A United Airlines Boeing 737-900ER aircraft was forced to return to Chicago O'Hare International Airport (ORD) after the narrowbody suffered cabin pressurization issues on July 3, 2024.

Incident overview

The United Airlines Boeing 737-900ER jet was performing scheduled flight UA 343 from its base at Chicago O'Hare International Airport (ORD) to San Francisco International Airport (SFO) when the aircraft was forced to divert back to its departure airport approximately an hour after take-off.

According to a report by The Aviation Herald, the carrier's Boeing 737-900ER jet was ascending to approximately FL250 after departing from Chicago when the crew halted the climb, descended the aircraft to 10,000 feet, and safely returned to Chicago, landing on runway 27C.

The replacement aircraft reached its intended final destination at SFO approximately three and a half hours later without further incident. It is worth noting that the journey between ORD and SFO takes approximately four hours on a Boeing 737-900ER, as per Flightradar24.com data.

The aircraft in question is one of United's many Boeing 737-900ERs, registered as N69830. The airliner is 10.1 years old and was delivered to United in June 2014, according to Planespotters.net data. The Chicago-based carrier currently has a total of 136 Boeing 737-900ER aircraft.

FAA will review incident details

In a statement, the United States Federal Aviation Administration (FAA) said that it will begin an investigation into this United Airlines incident. The US aviation regulator stated:

"United Airlines Flight 343 returned to and landed safely at Chicago O'Hare International Airport around noon local time on Wednesday, July 3, after the crew reported a pressurization issue. The Boeing 737-900 was en route to San Francisco International Airport. The FAA will investigate."

FAA's scrutiny over United's operations

In recent months, United Airlines has faced numerous safety incidents, leading the US aviation regulator to intensify its scrutiny of the airline's operations. As a result, the FAA suspended some of United's certification activities and subjected the carrier to increased scrutiny.

In May 2024, United Airlines claimed that it was cleared by the FAA to launch new routes and certify aircraft, which the carrier revealed in a memo to employees. In the memo, the airline shared the "good news" that the FAA Certificate Management Office had allowed it to "begin the process of restarting our certification activities," which includes new routes and aircraft.

However, a day later, the FAA denied granting approval for United Airlines to expand its network and fleet. Additionally, the FAA said it will require its personnel to be present during United's inspections of newly delivered aircraft.