The TCSP ER-2 Navigation Data contains information recorded by the on-board navigation and data collection systems of the NASA ER-2 high-altitude research aircraft. In addition to typical navigation data (e.g., date, time, latitude/longitude, and altitude) it contains outside meteorological parameters such as wind speed, wind direction, and temperature. These data were collected during the Tropical Cloud Systems and Processes (TCSP) field campaign in July 2005, with flights based out of Juan Santamaria Airport in San Jose, Costa Rica. The main goal of the campaign was to gain further insight into the structure and lifecycle of tropical weather systems. These navigation dataset files are available from July 2 through July 27, 2005 in ASCII and PDF formats.