The Federal Aviation Administration has opened an investigation into potential structural issues with hundreds of Boeing 737 jets after an incident involving Southwest Jets, according to the Wall Street Journal. On Monday, an inflight incident on a flight from Las Vegas to Boise, Idaho, left a 12-inch rupture in the aircraft‘s aluminum skin. Nobody was hurt in the incident and the flight landed safely at the final destination but the plane’s cabin gradually lost pressure, although not to the extent to trigger oxygen masks. The event has prompted the FAA to look at a number of 737 aircraft to study the integrity of the same part of the fuselage. This analysis is not related to earlier problems with Boeing’s 737 MAX.