (750 mi) downrange, 30% further than any previous landing. This core suffered a thrust vector control failure in the center engine caused by a breach in the engine bay due to the extreme heat. The core thus failed its landing attempt on the drone ship Of Course I Still Love You due to lack of control when the outer engines shut down. For the first time, one fairing half was successfully landed on the catch-net of the support ship GO Ms. Tree (formerly Mr. Steven).