Inside the Southwest engine that failed

Manufactured in Evendale, Ohio, and Durham by joint venture between GE Aviation and France-based Safran Aircraft Engines, the CFM56 is the best-selling jet engine by far. Over 30,000 have been delivered to more than 550 operators worldwide. The line dates back to 1974, and, while most CFM56 engines are assembled at GE Aviation's Evendale, Ohio, facility, some have been assembled in Durham since 1999.

The engine line powers Boeing 737 aircraft including the 700 and 800 models which make up nearly all of Southwest’s fleet. The military uses the same engine, under the F108 designation, to power some KC-135 Stratotankers, C-40 transports as well as the Navy’s P-8 Poseidon submarine-hunting aircraft.

You might expect to find fan blades on a propeller-driven aircraft rather than in a modern jet engine. However, hot gases exiting through the exhaust produce only 20 percent of the engine's thrust, the rest comes from air flowing around the combustion chamber at speeds increased by the fan at the front.

Twenty percent of the air entering the engine flows through the combustor. Compressors increase air pressure incrementally across 12 stages before entering the combustion chamber where fuel is mixed with air and burned. The expanding gases drive turbines in the next stage, which turn a shaft running through the center of the engine driving the compressors and fan. Air mixes again and exits through the exhaust.

GE Aviation employs more than 1,400 people across North Carolina at facilities in Asheville, Wilmington, West Jefferson and Durham.

The facility on Miami Boulevard in Durham has been manufacturing aircraft engines since 1993, contributing to nine engine lines for GE and joint partners like CFMI.