Delays across the Southwest Airlines departures schedule have been reported, as the carrier completed emergency checks on its Boeing 737-300 fleet.
The move follows the mid-air rupture of the fuselage skin on Southwest Airline flight 812 on Friday.
No injuries were reported following the incident, with the aircraft making an emergency landing in Yuma, Arizona.
Checks on 21 Boeing 737-300 planes have so far been carried out, according to Southwest Airlines, with two founded to be in need of repair.
The remaining 19 others were returned to service, Southwest said.
Southwest cancelled approximately 300 flights yesterday while the inspections are ongoing.
“Our highest priority is the safety of our Employees and Customers,” said Mike Van de Ven, Southwest’s chief operating officer.
“Prior to the event regarding Flight 812, we were in compliance with the FAA-mandated and Boeing-recommended structural inspection requirements for that aircraft.
“What we saw with Flight 812 was a new and unknown issue.”
The National Transportation Safety Board has also been made aware of the incident.
“The NTSB, along with the other investigative parties - Federal Aviation Administration, Boeing, and Southwest Airlines - has been working to determine what actions might be necessary to inspect any similar airplanes.
“As a result of the findings from our investigation to date and the results of the Southwest Airlines inspections, Boeing has indicated that they will be drafting a Service Bulletin to describe the inspection techniques that they would recommend be accomplished on similar airplanes.”
Metal fatigue was earlier blamed for an 18-by-12 inch rip in a Southwest 737 in July 2010.
That aircraft was flying at 35,000 feet, in an incident that also forced an emergency landing.
In January 2010, the Federal Aviation Administration ordered fuselage checks for metal fatigue on 135 737-300s, -400s and -500s in the US, after Boeing recommended such checks in September 2009.