1. Ariane 5 rocket lost due to software glitch.
On June 4 1996, the European Space Agency test-launched the Ariane 5 rocket. A bug in the control software, written in the programming language Ada, caused the rocket to self-destruct 37 seconds after blast-off.
See Ariane disaster:
Its conclusion: the explosion was the result of a software error -- possibly the costliest in history (at least in dollar terms, since earlier cases have caused loss of life).
Particularly vexing is the realization that the error came from a piece of the software that was not needed during the crash. It has to do with the Inertial Reference System, for which we will keep the acronym SRI used in the report, if only to avoid the unpleasant connotation that the reverse acronym could evoke for US readers. Before lift-off certain computations are performed to align the SRI. Normally they should be stopped at -9 seconds, but in the unlikely event of a hold in the countdown resetting the SRI could, at least in earlier versions of Ariane, take several hours; so the computation continues for 50 seconds after the start of flight mode -- well into the flight period. After takeoff, of course, this computation is useless; but in the Ariane 5 flight it caused an exception, which was not caught and -- boom.
The exception was due to a floating-point error: a conversion from a 64-bit integer to a 16-bit signed integer, which should only have been applied to a number less than 2^15, was erroneously applied to a greater number, representing the "horizontal bias" of the flight. There was no explicit exception handler to catch the exception, so it followed the usual fate of uncaught exceptions and crashed the entire software, hence the on-board computers, hence the mission.
2. Investment firm Knight Capital nearly went into bankruptcy due to software glitch.
A computer glitch nearly pushed investment firm Knight Capital into bankruptcy. The firm lost half a billion dollars in half an hour when a software error allowed computers to buy and sell millions of shares with no human oversight. The company's stock prices plunged by about 75 per cent in two days.
See Knight nearly bancrupt after software glitch
On 1 August 2012, an installation problem in Knight Capital’s software blasted out a gusher of erroneous stock trade orders. After trading out of all those errors, Knight suffered a pre-tax loss of about US $440m. That’s an Olympic-sized loss that happened almost as fast as a star athlete’s stumble in London.
3. The north-east US power outage back in 2003 was caused by software glitch.
The 2003 North America blackout, at the time the second most widespread power outage in history, was the result of a local blackout that went undetected by General Electric software then cascaded out of control.See General Electric software glitch:
On August 14, 2003, shortly after 2 P.M. Eastern Daylight Time, a high-voltage power line in northern Ohio brushed against some overgrown trees and shut down—a fault, as it's known in the power industry. The line had softened under the heat of the high current coursing through it. Normally, the problem would have tripped an alarm in the control room of FirstEnergy Corporation, an Ohio-based utility company, but the alarm system failed.
Over the next hour and a half, as system operators tried to understand what was happening, three other lines sagged into trees and switched off, forcing other power lines to shoulder an extra burden. Overtaxed, they cut out by 4:05 P.M., tripping a cascade of failures throughout southeastern Canada and eight northeastern states.
All told, 50 million people lost power for up to two days in the biggest blackout in North American history. The event contributed to at least 11 deaths and cost an estimated $6 billion.
