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>I'm sure in 1998 there was a similar utility such as units; still the Mars Climate Orbiter disaster The utility did exist then, but a reading of the mishap re

>I'm sure in 1998 there was a similar utility such as units; still the Mars Climate Orbiter disaster The utility did exist then, but a reading of the mishap report[0] for that event makes it clear that NASA was not using it. It looks like someone assigned a constant using the Imperial measure rather than Metric representation of a value. The function that used this constant did not verify the unit of measure, and the constant was likely just a floating point number, not a data type that even stored unit of measure. I haven't read the Gimli report yet, but it's probably the same story: human error. Edit: The Gimli Glider [1] was caused by human error. [0] ftp://ftp.hq.nasa.gov/pub/pao/reports/1999/MCO_report.pdf see page 16 [1] http://aviation-safety.net/database/record.php?id=19830723-0 http://aviation-safety.net/database/record.php?id=19830723-0

mpweiher 11y ago
> probably the same story: human error. Right. Humans are error-prone. That's why you want to remove places where human can make errors, such as unnecessary unit conversions.
- garrettgrimsley 11y ago
  I agree, and I don't mean to argue against moving to the metric system. I only intended to dispel the notion that software safeguards that would have prevented these incidents were in place and failed. Educating developers about this potential issue and ensuring safeguards are in place to prevent disaster seems like a more readily achievable goal than inducing a national migration to the metric system.
  - Ntrails 11y ago
    Sod national, I'm talking about corporate. If my company mandates that all code must be written in Lisp, then that's what I'll do. If they mandate all monetary values must be stored as USD then that's what I'll do. And if they require that all code must use the metric system - with display options to convert to imperial? Thats. What. I'll. Do. I don't care what the coding guidelines are - I only care that they exist. [within reason]
- zeveb 11y ago
  In aviation the standard units are traditional units; it's the French units which are non-standard and unnecessary. So the Right Answer is to switch to traditional units everywhere:-)

mpweiher 11y ago

> probably the same story: human error. Right. Humans are error-prone. That's why you want to remove places where human can make errors, such as unnecessary unit conversions.

garrettgrimsley 11y ago
I agree, and I don't mean to argue against moving to the metric system. I only intended to dispel the notion that software safeguards that would have prevented these incidents were in place and failed. Educating developers about this potential issue and ensuring safeguards are in place to prevent disaster seems like a more readily achievable goal than inducing a national migration to the metric system.
- Ntrails 11y ago
  Sod national, I'm talking about corporate. If my company mandates that all code must be written in Lisp, then that's what I'll do. If they mandate all monetary values must be stored as USD then that's what I'll do. And if they require that all code must use the metric system - with display options to convert to imperial? Thats. What. I'll. Do. I don't care what the coding guidelines are - I only care that they exist. [within reason]
zeveb 11y ago
In aviation the standard units are traditional units; it's the French units which are non-standard and unnecessary. So the Right Answer is to switch to traditional units everywhere:-)