text: AVIRIS has been flown on four aircraft platforms:  the NASA ER-2 jet, Twin Otter Internationals turboprop, Scaled Composites Proteus, and NASAs WB-57. The ER-2 flies at approximately 20 km above sea level, at about 730 km/h. The Twin Otter aircraft flies at 4 km above ground level at 130 km/h. AVIRIS has flown North America, Europe, portions of South America, and Argentina.