In the aftermath of an incident involving an Alaska Airlines plane, United Airlines revealed on Monday that it had discovered loose bolts during inspections of its 737 Max 9 fleet. The issue was brought to light after a door plug was blown out of an Alaska Airlines aircraft over the weekend.

Although United did not disclose the exact number of planes affected, the airline confirmed that preliminary inspections conducted on Saturday had identified instances of installation issues in the door plug. Specifically, bolts were found to require additional tightening. United swiftly assured that its Tech Ops team would address these concerns to ensure the safe return of the aircraft to service.

Following the Alaska Airlines incident, the Federal Aviation Administration (FAA) grounded all 737 Max 9s as a precautionary measure. In an official statement, the FAA prioritized public safety, explaining that the affected planes would remain grounded until they were deemed safe by the regulatory authority.

It is estimated that United's emergency inspections resulted in the cancellation of 200 Max 9 flights on Monday, with further significant cancellations expected on Tuesday. The airline has been proactively taking necessary steps to address the loose bolt issue and minimize any potential risks to passengers.

The National Transportation Safety Board (NTSB), responsible for investigating the Alaska Airlines incident near Portland, Oregon, has yet to comment on United Airlines' findings. NTSB investigators have recovered the door plug that detached from Alaska Airlines Flight 1282 on Sunday. This crucial piece of evidence, weighing 63 pounds and measuring 26-by-46 inches, will undergo thorough examination to determine the cause of the incident.

The incident occurred around 5:11 p.m. local time on Friday, when the Alaska Airlines Boeing 737 Max 9, carrying 171 passengers, was climbing to 16,000 feet after taking off from Portland International Airport. The sudden loss of the door plug caused an "explosive decompression" and compelled the flight crew to swiftly return to Portland. Fortunately, no injuries were reported among the passengers and crew members.

As investigations continue, the aviation industry remains focused on ensuring the highest level of safety for passengers. United Airlines, along with other carriers operating the 737 Max 9, will closely adhere to the guidance provided by regulatory authorities to resolve any maintenance issues and prevent similar incidents from occurring in the future.