Johnson Space Center’s (JSC) GIII provides a reliable, configurable, and comfortable airborne platform to the earth science community and other customers in order to support scientific research and advanced technology development and testing worldwide. The aircraft supports the NASA Airborne Science Program. Prior to the purchase of the GV, the primary mission of the GIII (N992NA) was to transport astronauts returning from Kazakhstan to Houston, Texas after completing missions aboard the International Space Station. Currently, it serves as a backup aircraft to the GV for the direct return mission. In 2011-2012, the aircraft was extensively modified to accommodate the NASA Jet Propulsion Laboratory's Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) instruments in a pod below the fuselage. The interior was also modified to include equipment racks and crew stations for the UAVSAR and Platform Precision Autopilot (PPA) operators. The G-III has successfully flown all three radar frequencies in support of numerous NASA science objectives including two major Earth Venture program, Airborne Microwave Observatory of Subcanopy and Subsurface (AirMOSS) and Oceans Melting Greenland (OMG). In addition a sonobuoy launch system was installed on the aircraft in 2016 to support launching sonobuoys for OMG.
The aircraft can be modified to meet customer needs. The cabin can be configured with standard 19” equipment racks and operator consoles as required. The maximum weight per rack is 300 lbs. Up to 15 mission crew/passengers can be accommodated depending on internal cabin configuration. An external pod for radar, lidar, or other instrumentation is available, mounted on a MAU-12C/A external store rack. Maximum pod weight is currently 1,200 lbs. Up to ten kilowatts of combined 28 VDC/115 VAC (60 Hz or 400 Hz) electrical power is available for experimenters.
The JSC GIII has flown nearly 2,000 operational flight hours in support of the Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) for a multitude of science objectives and is capable and has flown all three radars, P-band, L-band, and Ka-band. The aircraft successfully completed the Earth Venture 1 AirMOSS mission and is participating in the Earth Venture Suborbital 2 (EVS-2) mission Oceans Melting Greenland (OMG). Additional science objectives have included mapping landslides, measuring faults, imaging levees, and mapping volcano flows.
In 2016, JSC completed the in-house design, analysis, and modification of the G-III to launch AXCTD sonobuoys from the aircraft to support the EVS-2 mission OMG. JSC finished the first OMG deployment successfully launching 213 sonobuoys into the coastal waters and fjords circumnavigating Greenland.
The GIII was built by Gulfstream Aerospace Corporation in Savannah, Georgia in 1981 as model number G-1159A, serial number 309. During the 1980s, it was primarily flown as a corporate jet. In 1989, it began service with NASA as N1NA, flying missions in support of NASA Headquarters and Langley Research Center, Virginia. In 2006, the aircraft was transferred to Johnson Space Center and re-registered as N2NA, serving as a mission management aircraft. After one year's service at NASA Dryden Flight Research Center, California as N803NA during 2008-2009, the aircraft was returned to Johnson Space Center in late 2009 and re-registered as N992NA. It is currently stationed at Ellington Field, Houston, Texas.