Weekends continue to be a particularly busy period for Honolulu Fire Department rescuers called on to assist lost and injured hikers on Oahu trails.

HFD’s Air 1 helicopter Saturday airlifted to safety a 24-year-old male and a 23-year-old female who ventured off the Kuliouou Valley Trail in Hawaii Kai, according to a news release. The call for help came in at 2:16 p.m., with HFD responding with four units staffed with 12 personnel. The first unit secured a landing zone at Kuliouou Valley Park so rescuers could board Air 1 and load equipment onto the aircraft for a search-and-rescue operation, the release said.

The two hikers were on the trail for about 90 minutes when they became lost. Using a signal from the pair’s cell phone, HFD rescuers were able to plot their geolocation “with a moderate-level of confidence,” the release said. Air 1 dropped rescuers near the plotted location and were at their side at 3:07 p.m. The hikers were flown to the landing zone at 3:21 p.m. and declined medical attention.

Air 1 also was called into serv­ice Friday night after two groups of hikers were reported lost on Manana Ridge Trail in Pearl City.

After receiving a 911 call at 7:20 p.m., HFD dispatched six units staffed with 20 personnel. The first unit arrived at the top of Komo Mai Drive at 7:37 p.m. and started climbing the trail on foot, while a second unit secured a landing zone near Pearl City High School, the release said.

The caller, a 26-year-old woman, reported she was hiking with three others when they became lost in darkness. HFD then received a call from a second set of lost hikers on the same trail. Rescuers made contact with that group at 8:03 p.m. and were able to lead them out of the trail safely.

Air 1 then dropped rescue personnel onto the trail and the first set of hikers was located at 8:15 p.m. All four members of that group were put aboard Air 1 and transported to the landing zone at 8:47 p.m.