Export restricted (ITAR), sale only to US Citizens and Organizations. Desirable Apollo-era Angle of Attack Sensor System, commonly called the Q-Ball, measuring approximately 18.5" tall and 13.25" in diameter across the base, with a Nortronics/Northrop plaque on the base: "F16 Q Ball, Part No. 22620000-1, Serial No. 11, Contract No. NAS8-2583." In very good to fine condition, with wear to the exterior and the identification plate re-glued to the base.
Although the mature version of the Apollo Q-Ball that flew on the manned flights was of a different design under a different contract, this piece represents developmental work toward that end. According to NASA Technical Memorandum TM X-53462: "A complete Q-ball package known as the F-16 was flown on Saturn SA-4 through SA-7 vehicles. This is a normal Q-ball which has a 2-inch nose radius." These were uncrewed test flights of the Saturn I launch vehicle; the Q-ball which would become part of the Saturn V Emergency Detection System (EDS) had a 4-inch nose diameter and eight ports on the nose, compared to the six ports on the F16 model. The Q-ball package measured pressure change differentials between the ports, which were used to compute aerodynamic incidence angle and dynamic pressure data. This data helped to determine whether or not the rocket was flying on course, and allowed the flight computer to make minor corrections to the trajectory.
