ALBUQUERQUE, N.M. -- The pilots of a helium balloon flying across the Pacific Ocean have matched a duration record as they approach North America, marking another historic day for the team that's already surpassed a distance record.

Pilots Troy Bradley of Albuquerque and Leonid Tiukhtyaev of Russia matched the milestone early Friday when they hit 137 hours, 5 minutes and 50 seconds in the air in a traditional gas balloon.

The duration record is considered the "holy grail" of ballooning achievements. It was set in 1978 when Ben Abruzzo, Maxie Anderson and Larry Newman made the first trans-Atlantic balloon flight.

To establish a record, international aviation rules require Bradley and Tiukhtyaev to stay aloft 1 percent longer than the current record.

On Thursday, the pilots eclipsed the distance record of 5,209 miles.