A Ryanair Boeing 737-800, flight FR5448 from Seville to Nantes, declared a Mayday Fuel emergency mid-air after an Iberia CRJ-1000 suffered engine failure during takeoff, blocking Nantes-Atlantique’s single runway and forcing a go-around. With fuel reserves critically depleted following the unplanned diversion, the captain squawked 7700 and received priority vectoring to Brest Bretagne Airport, 150 miles northwest, where the aircraft landed safely 2 hours and 40 minutes after departure. The runway closure lasted four hours, disrupting five inbound and six outbound flights, while debris from a ruptured tire caused the Iberia jet’s engine shutdown. No injuries occurred, and Ryanair confirmed fuel levels remained above final reserve upon landing at Brest.