安全与隐私buzzfeed.com
展示 FBI 飞机空中监视地点的地图
Maps Showing Where FBI Planes Are Watching from Above
2016 — 2017，它一次次回到首页
黑点是上首页（≥ 50 分）的那次投稿，空心点是没冲上去的投稿，点越大分数越高。
导读
这篇 BuzzFeed 报道用公开航班追踪数据制成地图，标出 FBI 飞机在美国城市上空盘旋、网格飞行的轨迹，并讨论这些空中监控飞行可能用于什么。它把原本不透明的执法空中监视变成读者可以查看和自行追踪的图景。
为什么经久不衰：它用公开数据揭开了空中监控的一角，让普通人能自己查看和验证，因此多年后仍值得读。
HN 评论精选
教读者用公开 ADS-B 网站实时查看疑似执法/侦察飞机的飞行轨迹，并给出当天实例。
想自己看实时数据的人可以去 adsbexchange.com，点 Global Radar View，再点 Menu、Options、Filters，启用 Interesting 过滤器。今天是周日，活动不多，但目前有一架 FBI 的 Cessna 在华盛顿特区以西盘旋；还有一架飞机在洛杉矶以东做网格飞行，注册在弗吉尼亚的 Dynamic Aviation Group 名下，这家公司提供空中情报、监视和侦察（ISR）等服务。
brbsix查看英文原文
For anyone who wants to see the live data for themselves, go to http://www.adsbexchange.com/, click 'Global Radar View'. Then click 'Menu', 'Options', 'Filters', then enable the 'Interesting' filter. It's a Sunday, so there's not too much activity. However there's currently an FBI Cessna circling west of Washington D.C. [0] There's also a plane gridding east of LA. [1] It's registered to Dynamic Aviation Group out of Virginia, a company that provides aerial intelligence, surveillance, and reconnaissance (ISR), among other things. [2] [0]: http://i.imgur.com/8c0RQ9H.png [1]: http://i.imgur.com/Yki2UTs.png [2]: http://www.dynamicaviation.com/flight-solutions-and-services/intelligence-surveillance-and-reconnaissance/
把文章放进“持续广域空中监视”的技术与伦理背景中。
这让我想起 Radiolab 的一期节目：2004 年伊拉克路边炸弹伤亡上升时，Ross McNutt 团队用一架小飞机和 44 兆像素相机全天候俯瞰整座城市；炸弹爆炸后可放大该地点并回放时间，看到是谁放置的。战后他把这项持续监视技术带回美国，从墨西哥华雷斯到俄亥俄代顿，节目最后问：知道能做之后，我们是否应该做。
drhodes查看英文原文
reminds me of a radiolab episode: http://www.radiolab.org/story/eye-sky/ here's the summary, > In 2004, when casualties in Iraq were rising due to roadside bombs, Ross McNutt and his team came up with an idea. With a small plane and a 44 mega-pixel camera, they figured out how to watch an entire city all at once, all day long. Whenever a bomb detonated, they could zoom onto that spot and then, because this eye in the sky had been there all along, they could scroll back in time and see - literally see - who planted it. After the war, Ross McNutt retired from the airforce, and brought this technology back home with him. Manoush Zomorodi and Alex Goldmark from the podcast “Note to Self” give us the low-down on Ross’s unique brand of persistent surveillance, from Juarez, Mexico to Dayton, Ohio. Then, once we realize what we can do, we wonder whether we should.
推测这些飞行是在采集高清影像/3D 模型，并可能用红外寻找室内活动。
根据文中信息我猜测：飞机通常只在工作日出现，说明任务一般不急；机上有高质量相机；航迹显示它们反复绕同一地点，但似乎不会连续数小时。苹果做地图时也曾低空飞行拍摄城市多角度高清照片，再处理成 3D 模型；卫星太贵、受云层和角度限制，画质也不如飞机。所以我猜他们在做类似的事：拍摄感兴趣地点的高清图像并建立 3D 模型备用。另外从 FLIR 相机看，也可能在找室内种毒品或人员聚集。
danielrhodes查看英文原文
Here's my guess based on the following info: - The article points out that the planes are typically only seen M-F, which suggests that what they are doing is usually not time-sensitive. - They mention the planes have a very high quality camera on board. - From the flight patterns, you can see they repeatedly circle the same location, but not apparently for hours and hours at time. When Apple first released their Maps product, it was revealed that they also flew planes at low altitude to capture super high quality pictures of cities at different angles. They would then process the data later and create 3D models. [1] Satellites are too expensive to use for this sort of thing, are affected by cloud cover and non-optimal angles, and won't be higher quality than what you can capture from a plane. So my guess is they are doing exactly what Apple was doing: capturing high quality images of various points of interest and then creating 3D models in case they need to use them later. Another thing they are probably looking for (from the mention of the FLIR camera) is people growing drugs in their basement or perhaps where people congregate in a building. They probably find this useful for among other things, having very up to date photography of a particular area, and also in case they need it for some operation like a raid. [1] http://www.applegazette.com/apple-inc/how-apple-creates-3d-flyover-maps/
用前警用飞机的改装记录说明执法空中监视确实会做降噪隐蔽处理。
我有一架 Cessna 182，最初属于华盛顿州警察。他们拥有时加装了汽车式消音器（飞机通常没有消音器）用于隐蔽监视，卖给我前全拆了。Form 337 历史记录里有相当完整的描述，见第 27 和 55 页。
repiret查看英文原文
I own a Cessna 182 that was originally owned by the Washington State Police. While they owned it they added an automotive-style muffler (planes don't normally have mufflers) to use it for stealth surveillance. They tore that all out before they sold the plane. There's a pretty complete description of what they did in the Form 337 history: http://mike.laiosa.org/N6594E/Airworthiness.pdf - see in particular pages 27 and 55.
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