Altair unmanned aircraft system achieves demonstration goals

Abstract

In the early morning of 15 November 2005, the unmanned Altair aircraft returned to Gray Butte Airfield, north of Los Angeles, Calif., after completing an 18.4‐hour mission over the eastern Pacific Ocean. The flight was the last in a series undertaken by the U.S. National Oceanic and Atmospheric Administration (NOAA) in its Unmanned Aircraft System (UAS) Demonstration Project. The successful flight series has helped start the era of unmanned flights in service of environmental goals. Altair cruised at altitudes in the lower stratosphere (13 kilo‐meters; ∼43,000 feet), collecting atmospheric data with a 140‐kilogram payload of both remote and in situ instruments.

Tropospheric SF6: Age of air from the Northern Hemisphere midlatitude surface

“…; Fahey et al . ; Wofsy , ] instruments, and measurements from flasks collected with an onboard NOAA whole air sampler (NWAS) were analyzed by the CCGG. (Additional whole air samples were also taken by the University of Miami but are not included here.…”

Evaluation of the Airborne Quantum Cascade Laser Spectrometer (QCLS) measurements of the carbon and greenhouse gas suite – CO<sub>2</sub>, CH<sub>4</sub>, N<sub>2</sub>O, and CO – during the CalNex and HIPPO campaigns

“…Optical-based measurements are particularly sensitive to fluctuations in temperature and pressure (Zahniser et al, 1995) and careful controls must be implemented, particularly during flight where large dynamic ranges in both variables are observed (Fried et al, 2009). In-flight calibrations at regular intervals from gas cylinders are used to track sensor drift.…”

“…10, shows a bias of 1.8 ppb over the HIPPO mission. Moore et al, 2003;Fahey et al, 2006;Wofsy et al, 2011) and the PAN and other Trace Hydrohalocarbon ExpeRiment (PANTHER; Elkins et al, 2002;Wofsy et al, 2011) -measured a variety of chemical species including CH 4 , N 2 O, and CO. Figure 11 shows the one-to-one comparison of the QCLS to PANTHER (top) and UCATS (bottom) after applying the averaging kernel of each gas chromatograph (GC) to the 1 Hz QCLS data.…”

“…Growing interest in understanding the drivers of climate change has sparked innovation in instrumentation to measure long-lived greenhouse gases and associated chemical tracers (Chen et al, 2010;Fried et al, 2009;Nelson et al, 2004;O'Shea et al, 2013;Xiang et al, 2013a;Zahniser et al, 2009;Zare et al, 2009). The improvements in measurement precision and ease of use must be matched with a corresponding increase in calibration efforts to achieve comparable gains in compatibility.…”

Evaluation of the airborne quantum cascade laser spectrometer (QCLS) measurements of the carbon and greenhouse gas suite – CO<sub>2</sub>, CH<sub>4</sub>, N<sub>2</sub>O, and CO – during the CalNex and HIPPO campaigns

“…10, shows a bias of 1.8 ppb over the HIPPO mission. Two onboard gas chromatographs -the Unmanned Aircraft Systems (UAS) Chromatograph for Atmospheric Trace Species (UCATS, Moore et al, 2003;Fahey et al, 2006;Wofsy et al, 2011) and the PAN and other Trace Hydrohalocarbon ExpeRiment (PANTHER; Elkins et al, 2002;Wofsy et al, 2011) -measured a variety of chemical species including CH 4 , N 2 O, and CO. Figure 11 shows the one-to-one comparison of the QCLS to PANTHER (top) and UCATS (bottom) after applying the averaging kernel of each gas chromatograph (GC) to the 1 Hz QCLS data. In addition to the in situ data, sparser flask measurements from the NOAA Whole Air Sampler (NWAS) are compared in Fig.…”