On May 10, UPS2949, an MD-11 enroute from KOAK to KONT, had just departed runway 30 at KOAK when the flight crew called Norcal Departure and advised them that were stopping their climb at 4000 feet due to flight control issues. They declared Mayday a few minutes later and asked to return to KOAK's runway 30. They landed safely about 15 minutes later and taxied back to the apron on their own.
https://www.flightaware.com/live/flight/UPS2949/history/20240510/1335Z/KOAK/KOAK
