The Performance of the Patriot Missile in the Gulf War
Lessons learned then are applicable today
I am trying something different with this post. Because of the heightened interest in the Patriot missiles deployed to Ukraine, I am publishing today an excerpt from the 1992 staff report to the Government Operations Subcommittee on Legislation and National Security on our 10-month investigation into the performance of the Patriot missile in the Gulf War. I was then deputy director of the subcommittee and lead a bipartisan investigative team of staff and experts from the General Accounting Office, Congressional Research Office and Office of Technology Assessment. We concluded that the best evidence indicated that the Patriot hit between zero and four of the 44 Scuds it engaged.
The Patriot is much improved and should be able to hit some of the ground- and air-launched ballistic missiles Russia is using to attack Ukrainian cities. But these are difficult targets, traveling many times the speed of sound. The methodology we used and the questions we asked may be useful for all examining the the performance of this system today.
By itself, the investigation is a fascinating look at perception and reality. I believe it remains the only independent investigation into the performance of a missile defense system in combat, and one of the few into any major weapon’s combat performance.
This examinations will not be for everyone. But it is easy to delete from your inbox.
For additional background, please see my article from last week.
Patriot Perceptions
During the Persian Gulf War, Americans were flooded with dramatic video footage that they were told showed Patriot missiles destroying Scuds. This was reinforced by official Army, Raytheon and Administration statements that the Patriots had destroyed almost every incoming Scud.
What wasn't made clear at the time was that the explosions in the sky were not caused by Patriots directly hitting the incoming Scuds, but, rather, by proximity fuzes as the Patriot neared a Scud or a Scud fragment, or by the missile automatically self-destructing after missing a Scud, or by Patriots flying after false targets.
Original Views of Performance in the Gulf
During and after the Gulf War, the Patriot missile system was universally praised for what was perceived to be its almost perfect record in destroying Iraqi Scud warheads. Assessments of the Patriot's performance in the war were prepared by the Patriot Program Office and briefed to high-ranking Administration officials and Members of Congress who accepted these claims. Members were told that Patriots had intercepted 89% of the Iraqi Scuds launched against Saudi Arabia and 44% of the Scud warheads directed against Israel.
Independent experts slowly began to questions these claims, however, based on Israeli evaluations and their own examination of the video tape record of the engagements. In December 1991, the Subcommittee on Legislation and National Security investigators began their review by contacting officials from the U.S. Army and the prime contractor for the missile system, the Raytheon Company.
Initially, officials from the Army and Raytheon told Subcommittee investigators that they were confident that the Patriot had achieved a high rate of success and they did not see any reason for the Subcommittee to investigate. They believed the questions about the system's performance stemmed from Israeli officials interested in promoting the Israeli effort at tactical ballistic missile defense -- the Arrow -- and from one or two critics.
On January 24, 1992, four Army officers gave Subcommittee investigators what they described as the standard briefing on Patriot performance in the war. This brief had been given to the Secretary of Defense and the defense committees of the Congress. It was 15 view graphs presenting a basic introduction to the weapon system and the Army's conclusions. The Army evaluation asserted that:
The Patriot was successful operationally, technically and politically.
The Army had modified a system designed to kill aircraft into a successful theater ballistic missile killer.
The Patriot had intercepted all but 2 of the Scuds it engaged.
The vast majority of these interceptions resulted in killing the warhead of the Scud.
The Patriot effectiveness was almost 60 percent in Israel, almost 90 percent in Saudi Arabia and 80 percent overall.
"Effectiveness" meant the Patriot had either destroyed or dudded the warhead of the Scud (a "warhead kill"), or had knocked the Scud off course, away from the defended area (a "mission kill").
Up to that time, no one had requested to see the data that supported these claims of success.
On February 12 and 13, 1992, at the direction of the Subcommittee Chairman, a team of investigators consisting of majority and minority staff from Subcommittee, independent, nonpartisan experts from the General Accounting Office, the Congressional Research Service and the Office of Technology Assessment, carefully examined the basis for the Army's evaluation at the headquarters of the Patriot Missile Program in Huntsville, Alabama.
These two days of briefing by some two dozen Army officials and representatives from Raytheon revealed serious problems with the Army analysis of the Patriot's performance during the Gulf War. The investigators agreed that:
The Army's analysis was seriously flawed.
The Army's shot-by-shot analysis of Patriot engagements was unreliable.
The Army claims briefed to senior officials and Members of Congress since last May could not be supported by the available facts.
Much of the data in the Army analysis indicated either the Patriot missed, or the results are unknown.
The Army assessment did not contain conclusive proof that any Patriot had destroyed a Scud warhead.
Public Perceptions Were Formed Early in the Scud War
The American public's perceptions of the Patriot's success may have been formed by an event that never existed. The Army will no longer publicly discuss the first Scud interception claimed in the Gulf War. At the time, authoritative declarations of an intercept misled military experts, the media and the public. It was the first of many exaggerated claims.
The Scud attacks began on January 16, hours after U.S. forces began the bombardment of Iraq's capital city, Baghdad. Over the next two days, Iraq would launch some dozen Scuds towards Israel. The Scuds were wildly inaccurate. Most fell harmlessly into the sea or the desert. A few, however, fell in populated areas causing moderate damage and injuring people. Of these, one was a dud, its warhead recovered and carried through the streets by outraged Israeli citizens.
The psychological damage was more severe. Fear that the Scuds carried chemical warheads added to the terror of missiles streaking from hundreds of miles away, similar to the terror experienced by Londoners when German V-2 rockets slammed into their city during World War II. In this war, viewers around the world vicariously experienced some of the feeling of helplessness as they watched the air raid alerts sound and watched children in gas masks taking shelter from the attacks. This, in part, contributed to the collective sigh of relief when the Army announced that the first Iraqi Scud directed against Saudi Arabia had been shot down by an American Patriot missile.
On Friday, January 18, 1991, America awoke to an official announcement that a Patriot missile had intercepted the first Scud launched from Iraq toward American forces. Gen. Norman Schwartzkopf, Commander of the Central Command (CENTCOM) and overall commander of U.S. forces in the field, announced at a press briefing at 7:00 AM (EST) that:
"Of course, the significant news today, I'm sure you all know about, but there were seven Scuds fired early this morning against Israel, and there was one Scud missile fired against Dhahran. The one Scud missile that was fired against Dhahran was destroyed by a United States Army Patriot missile."
All morning and throughout the day, news of what seemed to be an historic first was carried on all major networks. A video tape of the event was flashed across the continents on major network news only hours after it occurred. Experts, including former military officials, were quick to add their military prestige to the reports.
General Michael Dugan, the recently retired Air Force Chief of Staff, explained to CBS Evening News anchor Dan Rather that night, "What we have seen recently is the first use of an anti-ballistic missile system in combat." He narrated a video of a Patriot climbing into the night sky:
"A Scud missile is heading towards us on the screen, You can't see it, but the Patriot's radar has detected this Scud. Here's the Patriot in slow motion. The Patriot's detected the Scud approaching and automatically alerted the operator to this threat. It asks the operator for permission to launch. He gives his consent, pushes a button and launches the Patriot to intercept and hit the Scud. And here in the clouds you can see a flash indicating the Scud was blown up."
There was not, however, a Scud "heading towards us on the screen." Nor was the public presented with any debris or evidence of a Scud. The video only showed a Patriot detonating in the clouds. There was no physical or video evidence to indicate that this Scud ever existed.
At the time, the Army claim went unchallenged. On the contrary, experts and journalists were quick to go on record in support. Stephen Myer from MIT told CBS News, "It worked very well." James Blackwell of the Center for Strategic and International Studies said on CNN that explosions on video tapes must show an intercept because there are not "any circumstances under which the warhead itself would detonate, so the bright glow is likely to be an intercept of something." This view, that the Patriot detonations in the air must be intercepts of something, would condition television interpretation of the Patriot's performance, and thus, the world's perception, throughout the war.
NBC News anchor Tom Browkow, for example, told his national audience that Patriot "is now a highly effective weapon." Using the January 18th video, reporter Katherine Couric narrated a news segment with the screen title "Missile Killer," explaining that, "Three miles above Dhahran in the early morning hours, a U.S. Patriot missile meets an Iraqi Scud missile." The report showed jubilant troops at the Patriot battery who declared, "We are the first Patriot battery in the history of the world to knock down a Scud missile." This sincere enthusiasm was infectious and the story was repeated with variations on television shows throughout the first weekend of the war.
Several stories blamed the Israelis for delaying accepting Patriot missiles for their protection. NBC's Couric, for example, cited unnamed sources who say the Israelis should have accepted U.S. offers to field Patriots sooner, since, "In its first test in battle, the Patriot passed with flying colors."
The Patriot's apparent success, along with video images of apparent success of other high-tech weapons was recognized on Wall Street. A January 18 evening news report on Boston TV station WHDH was one of many that cited the impact:
"For the Patriots manufacturer, Raytheon, the missile's performance is a major boost for morale and for the bottom line. It could mean growing sales for Raytheon, particularly on the international market. Defense stocks took off: Raytheon up 4 1/2; Martin Marietta, up 3 2/3; General Dynamics, up 4; McDonnell Douglas, up 4 1/3."
January 19-21: Patriot Appeared Perfect
On January 19, Patriot fire units were flown into Israel from U.S. forces deployed in Western Europe. Although there was also an announcement from CENTCOM that two Patriots were launched by mistake in Saudi Arabia for undisclosed "technical errors," there was a general sense of relief because, as Sam Donaldson reported from Saudi Arabia, "The Patriot missile in combat is now batting a thousand." Secretary Cheney said the United States was now offering Israel the same protection.
There were some journalistic notes of caution. CNN reported that while Pentagon spokesman claim it was an incoming Scud that was intercepted, other military officials disagree. A CNN anchor asked former assistant secretary of defense and former Raytheon executive Larry Korb to comment, noting, "The Patriot is getting a lot of good press because we do have this video tape and we have a record of it shooting down an incoming missile." Korb responded:
"This system has to operate almost out of human control...The computer determines whether, in fact, it is a real threat. It is similar to the situation we've had over the years where our strategic command at the North American Air Defense picked up false signals. That's the problem with the system as you have it. It can be easily deceived."
Korb, however, also accepted the official position at the time, and believed the Patriots would be able to handle the limited Scud threat. No one made the connections between the January 18 "interception" and the January 19 misfirings and one reported later in Turkey.
On Sunday, January 20, afternoon television was interrupted by live reports from Saudi Arabia of a second Scud attack. NBC, for example, broke into its telecast of the American Football Conference Championship to present reporter Arthur Kent from a Dhahran rooftop describing what he witnessed:
"Four Patriots, one minute apart, all in separate directions...One seemed to hug the earth. It took off straight behind us. We saw a loud flash and would assume it had intercepted a missile very close to our position. The other three took off and seemed to get lost in the sky...looking for a target, without finding one."
Kent did not know what was actually happening at the time, nor has it ever been accurately explained in public. The official view was presented by Pentagon spokesman Peter Williams later that afternoon:
"There were two launches of Iraqi Scud missiles toward Saudi Arabia...Both of the Scud missiles were destroyed, they were both intercepted. Of the five Patriots fired, three of them hit the targets--two of them hit the targets, and one of them may have hit debris. We're not certain about that. It may be that by the time the other two of the remaining five got there, there wasn't anything left to hit...It means that the Patriot is a very effective system. You heard the report earlier in the operation of an incoming target at Dhahran which was shot down by a Patriot. Here's another example. I think it indicates to us that the Patriot is a good system."
Later, Pentagon officials said there were three, not two, Scuds in the Dhahran attack. Iraq launched another Scud attack and at 8:30 Sunday night (it was already early Monday morning in Saudi Arabia), Lt. Col. Mike Gallagher briefed the press:
"We now believe ten missiles were launched, and U.S. Patriot air defense systems shot down nine of them....In the second attack, about 12:45 a.m. this morning, January 21st, Saudi time, Iraq fired seven Scud missiles--four at Riyadh, two at Dhahran, and one in the waters off Dhahran. Six of the Scuds were shot down by Patriot missiles. The Scud missile landing in the water did not require engagement. We have no reports of damage or injuries."
The Patriot's image as a miracle weapon was now firmly established. Perceptions of all future engagements would be conditioned by what people believed happened in these first encounters. Most of the information about the Patriot launches was not -- and still is not -- available to the public or the press. The official pronouncements of the Patriot's performance at the time claimed 100 percent success. Most importantly, because the Scuds caused so little damage -- comparatively -- and because people thought the Patriot's aerial detonations meant a successful intercept, the press and public thought they saw the proof of Patriot's success with their own eyes. Evidence to the contrary was neglected or dismissed.
Analysis Shows Early Claims in Saudi Arabia Incorrect
There was understandable confusion at the time. As operator reports make clear, the soldiers in the field were tense, on alert for missile attacks and most often in chemical protection garb. The Patriot units are operated by only a few troops in a small metal van called the engagement control station. The soldiers reported what they remembered seeing on the computer screen. The Patriot computers generated target information that was sometimes preserved on tape or in hard copy. Although this information is useful, it cannot irrefutable prove that the Patriot destroyed or failed to destroy the Scud warhead.
The Patriot computer console is an electronic display showing symbols sent from the Patriot computer. These projected symbols were misleading, but many of the crews could not know that at the time. They sent their impressions up the chain of command which then briefed the press.
The problem arises not with these early reports, but that Army officials and Raytheon representatives did not recognize as the engagements continued that something was wrong with their claims and correct the record. More seriously, Army officials and Raytheon executives repeated these exaggerated claims after the war despite clear evidence that the Patriot had missed.
"Patriot missiles have demonstrated the technical efficacy and strategic importance of missile defenses. This underscores the future importance of developing and deploying a system for GPALS, to defend against limited missile attacks, whatever their source....Defenses against tactical ballistic missiles work and save lives. The effectiveness of the Patriot system was proved under combat conditions."
— Vice President Dick Cheney, Senate testimony, February 21, 1991
Until the Subcommittee staff investigation, the Army had maintained that the January 18 event was a successful interception and destruction of a Scud warhead. The Patriot Selected Acquisition Report for December 31, 1991, a basic program progress report required of all major weapons systems, says: "On January 18, 1991 the first Patriot fired in combat successfully intercepted and destroyed an Iraqi Scud missile in Riyadh (sic)."
Raytheon executives repeated this claim on numerous occasions, most recently in an article published in the journal International Security, Summer 1992:
On January 18, within 24 hours of the coalition's initial air strikes, Iraqi-modified Scud tactical ballistic missiles (TBMs) were launched into civilian areas in Saudi Arabia, where force of the United States Army had been deployed with their Patriot Air Defense Systems since the previous August. On that night, Patriot achieved the first-ever wartime engagement of a ballistic missile in history, and it was successful."
Chairman John Conyers, Jr. wrote Secretary of Defense Dick Cheney about the apparent flaws in the Army analysis of this claimed success:
"The problems with the Army analysis begin with the very first Scud the Army believes it shot down on January 18, 1991. The evidence presented by the Army in support of this claim strongly indicates that a Scud was never launched. Rather, this appears to be a Patriot misfiring at a false target presented by the Patriot's computer. Two similar Patriot misfires were reported by the Army at a press briefing in Riyadh on January 19, 1991. The details of the January 18 incident are still classified, but the computer indicators lasted for only a few seconds and showed a target coming in from a highly unlikely direction. The Army had no corroborating radar, satellite or visual evidence of a Scud launch, other than the uncharacteristic computer indications. Once you examine this data I believe you will agree that it seems more likely that this was a computer glitch than a phantom Scud."
The Army will no longer publicly discuss this claimed interception.
This incident and the claims made by the Army and Raytheon about it, demonstrated several important flaws in the Army assessment that reappeared throughout the report and raised serious doubts about the reliability of the evidence presented in support of claims of warhead kills.
Early Claims in Israel Also Incorrect
On January 22, officials announced that Patriot missiles had intercepted the first Scud missile launched against Israel since the Patriot had been deployed. They were wrong.
High-ranking Israeli military officers had gathered in the underground command center of the Israeli Air Force on January 22 as air raid sirens warned of a Scud attack. An Israeli journal described what happened next:
"Until that night, the 22nd of January, Israel had already absorbed eleven missiles. The terror generated from possible chemical attack was still in the air, and feelings were low and the sense of frustration was high. The Patriot battery in the north of Tel Aviv was now going to be the final answer to the Scud missiles. On the screen in the shelter in the command center, a hit was announced, and some of the staff began to look for a bottle of champagne...
"A few minutes after that, preliminary information began to arrive on the falling of the Scud on Aba Hillel street, in Ramat-Gan, and as the hours passed there were streams of disquieting reports from the field. At the end of the war it would be concluded that this particular Scud was the most lethal of all. One dead woman, ninety-seven wounded, a ruined apartment building, heavy damage in twenty nearby building, and blast damage for a radius of 300 meters...
"It was now clear that a hit of a Scud by a Patriot did not mean an interception."
Scuds Proved a Difficult and Complex Target
The exaggerated claims made during the early days of the war were caused, in part, by the unexpected behavior of the Iraqi Scud missiles as they reentered the atmosphere.
The Scud was designed to fly about 300 kilometers. To increase the range, Iraqi engineered lengthened the missile and lightened the warhead. This did increase the range to about 600 kilometers, but it had the unintended effect of destabilizing the missile in flight.
The launch carries the Scud out of the atmosphere into a brief flight in space. It peaks at about 100 kilometers altitude and then falls back towards earth. As it reenters, the nose of the Scuds, instead of pointing downwards, were often too light and thus the missile hit the air flat, like a paper airplane without a paper clip to keep it aerodynamic. The resulting stress tore the missile apart. It would disintegrate, sometimes in great fiery tumbles, sometimes streaking like a comet with pieces trailing behind.
The Patriot computer misinterpreted this break-up. It depicted on its screen not one but two, three or a dozen Scuds streaking in towards the Patriot fire unit. As Raytheon executive Robert Stein explains:
"Upon reentry, the resulting forces caused the missile to break apart into several pieces. These extra pieces looked to the Patriot software like targets that were diving at high speed and were going to impact in the areas that the defense design was laid out to defend. In effect, they became 'decoys' that were indistinguishable from TBMs to the Patriot radar, since no discriminations features had been implemented in anticipation of these types of targets.
"The anomalous behavior that the operators were seeing was created by the aerodynamic instability of the warhead section after the missile started to break up. It was spiraling, rather than travelling on an expected ballistic trajectory, because of changes in its center of gravity and center of aerodynamic pressure after breakup. In addition, its radar reflectivity had dropped significantly because of its smaller size. In effect, what Iraqi engineers had created, purely unintentionally and by poor workmanship and design, was a high-speed, low radar-cross-section, maneuvering reentry vehicle (RV), accompanied by decoys...its accuracy was very poor..."
Eventually Israeli and U.S. analysts recognized this problem and efforts to correct the software were rushed into the field in early February. In the first week of Scud attacks, however, this phenomenon contributed to confusions and exaggerated claims of success from Patriot operators. Coupled with poor or no efforts to assess ground damage in Saudi Arabia, it led them to believe erroneously that they were phenomenally successful in shooting down Scuds.
Half of all Patriot-Scud engagements took place during this first week. During the war, the Army believes that almost half of the 158 Patriots were launched at what the Army now believes were false targets and debris (15 percent at false targets, 30 percent at Scud debris).
This confusing situation may be interpreted in various ways. Going back over the engagements, the analysts from the Army and Raytheon now believe they can distinguish the real Scud warheads from the debris in most instances. In these cases, they often claim that a Patriot hit the Scud, causing the debris to appear, or that while some Patriots did hit debris, others hit the warhead. These claims rest on two principle sources of data: "probable kill" indicators and ground damage reports. Neither is reliable evidence, as described later in this report.
Unpredictable Impact Points
As part of the Army assessment, evaluators also projected Scud impact points based on the recorded tracking data. These projections assumed a smooth ballistic trajectory. If the predicted impact point was in a populated area and the Army then had no damage reports, the evaluators assess this as high confidence evidence that the Patriot must have destroyed the Scud warhead.
As Mr. Stein notes, however, the spontaneous disintegration of the Scuds also meant that Scuds often did not follow smooth, predictable flight paths. They would often violently change speed and direction as they descended. This raises serious questions about the accuracy of the predicted impact points. If the predicted impact point was projected based on minimum data, as was sometimes the case, it could produce an inaccurate prediction of impact. In other words, two readings taken from one part of a spiral could produce a straight line to a predicted impact point, when, in fact, the Scud could have spiraled away into a less populated area, the desert or the sea, thus reducing the likelihood that any damage would be reported.
Conclusion
The GAO found that only 9 percent of the warhead kills claimed by the Army were supported by the strongest evidence that an engagement resulted in a warhead kill.
"For example, the strongest evidence that a warhead kill occurred would be provided by (1) a disabled Scud with Patriot fragments or fragment holes in its guidance and fuzing section or (2) radar data showing evidence of Scud debris in the air following a Patriot detonation."
Serious questions may be raised about even these few claims. The Army did not have evidence of any scientific analysis performed on a Scud warhead to determine whether, in fact the marks found on the Scud warheads were caused by Patriot fragments or by ground impact or by detonation. These assertions are based in each case on the opinion of a single individual, sometimes recorded months after the event. In one case, they are based on the opinion of a Patriot Program Office official who told GAO he had seen a classified photo of a warhead and in his opinion the damage could only have been caused by a Patriot. He refused to show the photo to the GAO on the grounds that it was too highly classified, a claim that later proved to be incorrect.
Moreover, some Scuds that were not engaged by Patriots exhibited characteristics identical to those cited as evidence of Patriot interceptions. The Scuds flew in at high speeds, broke up into debris, and upon impact the warheads were found to be duds or only partially burned. In cases where Patriots had attempted to intercept such a Scud, this behavior would be cited as crucial evidence in scoring the engagement as a successful kill.
It is possible that Patriot missiles did kill more than a few Scud warheads, but it is difficult to have much confidence in that possibility.
A compliant media, deceptive federal agencies, and profiteering industries are an all too frequent reality. We have to hope that today’s reports on the “New Patriots” are more factual.
This was a fascinating look into the not so distant past .