隐身技术是指减缩和控制作战平台及武器系统可被敌方用来探测、跟踪、识别和攻击的各类信号特征，使武器系统难以被发现、跟踪、识别和攻击的一门综合性高技术。隐身武器装备是现代和未来信息化战争的重要特征，进入二十一世纪以来，随着隐身技术的成熟与发展，应用该技术的作战平台已经发展到了军用无人飞机等新式军用飞行器。根据重点预研究课题的需求，为研制满足未来战略、战术侦察需求的高高空长航时无人侦察平台，本文从飞机的RCS散射水平与飞机生存力相互关系研究角度入手，以工程研制为目标，完成了高隐身指标体系论证和总体方案设计，并进行了概念方案阶段验证。通过创造性地提出工程化的飞机隐身设计流程，综合运用低RCS外形、隐身材料等技术，设计出满足高高空长航时无人机任务需求和威胁环境要求的雷达隐身总体设计方案。通过对无人机未来使用环境的分析，确定了保证其具有较高生存力的雷达隐身指标。针对该隐身指标，运用RCS数值计算与仿真优化、缩比模型RCS测试等手段，验证了多种隐身方案的可行性，摸清了不同隐身措施对整机RCS减缩效果的优劣，并从理论上分析了各种现象产生的原因。其中，对于无人机前向最主要散射源进气道的RCS减缩，设计了吸波导流环、吸波格栅等具有较高技术含量的隐身方案；为抑制机翼前缘的散射峰值而设计的玻璃钢透波前缘结合尖劈结构的方案在国内是首次使用。最终整机的测试结果表明，优选的隐身方案可以满足无人机雷达隐身指标要求，有利地保障了该型无人机的顺利研制。
Stealth technology is a synthetic high technology, with reducing and controlling a variety of signals for the combat platform and weapon system, which can be detected, tracked, identified and attacked by the enemy. Stealth weapon system plays an important role in the current and future information wars. From entering 21st century, with the maturity and development of the stealth technology, the new military vehicle (such as military unmanned vehicle), which is included in the combat platform, has already used the stealthy technology.According to HALE subject, for developing high-altitude long endurance unmanned reconnaissance platform which meets the future strategic and tactical reconnaissance requirements, the study in the paper is based on the relationship between the aircraft RCS and the aircraft survivability and is designed to be used in the engineering development phase, accomplishing high stealthy merit system demonstration, initial conceptual design, and conceptual design phase demonstration. By the stealth aircraft design flow, utilizing the low-observable shape and application of RAM(Radar Absorb Material), a practical scheme of stealth HALE(High Altitude& Long Endurance) UA(Unmanned Aircraft) is laid out that adapts it to the battlefield environment. The RCS level of UA that has enough survivability to achieve its goals is confirmed by the analysis of the battlefield environment. For getting the RCS level, a design of UA stealth project was performed by means of numerical simulation and subscale model RCS test. Different RCS reduction measures are validated and compared with each other. The principles of the RCS reduction induced by the measures are shown. For the most important scatter source, the advanced radar absorber devices are used in the inlet. For reducing the scatter peak of the wing edge, glass fibre reinforced plastic edge is used. At last, the test result confirmed that the UA achieved its RCS level in all azimuth what ensured the development of UA.
