The fiber performance and potential as a reinforcement for fiber composites of a special PAN-based graphite fiber were evaluated by testing the fiber's tensile properties in an epoxy matrix. Representative strand samples were taken from 30 spools (∼4 kg) of single-end, 1500-filament fiber to make over 5000 fiber-epoxy strand specimens using the filament-winding process. Characteristics studied were fiber uniformity, strength and modulus distributions at room and liquid nitrogen temperatures, stress-strain behavior, the effect of strain rate on fiber strength, and acoustic emission during tensile loading to failure. The fiber was found to have a 3570-MPa (517 ksi) failure stress, a 1.7 percent failure strain, a 206-GPa (30 × 106 psi) modulus, and a density of 1.77 Mg/m3 at 23 °C (73 °F). Liquid nitrogen temperature and various strain rates had no significant effect on fiber tensile properties.