HIPO in-flight performance aboard SOFIA

HIPO is a special purpose science instrument for SOFIA that was also designed to be used for Observatory test work. It was used in a series of flights from June to December 2011 as part of the SOFIA Characterization and Integration (SCAI) flight test program. Partial commissioning of HIPO and the co-mounted HIPO-FLITECAM (FLIPO) configuration were included within the scope of the SCAI work. The commissioning measurements included such things as optical throughput, image size and shape as a function of wavelength and exposure time, image motion assessment over a wide frequency range, scintillation noise, photometric stability assessment, twilight sky brightness, cosmic ray rate as a function of altitude, telescope pointing control, secondary mirror control, and GPS time and position performance. As part of this work we successfully observed a stellar occultation by Pluto, our first SOFIA science data. We report here on the observed in-flight performance of HIPO both when mounted alone and when used in the FLIPO configuration.