A much better article on this topic: <a href="https://www.nist.gov/pml/us-surveyfoot" rel="nofollow">https://www.nist.gov/pml/us-surveyfoot</a><p>nytimes slogs through boring narrative before describing the actual definitions of the two types of foot.
> The two feet differ by about one hundredth of a foot (0.12672 inches) per mile [...]<p>> In one case, in a certain city that Dr. Dennis declined to name, the construction of a downtown high-rise that sat in the approach path to an international airport was delayed while the building was redesigned to be one floor shorter.<p>How could that make sense? Seems like an absurd claim to blame the difference in measurement. There had to be some design buffer to stay under the height limit so other errors had to dominate. It's a curious situation but I suspect not nearly as critical as presented. We don't do rocket science or engineer medical devices in US survey inches.