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Despite the fact that the performance of organic solar cells is generally susceptible to degradation by moisture exposure, there has been suggestion that the photoactive layer (P3HT) is surprisingly resilient. This work attempts to confirm the stability of P3HT as an organic solar cell material by deliberately introducing water into the photoactive layer. A dramatic step drop in device performance during cell characterization is observed approximately one day after the device has been fabricated. The time-delayed step drop in output efficiency strongly suggests that moisture has little effect on the P3HT conducting polymer.

An automated Fourier Transform Spectroscopic (FTS) solar observatory was established in Darwin, Australia in August 2005. The laboratory is part of the Total Carbon Column Observing Network, and measures atmospheric column abundances of CO2 and O2 and other gases. Measured CO2 columns were calibrated against integrated aircraft profiles obtained during the TWP-ICE campaign in January– February 2006, and show good agreement with calibrations for a similar instrument in Park Falls, Wisconsin. A clearsky low airmass relative precision of 0.1% is demonstrated in the CO2 and O2 retrieved column-averaged volume mixing ratios. The 1% negative bias in the FTS XCO2 relative to theWorld Meteorological Organization (WMO) calibrated in situ scale is within the uncertainties of the NIR spectroscopy and analysis.

The XV-11A is a polyester reinforced fiber glass STOL aircraft. This four-place aircraft, powered by a 250-horsepower T-63 turbine engine, was designed to achieve high-lift coefficients by means of a variable camber wing with distributed suction boundary layer control. A shrouded propeller was used for thrust augmentation at low forward velocities, and beta control on the propeller was successfully used as a drag increment for glide path control. To date, the XV-11A aircraft has flown 49 flights with a total flight time of 35 hours. The majority of the flight time was involved in aerodynamic research of the shrouded propeller, the distributed suction boundary layer control system and in an evaluation of the general handling characteristics of the aircraft. A minimum of performance data was collected since the primary objective was aerodynamic research. The fiber glass material demonstrated the excellent possibilities of this type of construction when complex, aerodynamically smooth curvatures are desired.

An interim test-bed aircraft, the Marvelette, was built to evaluate functionally the compati bility of the various features of the Marvel design (boundary-layer control, cambered wing, ducted propeller, fiberglass structure). Also, the Marvelette, designated XAZ-1, will provide information for the refinement of the Marvel de sign and be a readily available laboratory for exploration of low-speed aerodynamics in flight. Pilot evaluation and flight data on the Marvel ette are presented for the first ten aircraft checkout flights. (Author)