By Stacey Leasca
October 10, 2019

U.S. regulators hit Boeing with more bad news this week after they found cracks in several planes built by the aviation giant.

The cracks, USA Today reported, were discovered by inspectors while the airplanes were being converted from passenger to cargo planes. A total of 13 Boeing 737 NG airplanes have now been grounded worldwide. Two of the planes were grounded by Southwest, while 11 more were grounded by Brazil’s Gol Linhas Aereas.

"Boeing regrets the impact this issue is having on GOL, as well as our 737 NG customers worldwide," Boeing said in a statement. "We are actively working with our customers with inspection findings to procure parts, develop repair and replace plans, and provide all the technical support needed to safely return every impacted airplane to service as soon as possible."

Gol Airline Boeing 737-800 at Foz do Iguacu Airport, Brazil
Credit: Getty Images

Inspectors told airlines to inspect a total of 165 of the 737 NG planes for structural damage after they found cracks on an airplane part known as the “pickle fork.” That part, USA Today explained, attaches the fuselage to the wing. Nearly all of the 165 jets in question were Southwest aircraft.

For its part Southwest explained it found no issue with the “vast majority” of planes, though it “removed the two aircraft from our operation and reported the findings to Boeing and the FAA.”

Reuters further explained, the 737 NG aircraft was first delivered to airlines in 1997. The NG was the third iteration of the 737 and precedes the 737 Max. All 737 Max aircraft remain grounded following two fatal crashes. And it appears the 737 Max will stay on the ground for a bit longer than expected.

American Airlines announced it won’t return the aircraft to service until mid-January, however, the FAA replied to that announcement saying it had no set timeline to return the airplane model to service. In the meantime, Southwest pilots are suing Boeing claiming the airplane manufacturer knew its planes weren’t safe before they even hit the market. Boeing called that claim “meritless.”