What happened with United Airlines aircraft at Medford Airport in Oregon?

In yet another Boeing mishap, a United Airlines aircraft on Friday touched down at Medford Airport, in Portland, Oregon without an external panel, Fox News reported.

In a statement, United Airlines announced that its Flight 433 which took off from San Fransisco, landed at Medford Airport around 1:45pm PDT on Friday 139 passengers and six crew members onboard.

However, the statement also revealed that the flight's Boeing 737-800 aircraft was "discovered to be missing an external panel" while it was parked at the gate.

The statement added: "We’ll conduct a thorough examination of the plane and perform all the needed repairs before it returns to service. We’ll also conduct an investigation to better understand how this damage occurred."

While some sources have reported that the plane lost the panel during flight, United Airlines said that the plane did not declare an emergency while en route to Medford "as there was no indication of the damage during the flight".

Following the mysterious incident, the Federal Aviation Administration (FAA) has initiated a probe into the incident to find out how the 25-year-old aircraft lost an external panel before landing in Oregon.

Boeing did not comment, directing questions to United Airlines. According to FAA records, the plane was built in late 1998.

Traffic was briefly halted at the airport to search for the panel.

The US aviation industry is getting increased attention following the Alaska Airlines Boeing 737 MAX 9 mid-air emergency which was caused by a door plug blowout.

Additionally, Boeing has come under heavy regulatory scrutiny for safety and quality standards after several incidents have been reported involving its aircrafts.

United has announced that the aircraft involved in Friday’s incident will remain grounded until repairs and the investigation are completed before returning it to service.