The 2011 NASA ~422,400 m3 Super Pressure Balloon Test Flight

Abstract

The National Aeronautics and Space Administration’s (NASA) Balloon Program Office recently completed a successful test flight of a large pumpkin shaped Super Pressure Balloon. This flight represents another incremental step toward offering the capability of extended duration stratospheric flights of large science instruments at mid latitudes with the goal of lifting a ton of science to greater than 33 km on a balloon that will fly at a near constant pressure altitude for extended periods. A ~532,200 m3 (18.8-MCF) pumpkin shaped Super Pressure Balloon test flight was launched from the Swedish Space Corporation’s Esrange Balloon Launch Facilities near Kiruna, Sweden on 14 August, 2012. This first test flight of a vehicle this size was a deployment verification test of this vehicle with a test flight gondola configured specifically for this mission. The goals of this test flight were to verify the balloon design through demonstration of balloon deployment and subsequent pressurization of the structure. The balloon ascent was just as predicted and performed flawlessly for the duration of the flight. The balloon fully deployed at a very low differential pressure of ~15 Pa, which was an outstanding demonstration of the design. The flight reached a float altitude of ~34 km (111,600 ft, GPS) with a suspended load of ~2,270 kg (~5,000 lbs). The total flight time was 6 hours 27 minutes. Ballast was dropped in increments to increase the differential pressure of the structure to explore the structures strength. All ballast on board was dropped resulting in a maximum pressure differential of ~160 Pa, or approximately 90% of the maximum design value. The balloon remained stable throughout the flight and maintained pressure during the entire flight. The flight was terminated by command in an area conducive to recovery. This flight was another success for this development program. The Super Pressure Balloon development project approach has focused on incremental steps up in balloon volume and payload carrying capability. This test flight successfully demonstrated balloon vehicle performance, obtained a large amount of video, measured differential pressure at the base of the balloon, measured the tension in a select number of tendons, obtained temperature and altitude data, and demonstrated the balloon vehicles altitude stability.