In this week’s Flightless Bird, David Farrier sets out to understand why Americans say “math”, while New Zealand - and most of the rest of the world - says “maths”. He speaks to Dean Koorey about the mysteries of language, before stumbling into the depths of math/maths and the perils of the metric system. How many ounces in a pound? How many pounds are in a stone? And why is America stuck using the imperial system when the rest of the planet loves the sensible metric system? Farrier is shocked to find that NASA once lost a space probe thanks to a metric conversion disaster, and meets with aerospace engineer Omar Abed to get to the bottom of the mess.