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Metric mania

1. The Gimli Glider

The subsequent investigation revealed a combination of company failures and a chain of human errors that defeated built-in safeguards. The amount of fuel that had been loaded was miscalculated because of a confusion as to the calculation of the weight of fuel using the metric system, which had recently replaced the English (imperial) system for use with the 767.

https://en.wikipedia.org/wiki/Gimli_Glider

2. Mars Climate Orbiter

The whole thing could be written off as a miscommunication. Propulsion engineers, like those at Lockheed Martin who built the craft, typically express force in pounds, but it was standard practice to convert to newtons for space missions. One pound of force is about 4.45 newtons. Engineers at NASA’s Jet Propulsion Lab assumed the conversion had been made, and didn’t check.

_ excerpted from “Metric math mistake muffed mars mission”, Wired magazine, Lisa Grossman

Learning Standards

Massachusetts Science and Technology/Engineering Curriculum Framework
Science and Engineering Practices: 5. Using Mathematics and Computational Thinking:
Apply ratios, rates, percentages, and unit conversions in the context of complicated measurement problems involving quantities with derived or compound units (such as mg/mL, kg/m 3, acre-feet, etc.).

National Council of Teachers of Mathematics
Students need to develop an understanding of metric units and their relationships, as well as fluency in applying the metric system to real-world situations. Because some non-metric units of measure are common in particular contexts, students need to develop familiarity with multiple systems of measure, including metric and customary systems and their relationships.

National Science Teachers Association
The efficiency and effectiveness of the metric system has long been evident to scientists, engineers, and educators. Because the metric system is used in all industrial nations except the United States, it is the position of the National Science Teachers Association that the International System of Units (SI) and its language be incorporated as an integral part of the education of children at all levels of their schooling.