1) - Mars
Climate Orbiter Crashes (1998)
A sub-contractor
who designed the navigation system on the orbiter used imperial units of
measurement instead of the metric system that was specified by NASA.
Result - The $125
million dollar space craft attempted to stabilize its orbit too low in the
Martian atmosphere, and crashed into the red planet.
2) -
Mariner I space probe (1962)
While transcribing a handwritten formula into
navigation computer code, a programmer missing a single superscript bar. This
single omission caused the navigation computer to treat normal variations as
serious errors, causing it to wildly overreact with corrections during launch.
To be fair to the programmer, the original formula was written in pencil on a
single piece notebook paper - not exactly the best system for transcribing
mission critical information. Then again, this was 1962…
Result - 237 seconds into the mission that was supposed to send Mariner I
to Venus, the space craft was so far off course that Mission Control had to
destroy it over the Atlantic. The cost of the spacecraft was $18.2 million in
1962.
3) -
Ariane 5 Flight 501 (1996)
NASA
certainly isn’t alone in its spacecraft destroying software bugs though. In
1996, Europe’s newest unmanned satellite-launching rocket, the Ariane 5, reused
working software from its predecessor, the Ariane 4. Unfortunately, the Ariane
5’s faster engines exploited a bug that was not realized in previous models. In
essence, the software tried to cram a 64-bit number into a 16-bit space. The
resulting overflow conditions crashed both the primary and backup computers (which
were both running the exact same software).
Result - 36.7 seconds
into its maiden launch, the self-destruct safety mechanism was activated due to
the computer failures, and the spacecraft disintegrated in a spectacular
fireball. The Ariane 5 had cost nearly $8 billion to develop, and was carrying
a $500 million satellite payload when it exploded.
4) - EDS Fails Child Support (2004)
In
2004, ED’s software giant introduced a large, complex IT system to the U.K.’s
Child Support Agency (CSA). At the exact same time, the Department for Work and
Pensions (DWP) decided to restructure the entire agency. The restructure and
the new software were completely incompatible, and irreversible errors were
introduced as a result. With over 500 bugs still reported as open in the new
system, the clash of the two events has crippled the CSA’s network.
Result - The system
somehow managed to overpay 1.9 million people, underpay another 700,000, had $7
billion in uncollected child support payments, a backlog of 239,000 cases,
36,000 new cases “stuck” in the system, and has cost the UK taxpayers over $1
billion to date.
5) - Soviet Gas Pipeline Explosion (1982)
When
the CIA (allegedly) discovered that the Soviet Union was (allegedly) trying to
steal sensitive U.S. technology for its operation of their trans-Siberian
pipeline, CIA operatives (allegedly) introduced a bug into the Canadian built
system that would pass Soviet inspection but fail when in operation.
Result - The largest non-nuclear
explosion in the planet’s history. And a new-found respect (fear?) of the CIA.
6) - Black Monday (1987).
On
October 19, 1987, a long running bull market was halted by a rash of SEC
investigations of insider trading. At the time, computer trading models were
(and still are) common in the trading market, and most had triggers in place to
sell stocks if their value dropped to a certain point. As investors began to
dump stocks affected by the investigations, their stocks dropped, causing the
computer triggers to kick in. The flood of computer issued stock executions,
coupled with investor liquidation, overwhelmed the market and caused multiple
systems to crash. This in turn triggered even more automated sell executions,
and panic quickly set in. Investors were selling blind world-wide, stocks were
virtually liquidated, and market values plummeted.
Result - Technically beginning in Hong Kong (where markets opened first),
the crash had world-wide implications. The impact in the US was devastating. The
Dow Jones Industrial Average plummeted 508 points, losing 22.6% of its total
value. The S&P 500 dropped 20.4%. This was the greatest loss Wall Street
ever suffered in a single day.
7) - Therac-25 Medical Accelerator (1985)
The
Therac-25 was a radiation therapy device built by Atomic Energy of Canada
Limited (AECL) and CGR of France. It could deliver two different kinds of
radiation therapy: either a low-power electron beam (beta particles) or X-rays.
Unfortunately, the operating system used by the Therac-25 was designed and
built by a programmer who had no formal training. The OS contained a subtle
race condition, and because of it a technician could accidentally configure the
Therac-25 so the electron beam would fire in high-power mode without the proper
patient shielding.
Result - In at least 6 incidents (with more suspected), patients were
accidentally administered lethal or near lethal doses of radiation -
approximately 100 times the intended dose. At least five deaths are directly
attributed to it, with others seriously injured.
8) - Multidata Systems (2000)
Another medical system makes the list, this
time at the National Cancer Institute in Panama City. This one is a combination
of software bug as well as user error. A U.S. firm, Multi data Systems
International, created therapy planning software that was designed to calculate
the proper dosage of radiation for patients undergoing radiation therapy. The
software allows a radiation specialist to draw on their screen where they would
be placing metal shields (called “blocks") on the patient during
treatment. These blocks protect healthy tissue from the radiation. The software
itself only allows the placement of 4 blocks, but the Panamanian doctors
normally used five. To get past the limitation in the software, the doctors
decided to trick the software by drawing all five blocks as a single block with
a hole in the middle. Unfortunately, a bug in the Multi data software caused it
to give different results depending on how the hole was drawn. Draw it one way
and the dosage was correct. Draw it in the other direction and the software
recommended twice the correct dosage.
Result - At least
eight patients die, while another 20 receive overdoses likely to cause
significant health problems. The physicians, who were legally required to
double-check the computer’s calculations by hand, are indicted for murder.
9) - Patriot Missile Bug (1991)
During the first Gulf War, an American Patriot
Missile system was deployed to protect US Troops, allies, and Saudi and Israeli
civilians from Iraqi SCUD missile attacks. A software rounding error in the one
of the early versions of the system incorrectly calculated the time, causing it
to ignore some of the incoming targets.
Result - A Patriot Missile Battery in Saudi Arabia fails to intercept an
incoming Iraqi SCUD. The missile destroyed an American Army barracks, killing
28 soldiers and injuring around 100 other people.
10)
- World War III… Almost (1983)
Have
you ever seen the movie War Game? Nobody knew at the time how very close this
movie mimicked a real life near-disaster in the same year. In 1983, Soviet
early warning satellites picked up sunlight reflections off cloud-tops and
mistakenly interpreted them as missile launches in the United States. Software
was in place to filter out false missile detections of this very nature, but a
bug in the software let the alerts through anyway. The Russian system instantly
sent priority messages up saying that the United States had launched five
ballistic missiles. Protocol in such an event was to respond decisively,
launching the entire soviet nuclear arsenal before any US missile detonations
could disable their response capability. The duty officer for the system, one
Lt Col Stain’s lave Petro, intercepted the messages and flagged them as faulty,
stopping the near-apocalypse. He claimed that he had a “funny feeling in my
gut” about the attack, and reasoned if the U.S. was really attacking they would
launch more than five missiles.
Result - Thankfully
nothing. However, the world was literally minutes away from “Global Thermal
Nuclear War”. Any retaliatory missile launched by the Soviets would have
triggered a like response from the U.S., eventually leading to a total launch
of all systems from both sides.
Post by :- Hemangini
Published by :- Pardha Saradhi
Post by :- Hemangini
Published by :- Pardha Saradhi
