Putting the Pieces Together
A Patriot battery has three basic pieces, all portable: launch platforms containing Patriot interceptor missiles, a radar station that scans the skies, and a manned control station. But its information systems are immensely complex. As its radar tracks objects in the air, the system’s computers calculate the objects’ altitudes, speeds, and trajectories to identify planes as friendly or hostile, and even to discriminate among various types of missiles and identify where they will land.
At the control station, the computers’ conclusions are displayed as a variety of icons on a screen. The system also exchanges coded signals with friendly planes that effectively demand, “Identify: friend or foe” (these are known as IFF codes). Each interceptor carries its own radar and guidance system; as it rockets skyward at supersonic speed, it tracks its target and adjusts its course as necessary.
So what went wrong in 2003? In the most recent official postmortem, in January, the Defense Science Board–an investigative task force appointed by the U.S. Department of Defense–gave some summary answers. While concluding that the Patriot was a “substantial success” because it had shot down eight Iraqi missiles and possibly a ninth, it also offered three criticisms. First, it suggested that the Patriot system was overdeployed, which was the logical result of flawed intelligence about the strength of Hussein’s military. U.S. forces deployed 40 Patriot batteries, and coalition nations contributed another 22 batteries. This problem was magnified by another: the 40 U.S. batteries were set to function with a high degree of automation, paving the way for identification errors to produce fatal results. “The operating protocol was largely automatic, and the operators were trained to trust the system’s software…a design that would be needed for heavy missile attacks,” the task force wrote.
The second problem, said the board, was a communications failure. For one thing, the IFF system “performed very poorly.” But more significantly, the Patriot batteries had little or no contact with other military systems, such as the radar planes known as AWACS, which were tracking friendly planes and, in theory, could have told the Patriot batteries to hold their fire. “We tend to assume that data are routinely communicated from one system to the other,” the task force wrote. “The Task Force believes that we are a long way from that vision….[A] Patriot battery on the battlefield can be very much alone.”
But the Patriot itself was also fraught with problems, the board concluded. “The third shortfall was the Patriot system operating philosophy, protocols, displays, and software….The solution here will be more operator involvement and control in the functioning of a Patriot battery, which will necessitate changes in software, displays, and training.” But what does this mean, exactly?
“The unclassified stuff is pretty vague,” says John Pike, director of Globalsecurity.org, a Washington think tank. Raytheon and members of the Defense Science Board declined interviews for this story; the army and U.S. Central Command (the joint body that had overall command during the war) did not comment beyond their official reports. In a statement, the army said it was already repairing problems with the Patriot. “These corrective actions include combinations of hardware modifications, software changes, and updates to tactics, techniques, and procedures,” it says.
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