Effects of Wing Sweep on Stability of a 5th-Generation Fighter Configuration

摘要

The Fifth Generation Target Study (5GTS) was a conceptual design task for a large target drone aircraft capable of representing key 5th generation fighter signature and performance attributes. The target drone's intended uses are to test air-to-air and surface-to-air missiles, and to ensure that modern tracking systems are capable of identifying and targeting 5th generation fighters. Five candidate 5GTS configurations, each with a different wing leading-edge sweep angle, were tested in the United States Air Force Academy (USAFA) subsonic wind tunnel. Three of these were tested with both four-post and butterfly tails. This testing revealed generally poor lateral-directional stability for configurations with 4-post tails and wings with sweep angles less than 42 degrees. On these configurations, butterfly tails gave superior lateral-directional stability but suffered from pitch-up. Delta-wing configurations exhibited the most linear stability characteristics. Models were also tested with and without sharp-edged inlet/strake structures attached to the fuselage ahead of the wings. The presence or absence of these inlet/strakes had a relatively minor effect on stability characteristics.