United CEO Scott Kirby is seeking to reassure customers following several recent incidents.
"Safety is our highest priority and is at the center of everything we do," Kirby wrote in an email to customers Monday. "Unfortunately, in the past few weeks, our airline has experienced a number of incidents that are reminders of the importance of safety. While they are all unrelated, I want you to know these incidents have our attention and have sharpened our focus."
The FAA is investigating several United incidents from this month, though none of have caused injuries or fatalities.
The most recent took place Monday, when a United Boeing 767 heading to London Heathrow returned to Newark due to a potential landing gear issue.
The FAA is also investigating what happened on March 15, when a United older generation Boeing 737 that had landed safely in Medford, Ore., was found to be missing an exterior belly panel.
On March 7, a tire fell off a United Airlines Boeing 777 while departing from San Francisco for Osaka, Japan. The tire landed in an employee parking lot at SFO, damaging several cars. No injuries were reported. The flight was diverted to Los Angeles, where the plane landed safely.
In another incident, this one on March 11, a United Boeing 777 traveling to San Francisco from Sydney returned to Australia after experiencing what the airline described as a "maintenance issue" en route.
Meanwhile, on March 14 a United Airbus A320 safely completed its route between Dallas and San Francisco after the crew reported a possible hydraulic issue.
The FAA is investigating five other incidents that happened this month. They've come at a time when flying safety is receiving heightened public scrutiny in the aftermath of the Jan. 5 exit plug blowout on an Alaska Airlines-operated Boeing 737 Max 9 flight, as well as due to ongoing revelations about failures in Boeing's quality-control processes.
In his letter, Kirby said that United is reviewing the details of each of the recent incidents, and that insights gained will inform safety training and procedures.
He noted that the airline had already planned to institute an extra day of pilot training beginning in May, as well as a centralized training curriculum for all new-hire aircraft maintenance technicians.