The Guardian has released a new set of puzzles today, designed to test engineering knowledge. The challenges include scenarios such as cranberry sorting, medicine bottle cap design, and the unintended consequences of a Golden Gate Bridge handrail replacement.
One puzzle also delves into how UK manufacturer de Havilland pressure-tested its Comet plane in the early 1950s, following major plane crashes caused by fuselages ripping apart mid-flight.
These puzzles are adapted from a new book titled 'How to Keep a Plane in the Sky', written by technology reporter Alex Davies. The book explores the work of scientists behind the reliability of objects.
The puzzle setter, who has been publishing puzzles on alternate Mondays since 2015, recently received the 2026 Christopher Zeeman Medal. This award is the UK’s most prestigious honour for mathematics communication, presented by the London Mathematical Society and the Institute for Mathematics and Its Applications.