In October of 2015, a tether balloon (or aerostat) that was part of the US Army’s Joint Land Attack Cruise Missile Defense Elevated Netted Sensor (JLENS) system broke free from its moorings at the Aberdeen Proving Ground in Maryland. The 243-foot-long helium balloon led the military on a merry chase, taking out power lines with its mooring cable, before settling to the ground several hours later.
A JLENS balloon like the one that got loose over Maryland.
The JLENS balloon’s runaway escape was an embarrassment for a program that’s been labelled a “zombie,” “costly, ineffectual, and seemingly impossible to kill,” but it was hardly the first time a military aerostat has gotten loose to wreak havoc. In 1981 the first military aerostat to enter service since the end of the Second World War, a blimp with the project codename SEEK SKYHOOK and the unofficial nickname “Fat Albert,” got free of its tether on Cudjoe Key in Florida and almost lifted a fishing boat that tried to corral it free of the water before being shot down by two Air Force jets.
The SEEK SKYHOOK aerostat, which entered service in 1974, inaugurated a second era of tethered military balloons that’s already about as long as the technology’s first era – which lasted from the Japanese use of an observation balloon over Port Arthur in 1904 until the decommissioning of the barrage balloons operated during the Second World War.
SEEK SKYHOOK was an air search radar (an AN/DPS-5, to be precise) deployed to the Florida Keys to offer better warning of aircraft approaching from Cuba. Most subsequent aerostats were also intended for air defense. That included the Low Altitude Surveillance System (LASS) purchased by Kuwait in the late 1980s to add to their air defense system. The LASS, one of which was also purchased by Saudi Arabia, combined a 71-meter-long balloon built by TCOM, L.P. with a Westinghouse AN/TPS-63 radar like that used for short-range warning by the US Marine Corps. Though the LASS was intended to spot low-flying aircraft its position at 10,000 feet meant it had some capacity to watch ships or ground vehicles too.
That additional capacity meant it played an important part in the early hours of the Iraqi invasion of Kuwait in 1990. The LASS system was still in the testing phase, being operated by a mixed team of contractor personnel and Kuwaiti air force officers. Early on the morning of August 2, the operators watched “a big burst of light – a solid line of target returns” crossing the border. Clifford Gobbitt, a TCOM systems engineer on duty, recalled that “there was so much metal, it was saturating the display.” A few hours later the TCOM staff turned the balloon and its radar over to the Kuwaiti Air Force and began the process of extracting themselves from what was about to become a war zone. A few months later, TCOM’s vice president of marketing told Aviation Week and Space Technology that “the TCOM aerostat system got the first detection of the invasion, and that warning allowed the Emir and his family to escape.” The balloon was destroyed within the next few days, but the Kuwaitis must have been satisfied with the results. Once the war was over they put in an order for an upgrade system of the same type.
The Kuwaiti experience on the eve of the Gulf War was a preview of sorts for what would be expected from one of the stand-out successes of the war, the Joint Surveillance Target Attack Radar System (JSTARS). Like the Kuwaiti LASS, JSTARS used an aerial radar to track the movement of enemy ground forces. Unlike the LASS, JSTARS was built for that task and that task only. Only two experimental aircraft were ready when the war began, and interpreting their information was apparently not much easier than reading the radar returns the TCOM technicians had seen. Colonel Martin Kleiner, the Army’s project manager, recalled that “the aircraft was airborne, it was down-linking radar and the ground stations were receiving it. Quite frankly, we had no idea what we were looking at. Our application of the system was pretty much being developed on the fly.” Still, they proved themselves indispensable in several battles. After the war, Air Force Chief of Staff General Merrill McPeak said “We will not ever again want to fight without a JSTARS kind of system.”
August 2nd was also the swan song of balloon-borne ground surveillance radar. Though JSTARS and similar programs spawned a series of aircraft-mounted radar systems, the surveillance aerostats used by the US government in places like Afghanistan, Iraq, and the US border with Mexico tend to be designed for low-intensity conflicts and equipped with video cameras rather than radar.