On April 15th 2018, CBS News 60 MINUTES featured a two-part investigation into the safety record of one of the country's most profitable airlines, Allegiant Air, a small, ultra-low-cost carrier based in Las Vegas. Over the course of seven months, correspondent Steve Kroft and his producers analyzed hundreds of federal aviation documents and interviewed pilots, mechanics and industry experts for a report that raised disturbing questions about the safety of Allegiant's fleet. Although Allegiant flies less than 100 planes, our investigation found that over a 20-month period, the airline experienced over 100 serious mechanical problems, including mid-air engine failures, cabin depressurization, smoke in the cabin, flight control malfunctions, hydraulic leaks and aborted take-offs. The incidents forced Allegiant pilots to declare 46 in-flight emergencies and 60 unscheduled landings. Our expert sources said this was a remarkably high number of incidents for an airline this size.