The Shadow 600, a larger version of the 200, is still being tested. The 600 weighs 585 pounds and carries 85 pounds of surveillance and communications equipment. The 600 can stay in the air for up to 14 hours with the same speed as the 200. It's range (220 kilometers) is limited by the range of its communications. The 600 can fly higher, to 17,000 feet, which helps it avoid ground fire if that is a problem. With it's larger payload, the 600 can carry more powerful cameras, or an SAR radar (which generates murky, but recognizable images of anything down there, in any weather.) The 600 is also designed to use a laser designator and work with missile firing helicopter gunships.
The Shadow series of UAVs are largely the result of camera and communications equipment getting smaller, more reliable and cheaper. The Shadow 200 is also small (13 foot wingspan) and quiet. It can be seen, and shot at, in day time, but at night is hard to spot. Since the U.S. Army prefers to fight at night, the shadow is the ideal reconnaissance tool.
Each Shadow 200 platoon has three aircraft and half a dozen vehicles. Each unit costs $11 million, with each aircraft costing $1.5 million. Most of the cost is for the electronics. The big question mark with the Shadow UAVs is attrition. The Shadow aircraft, while smaller than the Predators, will be flying lower, at 10,000 feet and lower. This makes it a target for Stinger class portable missiles. While the 52 horsepower Shadow engine doesn't give off much heat, it may be enough for the more modern missiles. But the biggest enemy of the Shadow will be wind. Gusts that would not be felt in an F-16, and would jerk a Predator about, could bring a Shadow down. Loss of control is a worse problem with UAVs, because the pilot can't "feel" what's going on and has to work just with instruments. The lighter the UAV, the worse the problem. Iraq is a windy place.
While the Predator (UAV) unmanned recon aircraft has been getting a lot of attention because of it's success in Afghanistan and elsewhere, it's not the only UAV that will see use in, say, an invasion of Iraq. The U.S. Army has developed it's own, smaller, UAV that will scout for brigade and division commanders. This is the RQ-7 Shadow 200 UAV (and a larger version, the Shadow 600.) While the Predator weighs a ton, the Shadow 200 320 pounds and carries 50 pounds of surveillance and communications equipment. The 600 can stay in the air for up to six hours and move along at up to 200 kilometers an hour. Cruise speed is 155 kilometers an hour, and when just flying around a area it's keeping an eye on, speed is usually 120 kilometers an hour. It's range (77-125 kilometers) is limited by the range of its communications. Normally, the 200 flies at 10,000 feet, but can go up to 14,000. The biggest problem with the 200 is its light weight. If the weather is bad, the aircraft gets bounced around and this causes control problems. The 200 lands and takes off like a normal aircraft (needing about a hundred meters of flat ground), although there is a catapult available for takeoffs and the aircraft can be brought down via a built in parachute as well. Sensors include day/night video cameras that transmit still pictures or low resolution video (max transmission speed of data is only 19k baud, since most web users have a 56k baud modem, you can see how limited this is.) Since the 200 carries a GPS, the location of anything it spots can be accurately plotted for attacks by artillery, helicopters or warplanes. The camera onboard can identify vehicles 3.5 kilometers away, day or night. The Shadow 200 has been in development since the late 1990s and just completed realistic, and successful, field tests with an army combat brigade. A navy version, for use from ships, is called the Shadow 400.