曝光台 注意防骗
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RQ-2/Pioneer
RQ-2A. The reliability analysis for early-model Pioneers is based on statistical data gathered between September 1990 and April 1991 from three Marine, two Navy, and one Army Pioneer unit (total of six systems) while deployed in the Persian Gulf theater in support of Operations Desert Shield and Desert Storm. Although known as the Option II+ version of Pioneer at that time, this model was subsequently designated as the RQ-2A. At the time of this data, it had been in service with the Navy for four years, the Marines for three, and the Army for one. By this time, it had already incorporated a number of reliability improvements to its original, imported version.
With respect to its Operational Requirements Document, the early model Pioneer achieved less than desired reliability metrics. This could be due to one of several factors. First, the Pioneer was purchased from Israel as a non-developmental system in an accelerated procurement. Once in operation, Navy and Marine users quickly identified several deficiencies that contributed to unreliability. General Charles C. Krulak, then Commandant of the U.S. Marine Corps noted “the Pioneer does not have an automatic take-off, landing, or mission execution capability and that has led to a high accident rate.” Shipboard electromagnetic interference caused several crashes, and the engines were thought to be too small and easily overstressed. In addition to the need for a more reliable engine, the Marine Corps users also felt that the system needed a smaller logistical footprint and a longer endurance.
RQ2-B. The currently fielded version of Pioneer, the RQ-2B, is essentially a digital version of its analog predecessor, with the major distinction being the replacement of the analog air data system with the digital Modular Integrated Avionics Group (MIAG). RQ-2Bs are modifications of the existing RQ-2A airframes, rather than new production. All twenty-five operational (out of 49 existing) RQ-2As have been converted to RQ-2Bs.
The reliability analysis for later model Pioneers is based primarily on the Marine Pioneer squadrons’ (VMU-1 and VMU-2) operations in the late 1990’s. The reliability data for the RQ-2B is derived from two sources: maintenance aborts and in-flight aborts. Each offers a somewhat different perspective on the reliability of the overall aircraft. In a distribution closely resembling that of the Predator RQ-1A data, the majority of the failures (66 percent) are attributable to the combination of malfunctions in flight control, power, and propulsion. The breakout in the flight critical systems is roughly 25 percent flight control failures and 75 percent power and propulsion failures. (Recall the corresponding RQ-2A data showed failures due to power and propulsion and flight control equally divided.) This suggests an improvement in the flight control system of the Pioneer over time, or perhaps a shift in emphasis from power and propulsion concerns. The latter is unlikely, however, given that the planned (1997) conversion from the Sachs to the more reliable Quattra engine was never accomplished.
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无人机系统路线图 Unmanned Aircraft Systems Roadmap(184)
