An Air Force official revealed on December 4th that the service is "developing a stealthy unmanned aircraft system (UAS) to provide reconnaissance and surveillance support to forward deployed combat forces." The UAV had been discussed on the Ares technology blog, as well as elsewhere online, but the USAF statement to Aviation Week was the first to detail the aircraft.
The RQ-170 is flown by the 30th Reconnaissance Squadron at Tonopah Test Range, Nevada, home of the F-117 stealth fighter when the program's existence was secret — and falls under Air Combat Command's 432d Wing at Creech Air Force Base, Nevada. At Kandahar, the Sentinel was seen operating out of General Atomics Aeronautical Systems' hangar. The RQ-170 designation is similar to that of the F-117 — a correct prefix, but out of sequence to avoid obvious guesses of a program's existence. Technically, the RQ designation denotes an unarmed aircraft rather than the MQ prefix applied to the armed Predator and Reaper UAVs. The USAF phrase, "Support to forward deployed combat forces," when combined with observed details, suggest a moderate degree of stealth (including a blunt leading edge, simple nozzle and overwing sensor pods) and that the Sentinel is a tactical, operations-oriented platform and not a strategic intelligence-gathering design.
Many questions remain about the aircraft's use. If it is a high-altitude aircraft it is painted an unusual color — medium grey overall, like Predator or Reaper, rather then the dark gray or overall black that provides the best concealment at very high altitudes. The wingspan appears to be about 65-ft., about the same as an MQ-9 Reaper.— all taken from the left side — the impression is of a deep, fat centerbody blended into the outer wings. With its low-observable design, the aircraft might be useful for flying the borders of Iran and peering into China, India and Pakistan for useful data about missile tests, telemetry as well as gathering signals and multi-spectral intelligence. (Source: Aviation Week)