Aircraft measurements of air-sea fluxes and boundary-layer structure were made during the Summer 2001 Rough Evaporation Duct (RED) experiment. They were obtained by the NPS/CIRPAS Twin Otter aircraft which was instrumented with wind , temperature, humidity, IR sea surface temperature and aircraft motion and navigation sensors. Data were recorded at up to 40 Hz rate for turbulent eddy correlation flux calculations. Twelve research flights, up to 5 hours duration, were flown East of Oahu mostly under moderate trade winds regime. The flight pattern consisted of (i) repetitive low level (30 m) "L-shaped" tracks along the radar and optical paths with the two legs intersecting at the R/P FLIP about 8.5 km off the coast, (ii) profiles through the marine inversion to the trade-wind inversion and (iii) stacks above FLIP and at about 75 km upwind from the FLIP. Results showing the variability of the momentum, sensible heat and latent heat fluxes as well as that of meteorological variables are presented. The aircraft eddy correlation fluxes are compared to bulk fluxes obtained from the TOGA COARE bulk algorithm. The aircraft results are also compared to those obtained by the FLIP. Flux divergence was determined from the several stack runs. Data from the aircraft soundings were used to determine the vertical structure of the MABL.