After over half a century of effort, blimps (helium filled lighter-than-air aircraft) have returned to favor on the battlefield. The last time blimps were widely used was World War II, when hundreds roamed coastal waters looking for enemy warships (mainly German submarines), and thousands of tethered ones served to prevent low altitude bombing attacks. The U.S. continued to use blimps for maritime patrol until the early 1960s, and advocates have been trying to get blimps back into action ever since. Now, combat commanders can't get enough blimps in Afghanistan. But the new blimps are stationary.
The U.S. already has dozens of aerostats (tethered blimps) in Afghanistan. These have proved to be a powerful intelligence and security tool against the elusive Taliban. In the last few years, the U.S. Army has combined communications and electronic eavesdropping gear and software, with day/night camera towers, and aerostats, to produce systems that use software to constantly scrutinize the digital video for anything suspicious. Human operators are always on duty to scrutinize anything suspicious, and sound the alarm if hostile activity is spotted. This combination of high-resolution vidcams, aerostats and image analysis software has created a powerful battlefield intelligence tool.
While tower mounted vidcams are more common, systems like RAID (Rapid Aerostat Initial Deployment), which uses a blimp floating at about 320 meters (a thousand feet) up, tethered by a cable that provides power and communications to the day and night cameras up there, have proved more useful. That's because at 320 meters, a radar on the aerostat can detect vehicles out to 200 kilometers, and vidcams can see over many of the nearby hills found in Afghanistan (and not so much in Iraq.) It's like having a 24/7 UAV, equipped with radar and vidcams. The aerostats have been particularly useful at watching over the new highways built in Afghanistan. In the south, these new roads go for long distances on fairly flat ground. That's one reason why the army wants to more than double its force of 30 aerostats in Afghanistan.
There are some problems with aerostats. One is ground fire from rifles and machine-guns. Afghans, in particular, like using the RAID blimps as targets. Rifle fire won't destroy the blimps, but does cause them to be brought down more frequently for repairs. Normally, the blimps can stay up for 30 days at a time, but the bullet hole repairs have some of them coming down every few days.
In Iraq it was soon found that tower mounted cameras were just as good as the aerostats, in most situations, and much cheaper. Thus in Iraq there were more than twenty times as many tower systems as aerostat-based ones. Tower mounted systems are still used widely in Afghanistan, but only for keeping an eye on the area around bases. Nearby hills are more common in Afghanistan, and these block the view of tower mounted vidcams.
Thus while aerostat systems cost up to $10 million each, the army still buys things like the Eagle Eye mobile surveillance tower system for about $600,000 each. This is a security system of day/night cameras, laser range finder and designator, all mounted on a truck mounted tower.
Since 2003, the original static towers have gotten more mobile, and grown taller. The tallest Eagle Eye tower is 34.5 meters (107 feet) tall, allowing the cameras to spot vehicles up to 25 kilometers away. Great for keeping an eye on thinly populated areas in a desert, which western Iraq and many parts of Afghanistan, have plenty of. The earlier ten meter (30 foot) tower can see out to eleven kilometers, the 20 meter (60 foot) tower out to 16 kilometers and 27 meter (84 foot) tower out to 20 kilometers. The ten meter tower was adequate for most situations, which usually involved guarding a base, but the taller tower also serves as a communications relay for widely dispersed troops. The towers can be easily taken apart or erected by troops. When temporary bases are set up, an Eagle Eye tower provides the equivalent of a permanent UAV presence, which, just by being there, tends to discourage attacks, or any misbehavior in the vicinity of the base.
The tower and aerostat vidcams are more than just surveillance systems. Operators have radio links to nearby bases, and the towers and aerostats in those bases. Thus bases can call on each other for help in chasing down any hostiles spotted, as well as using video or electronic information each tower might pick up on the bad guys. This kind of surveillance makes it more difficult for the enemy to sneak around bases, either to collect information, plant a roadside bomb, or set up an ambush. The software used in these surveillance systems contains many intelligence tools, and links to databases. Thus operators can reveal seemingly innocent behavior as part of something more sinister, and preventable.
The army has cobbled together an intelligence system that increasingly "fuses" data from UAVs, as well as tower and aerostat vidcams (and other sensors) to give 24/7 coverage of large areas. Since the cameras have night vision, or even thermal imaging (heat detecting) capabilities, and often radar, it's very difficult for anyone to come near, and not be spotted and scrutinized. On the down side, ground and air forces have to be available 24/7 to take advantage of any new sightings of enemy forces. All this new information has made American troops 24/7 warriors.