Australian airline Qantas Airways Ltd has found structural cracks in three of its Boeing Co 737 NG planes after conducting earlier-than-required checks of its aircraft, as part of a global issue with the model.
“Of the 33 of Qantas’ 737 aircraft that required inspection, three were found to have a hairline crack in the pickle fork structure. These aircraft have been removed from service for repair,” Qantas said in a statement on Friday.
The “pickle fork” is the part that attaches the plane’s fuselage, or body, to the wing structure.
All three Qantas jets had approximately 27,000 take-off and landing cycles rather than the 30,000 that had required immediate checks, but the planes were inspected in line with advice from regulators, the airline said in a statement.
“Qantas will minimise any customer impact from having these aircraft temporarily out of service,” the carrier said. “All three aircraft are expected to return to service before the end of the year.”
The issue surrounding the 737 NG is the latest safety concern for Boeing, as it tries to deal with the fallout from crashes of two 737 MAX planes – which are newer than the NG model – that killed 346 people and highlighted problems with the MAX’s flight handling software.
The United States Federal Aviation Administration (FAA) issued a directive in October giving airlines a matter of months to check 737 NG aircraft with more than 22,600 cycles but fewer than 30,000.
Qantas on Wednesday said it had discovered cracks in a jet with just under 27,000 cycles undergoing heavy maintenance. It then stepped up checks on 33 of its planes with more than 22,600 cycles, finding cracks in another two.
Repairing the cracks requires grounding the planes, with remedial work costing an estimated $275,000 per aircraft, according to aviation consultancy IBA.
Other carriers that have discovered pickle fork cracks include US-based Southwest Airlines Co, Brazil’s Gol Linhas Aereas Inteligentes SA, Korean Air Lines Co and Indonesia’s Sriwijaya Air.
Boeing said on Thursday that of the slightly more than 1,000 planes that had required checks to date, cracks were found in fewer than five percent of them.
The FAA initially said Boeing notified the agency of the problem after encountering the issue on a plane in China and that subsequent inspections showed other planes also had cracks.