The troubled 737 Max resumed flying last month, with American Airlines Flight 718 making the first commercial flight of the plane after the F.A.A. lifted its grounding order in November. Before they are permitted to fly again, each 737 Max aircraft must have its wiring and software modified.
The 737-500 was introduced with the purchase of 20 planes in 1987 by Southwest Airlines. The airline used the model, with a capacity of 122, to more efficiently handle longer routes with a smaller number of passengers, Southwests corporate historian, Richard West, wrote in 2016. That need dropped as its long-haul travel business increased, and Southwests last 737-500 flew in September 2016.
Historically, the 737-500 has been a safe plane to fly. The series it belongs to, which includes the 737-300 and 737-400, has had 19 fatal accidents over more than three decades in operation, or about one fatal accident for every four million departures, according to a 2019 Boeing report.
Four previous fatal accidents have been recorded in the 737-500, including crashes in South Korea in 1993, Tunisia in 2002 and in Russia in 2008 and 2013, according to the Aviation Safety Network.
Boeing manufactured 389 of the 737-500 before the model was discontinued. As many as 100 remain in use by smaller airlines around the world in countries including Afghanistan, Iran, Nigeria, Russia and Ukraine, according to the tracking website Planespotters.net.
