July 6, 2011: The U.S. Army has successfully tested its new Starlite radar in one of its aerostats (stationary recon blimps). The AN/ZPY-1 Starlite lightweight radar weighs 29.5 kg (65 pounds), occupies 34 cc (1.2 cubic feet), uses 750 watts of power and costs about $2.3 million each. Starlite can deliver photo quality black and white images of what is down there, in any weather. The army has developed software that enables the Starlite images to be transmitted to existing army video terminals, and automatically appear on electronic versions of standard army maps. Starlite is used in combination with vidcams and heat sensors (infrared or thermal). The Starlite software enables the operator to quickly, or automatically, point a video camera at anything the Starlite can see. The army has 33 Starlites in service or on order.

The Starlite was originally designed for use in the army's new 1.5 ton MQ-1C Sky Warrior UAV. While UAVs get more publicity, the army has found that "stationary UAVs" (helium filled aerostats or tall towers) not only do the job, but do it a lot cheaper (under $1,000 an hour, mostly for maintenance, repairs and personnel to monitor the sensors) and stay airborne nearly all the time. Compare this to Sky Warrior or Predator, which costs $6,000 an hour to fly, and Global Hawk, which 4-5 times more. Global Hawk is so expensive partly because of the high end sensors used. Not everyone needs the high flying Global Hawk, or even a Sky Warrior. They just need a way to keep an eye on a large area (like a chunk of the Syrian, Iranian or Pakistani border, or the area surrounding a base) 24/7. The PTDS (Persistent Threat Detection Systems) that are mounted in the aerostats or towers are a much cheaper alternative to mobile UAVs. Starlite is now another component of the PTDS.

All this is a recent development. It was only seven years ago that the U.S. Army sent 22 blimps (aerostats, actually) to Iraq and Afghanistan. The most common model of aerostats float at about 330 meters (a thousand feet) up, tethered by a cable that provides power and communications to the day and night cameras, or Starlite radar, up there. The big problem was ground fire from rifles and machine-guns. Hostile gunmen liked using the aerostats as targets. Rifle fire would not destroy the aerostats, but did cause them to be brought down more frequently for repairs. Normally, the aerostats can stay up for 30 days at a time, but the bullet hole repairs have some of them coming down every few days. The PTDS surveillance systems mounted on tall steel towers also suffer gunfire damage, but rarely any that disables the equipment.

The first army aerostats went to Iraq to help defend offshore oil facilities from attack by terrorist speedboats. Those early systems used a 75 meter (233 foot) long, helium filled, unmanned aerostat equipped with radar and other sensors. These aerostats were about 2.5 times the size of the more familiar advertising blimp. Aerostats are blimp like vehicles designed to always turn into the wind and stay in the same place. These larger aerostats were originally designed to detect cruise missiles, and were soon replaced by smaller and cheaper aerostat systems currently in use.