美国的七件“国防神器”

布利泽轨道炮

    通用原子公司（General Atomics）最出名的产品当属它的“猎食者”和“收割者”无人机，不过它的一项海军武器也同样充满未来主义色彩，这就是它的布利泽轨道炮项目。

    轨道炮是电磁炮的一种，它通过小心地引导电流通过两段平行导轨所产生的磁场对弹丸进行加速，它的弹丸可以是任何东西，可以是一架飞机也可以是一枚炮弹，美国海军研究室已经对轨道炮研究了很长时间，希望未来能够用它来代替传统舰炮，因为轨道炮的弹道更平稳、射程更远，而且杀伤力更强。在美国海军的测试中，轨道炮的弹药速度已经超过了每秒钟1.5英里，与轨道炮未来的最终潜力相比，这还仅仅是一个开始。

    不过轨道炮现在还没有完全做好服役的准备，一方面是由于它电力消耗巨大，一方也是由于轨道炮技术尚不完全成熟。通用原子公司此次带了一件轨道炮的原型模型来参加展会，只是为了展示这项技术的研究程度和武器设计。不过通用原子公司并不是唯一一家花大力气研发轨道炮技术的公司。BAE系统公司也为美国海军研发了轨道炮原型产品，而且波音公司的鬼怪工程部（Phantom Works）也启动了用于轨道炮的精确打击弹药的研发。

Blitzer Rail Gun

    General Atomics is best known for its Predator and Reaper drones, but where Naval warfare technology is concerned it has something equally futuristic in the works: its Blitzer Railgun program.

    Railguns are electromagnetic projectile launchers that accelerate their payloads -- which could be anything from an aircraft to an artillery round -- by carefully manipulating an electromagnetic current running the length of two parallel rails. The Office of Naval Research has long researched railguns as potential future replacements for its naval surface guns, as they launch projectiles on flatter trajectories to much greater distances with far more devastating force. In U.S. Navy tests, railguns have launched projectiles at speeds in excess of 1.5 miles per second, and that's really just the beginning of what railguns could eventually do.

    While railguns aren't quite ready for service -- aside from being too energy intensive, the technology isn't completely reliable just yet -- General Atomics brought a prototype to Sea-Air-Space simply to show off how far they've come with both launcher and projectile design. But General Atomics isn't the only defense company heavily into the railgun race. BAE Systems has also developed railgun prototypes for the Navy, and Boeing's Phantom Works has developed precision sabot projectiles for railguns to launch.