About 5% of all Boeing 737 Next-Generation aircraft inspected under an October Federal Aviation Administration order have exhibited a crack in a particular component. The discovery has caused both Southwest Airlines and Quantas Airways each to idle three aircraft discovered to have the cracked "pickle fork" that attached a plane’s fuselage to the wing structure.
The 737 Next-Generation is the third version model of the 737 series, the one that preceded the current 737 MAX model. The issue that prompted the FAA’s inspection order is separate from the flight-control issue that has idled the entire 737 MAX fleet since March.
The 737 NG inspections were conducted after Boeing warned about the issue and FAA ordered inspections within a week for aircraft that had flown more than 30,000 flights and for aircraft between 26,000 and 29,999 cycles within 1,000 flights.
The 737 NG was introduced in 1996, and remains in production still though the 737 MAX has replaced it as the primary model since the latter was introduced in 2017. Records show 7,031 737NG aircraft have been delivered since its commercial debut, with several dozen more still on order.
According to Boeing, various airlines around the world have inspected 2,000 737 NGs and found structural cracks in the particular part in less than 5% of those jets.
The inspections were conducted after Boeing warned about the issue and the Federal Aviation Administration ordered inspections within a week for aircraft that had flown more than 30,000 flights and for aircraft between 26,000 and 29,999 cycles within 1,000 flights.
Boeing said more than 1,000 planes met the conditions for the inspections and less than 5% qualified for repairs.
In addition to Southwest Airlines and Quantas, Brazilian carrier Gol grounded 11 737 NG jets.
American Airlines, Delta Air Lines, and United Airlines also operate the 737 NG aircraft, and none have report any defects to the jets in their fleets.