It was only a typo, it was only a typo!

by William O'Grady for Blog
It was only a typo, it was only a typo!

We all make mistakes – it happens. Luckily for most of us, these mistakes may only result in a minor inconvenience. From getting your “There, Their, They’re” mixed up, to forgetting to include punctuation; typos are a fact of life.  In programming a typo can happen as easily as a slip of the finger. Such slips are easily caught thanks to an IDE such as Microsoft Visual Studio.  Even if something slips through, what’s the worst that can happen…

A lot can happen, actually! Spare a thought for the programmers who made the following simple, yet incredibly costly mistakes.


Aliens: Colonial Marine


In 2013, the video game Aliens: Colonial Marine was released to widespread ridicule. Despite high hopes, the game was found to be practically unplayable with noticeably glitchy AI.

In October of 2017, a possible reason for the glitches was discovered – a single misspelt word. A typo was found in the game’s configuration file. A word should have spelt “AttachPawnToTether” but had instead been spelt “AttachPawnToTeather”. This caused the enemy Aliens to have no understanding of where they were in the game. They would randomly appear or not react to the player at all.  Despite strong initial sales, the game ultimately flopped. Poor reviews and online scores saw to this. But for a single letter change, Aliens: Colonial Marine may have had a completely different fate.


Mariner 1


Launched in 1962, Mariner 1’s mission was to survey the planet Venus. At a cost of approximately £380 million in today’s money, its downfall was partially caused by one of the most expensive typographical errors in history.  Shortly after take-off, Mariner 1 went sharply off course. Alarmed by its trajectory, NASA decided to hit the self-destruct button. Reports at the time stated that a misplaced hyphen caused an error in the guidance system.

While the “most expensive hyphen in history” has been widely reported as the reason behind the failure, NASA have since announced that this was just one of many bugs. Nonetheless, Mariner 1’s 5-minute flight was a serious blow to NASA’s reputation during the Space Race.


Ariadne 5


In June 1996, it was the turn of the European Space Agency (ESA) to rue software errors. The ESA were planning on launching a group of spacecrafts called Cluster, using the brand-new Ariadne 5 rocket. On its maiden flight, a catastrophic system failure lead to the self-destruction of the rocket and its payload.

Ariadne 5 had been designed to use much of the Ariadne 4 computer systems. However, the faster engines exploited a previously unknown error. They had failed to protect against integer overflow. The system had tried to force a 64-bit integer into a 16-bit space. This overflow caused a complete system shut down and lead to an expensive blot in the ESA’s copybook. A software handler that could have dealt with the problem had been disabled, and so there was no levee to dam the cascade of system failures that led to the destruction of the thankfully unmanned spacecraft.


Let these events serve as a reminder for the importance of proof-reading. Now go and review that code you’re working on before you publish it!

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