Patriot missile defense software problem led to system failure at dhahran

A report of the government accountability office entitled patriot missile defense. Software problem led to system failure at dhahran, saudi arabia it is report number gaoimtec9226, dated february 1992. Patriot missile batteries and the dangers of software errors. The fallacy of proven and adaptable defenses federation of. This paper focuses on the issues that lead to the failure at dhahran and on possible approaches for the prevention of these issues. A report of the general accounting office, gaoimtec9226 a,20 entitled patriot missile defense. Software problem led to system failure at dhahran, saudi arabia general accounting office washington dc information management and technology div on february 25, 1991, a patriot missile defense system operating at dhahran, saudi arabia, during operation desert storm failed to track and intercept an incoming scud. S300mpu and s300 v videos page 3 sino defence forum. I acquired a copy of the report and found it to be very interesting from a numerical analysis perspective. Software problem led to system failure at dhahran, saudi arabia reported on the cause of the failure.

The particular incident you listed is really quite an extraordinary circumstance. Background the patriot is an army surface to air, mobile, air defense missile system. Specifically, the time in tenths of a second, as measured by the systems. The computer failure that blinded a patriot missile defense system to an iraqi missile that killed 28 americans during the persian gulf war was similar to a problem discovered in another patriot. Results in brief the patriot battery at dhahran failed to track and intercept the scud mis sile because of a software problem in the systems weapons control com puter. Patriot missile defense software problems led to systems failure at dhahran, saudi arabia, gao report february, 1992, b247094. Round off errors and the patriot missile the numerical. Causal analysis of the 1991 patriot missile system failure. Software problem led to system failure at dhahran, saudi arabia, gaoimtec92 26, february 1992. The scud struck an american army barracks, killing 28 soldiers and injuring around 100 other people. Since the mid1960s, the system has evolved to defend against aircraft and cruise missiles, and more recently against shortrange ballistic missiles. Background the patriot is an army surfacetoair, mobile, air defense missile system. There is a nice concise writeup of the problem, with a prefatory background on how the patriot system is designed to work, in the official postfailure analysis report by the u. Sep 06, 2010 the software error wiki alludes to is that the patriot missile kept track of its internal clock with floating point numbers.

Technically this would be described as a requirements failure. Mar 28, 2018 us patriot missile defense system malfunctions, crashes in saudi arabias capital. It turns out that the cause was an inaccurate calculation of the time since boot due to computer arithmetic errors. The hindsight explanation of this tragedy consists of the following. On february 25, 1991 a patriot missile battery failed to intercept an incoming scud missile aimed at an army barracks in dhahran, saudi arabia. Too bad the patriot cant shoot down an obsolete seersucker that hit kuwait city getting past awacs, aegis, and patriot sensors without being seen. Imtec9226 paperback pdf our solutions was launched with a wish to work as a full on the web digital collection which offers use of. But, as is the case in any failure of a complex system, many factors may have contributed to the failure of the patriot missile. The iraqi missile impacted into an army barracks, killing 28. Section 2 gives a brief summary about the events around the incident at dhahran. Patriot missile software problem unc computer science. The scud struck an american army barracks and killed 28 soldiers. This problem led to an inaccurate tracking calculation that became worse the longer the.

The report is quite well done and includes pictures that show the exact process used to track a scud. A report of the general accounting office, gaoimtec9226, entitled patriot missile defense. On february 25, 1991, a patriot missile defense system operating at dhahran, saudi arabia, during operation desert storm failed to track and intercept an incoming scud. The patriot defense system had failed to track and intercept the scud. Included in this report is prefatory background on how the patriot system is designed to work. During that night a patriot missile defence system operating in dhahran.

The patriot battery at dhahran failed to track and intercept the scud missile because of a software problem in the systems weapons control computer. Officers examining an r17 missile shot down by a patriot mim104 sam system in the desert during operation desert storm. Results in brief the patriot battery at dhahran failed to track and intercept the scud mis sile because of a software problem in the system s weapons control com puter. This paper focuses on the issues that lead to the failure at dhahran and. And intercepting a burkan2h with a patriot missile is a vastly different problem than the question of. At the time of the incident, the battery had been operating continuously for over 100 hours. Software problem led to system failure at dhahran, saudi. Dec 04, 2017 it was a victory for the saudis and for the united states, which supplied the patriot missile defense system.

Patriot missile a report of the general accounting office, gaoimtec9226, entitled patriot missile defense. Software problem led to system failure at dhahran, saudi arabia gao id. Round off errors and the patriot missile t wentyeight americans were killed on february 25, 1991 when an iraqi scud hit the army barracks in dhahran, saudi arabia. On february 25, 1991, a patriot missile defense system operating at dhahran, saudi arabia, during operation desert storm failed to track and intercept an. The patriot was the first air defense system in the world to successfully intercept a theater ballistic missile. Mar 30, 2018 the patriot missile program was developed by the us missile defense agency, which transferred operation to the us army in 2003. Software problem led to system failure 20 at dhahran, saudi arabia reported on the cause of the failure. Justia gao reports imtec9226 patriot missile defense. Software problem led to system failure at dhahran, saudi arabia general accounting office washington dc information management and technology di on. Jun 02, 2008 patriot missile defense software problem led to system failure at dhahran, saudi arabia, gao report, general accounting office, washington dc, february 4, 1992. Software problem led to system failure at dhahran, saudi arabia jan 1992 1919219218. Details flaw in patriot missile the new york times.

Report gaoimtec9226, information management and technology. On the dhahran scud, see general accounting office, patriot missile defense. Ships more air defense systems that do not work to. Software problem led to system failure at dhahan, saudi arabia, washington, d. It turns20 out that the cause was an inaccurate calculation of the time since boot due to20 computer arithmetic errors. The mim104 patriot is a surface to air missile sam system, the primary of its kind used by the united states army and several allied nations. On february 25, 1991, a patriot missile defense system operating at dhahran, saudi arabia, during operation desert storm failed to track and. The patriot missile failure in dharan, saudi arabia, on february 25, 1991 which. The computer failure that blinded a patriot missile defense system to an. This scud subsequently hit an army barracks, killing 28 americans. Us patriot missile defense system malfunctions, crashes in.

Imtec9226 february 4, 1992 because of a software problem in the patriot missile defense system, the patriot battery at dhahran, saudi arabia, failed to track and intercept an incoming iraqi scud missile that later struck an army barracks, killing 28 americans. It tells me that the people who were designing this software really had no idea of how numbers are stored. Data does not exist to conclusively say how well patriot performed report by general accounting office, september 1992, b250335. Patriot missile defense software problem led to system failure at dhahran, saudi arabia, gao report, general accounting office, washington dc, february 4, 1992. Software problem led to system failure at dhahran, saudi arabia. Led to system failure at dhahran, saudi arabia provides a nice concise writeup of the problem. Example of a disaster caused by subtractive cancellation. Patriot missile software failure, 28 soldiers died. An attack in saudi arabia shows raytheons patriot missile. It turns out that the cause was an inaccurate calculation of the time since boot due.

Page 1 gaoamtec9226 patriot missile software problem. The patriot missile battery at dhahran had been in operation for 100 hours, by which time the systems internal clock had drifted by onethird of a second. Us air defenses en route to saudi arent up to the job. But further investigations determined that the scud was intact when it hit the barracks, and was not detected because the patriot s radar system was rendered inoperable by the computer failure. On february 25, 1991, a patriot missile defense system operating at. Im actually a software engineer, thats why i got interested in the patriot missile and control software of planes. Patriot missile defensesoftware problem led to system failure at dhahran, saudi arabia, march 1992. The patriot battery at dhahran failed to track and intercept the scud missile because of a software problem in the system s weapons control computer. General accounting office gao imtec9226 entitled patriot missile defense. The official post failure analysis report by the u. Patriot missle bug report a government report on the failure of the patriot missile is available. When the machine had been booted in the recent past, such as every time in testing, the floating point number spent most of its precision to the right of the decimal point.

Section 1 explains what the patriot system is and how it works. Due to the failure of the equipment, the missile hit an army barracks and killed 28 americans. A government investigation revealed that the failed intercept at dhahran had been caused by a software error in the systems handling of timestamps. Mtriot missile software problem led dhahran, saudi arabia. Citeseerx scientific documents that cite the following paper. When the scud missile hit the barracks 28 soldiers lost their lives and 99 were wounded. Software problem led to system failure at dhahran, saudi arabia provides a nice concise writeup of the problem. Eventually, the army attributed the patriot missile failure in dhahran to a software failure in the computer as a result of long use of the radar system u. This problem led to an inaccurate tracking calculation that became worse the longer the system operated. Software problems led to system failure at dhahran, saudi arabia.