Southwest Airlines canceled more than 40 flights nationwide Sunday so the company can inspect engine fan blades.

The move comes after the mid-air incident last Tuesday, April 17, where an engine exploded on Flight 1380. The explosion damaged sections of the wing and fuselage where a passenger, 43-year-old Jennifer Riordan, was partially blown out of a window and later died.

READ MORE | FAA will order engine inspections after deadly Southwest Airlines flight

Federal investigators are looking to see whether a broken fan blade on the engine was to blame for that event.

Southwest said in a news release that this move to cancel flights on Sunday comes as a part of their accelerated engine fan blade inspection program, announced on Tuesday night — not the emergency directive issued by the Federal Aviation Administration on Friday. The directive requires operators to inspect fan blades on certain engines within 20 days, according to the FAA's website.

The total number of flights canceled by the airline as of Sunday afternoon was 48, according to the tracking website FlightAware.

The Dallas-based airline said they minimized impact to flights last week by re-routing aircraft and using spare aircraft when available. Additionally, they said they've conducted inspections overnight.

As of Sunday afternoon, Southwest canceled more than a dozen flights to and from Dallas Love Field, according to FlightAware.

Read more from NBC Dallas-Fort Worth's website.