Agencies, Jakarta – Indonesia has allowed three Boeing 737 MAX 9 planes to fly again after grounding them, as they have different configurations from a jet that was forced to make an emergency landing in the United States on Jan. 5, the Transportation Ministry said on Thursday.
A cabin panel broke off a new Boeing 737 MAX 9 jet operated by Alaska Airlines in mid-flight, leading to the grounding of the model and inspections by the US Federal Aviation Administration (FAA).
The incident occurred after take-off from Portland, Oregon, en route to Ontario, California, forcing pilots to turn back and land safely with all 171 passengers and six crew on board.
After grounding the three planes operated by Lion Air on Jan. 6 and later inspecting them, Indonesia's transport ministry said it had allowed them to fly again since Jan. 11.
Lion Air said in a statement the planes had different configurations from the Alaska Airline plane.
The transport ministry said the Lion Air planes had a "mid cabin emergency exit door type II" whereas the Alaska Airlines plane had a "mid exit door plug."
Boeing shares tumbled last week as investors began to assess the financial implications of the incident, while US aviation authorities provided airlines with protocols to check planes with similar configurations to the 737 MAX 9 aircraft involved in Friday's incident.
National Transportation Safety Board (NTSB) inspectors have said that they did not find bolts for the component that came off on Friday's Alaska Airlines flight, but hadn't determined whether they existed or had flown off with the panel.
Through further equipment testing, "we will be able to determine whether the bolts were there," NTSB Chair Jennifer Homendy told reporters.
Homendy didn't comment directly on the latest disclosures from United and Alaska about loose components, saying the probe was focused on Friday's incident. But the board could issue an urgent safety recommendation if need be, she said.
Hundreds of flights have been canceled due to the grounding of a fraction of the MAX fleet.
Aviation analysts said the issue appeared to be a quality control defect rather than a design issue akin to the problem with a flawed flight handling system involved in two fatal MAX crashes in 2018 and 2019.
But Boeing has struggled with supply chain and quality control problems since the MAX returned to service, limiting its output and hitting its bottom line.