Words have meaning: Anomaly
In these posts, I typically like to highlight words with very specific meanings that are used far too generally or improperly by the average person. However, the popularity of my Norway Spiral post has led me to another word, one which is used as a catchall by engineers. And a word that seems to imply much, while actually giving nearly zero information. I mean, of course:
In engineer-speak, an “anomaly” is anything that didn’t go the way you expected it to go. While we test this hardware over and over on the ground, and rehearse the expected launch and activation sequences repeatedly, sometimes things just don’t behave as you expect. This can be due to something catastrophic, like a mission-ending hardware failure, or something as simple as not getting telemetry when you expected. (This can happen due to a scheduling conflict giving access to the communication satellite you were planning to use to a different, higher priority, user.)
When things don’t work the way you expect, it must ALWAYS be documented (an issue/discrepancy/anomaly/pick-a-word report should be filed). If the reason for the anomaly is simple, this step is a formality. But good engineering practices means it should be done anyway. On the other hand, some anomalies, especially those that result in mission loss, will be investigated by a number of experts for as long as it takes to either 1) find the root cause and communicate it to the rest of the space industry, or 2) determine that the cause is unknowable due to lack of sufficient information.
The Columbia tragedy started out as an anomaly and was investigated for years, leading to significantly improved processes for monitoring orbiter health post-launch. And you can bet the Norway Spiral was a launch vehicle anomaly. We watch this video and chuckle at the network callout that “we have just had an anomaly…” True, that may seem like a gross understatement. But in an industry where words have very specific meanings, no other word can be used without implying more than simply “something didn’t behave as expected.”
So next time you hear about some “anomaly” occurring on your favorite spacecraft, remember: it could be anything…or nothing at all.