HILL AIR FORCE BASE — F-35s at Hill Air Force Base will be keeping some unusual hours this week while participating in an unspecified military exercise.

Micah Garbarino, spokesperson with Hill’s 388th Fighter Wing, said communities surrounding the base will hear increased jet activity during the early morning hours this week, as a number of aircraft will depart after midnight and return during pre-dawn hours.

The atypical flight times are necessary, Garbarino said, for the aircraft to make round-trip flights in support of an off-station military exercise. Garbarino said he is not authorized to release specifics about the exercise, like where exactly the jets will be heading, their local flight patterns or how many aircraft will be involved. He said the exercise is a “joint” effort that will be done in tandem with other military outfits.

“We just don’t want people to be alarmed by how late we’re taking off,” Garbarino said.

The exercise is scheduled to wrap up by Friday morning.

Garbarino said Hill pilots regularly fly a limited number of night hours to meet Air Force proficiency requirements. Pilots are required to train at night to maintain their combat readiness and all-weather capabilities, but this week’s exercise is not part of the fighter wings’ regularly scheduled night time flying requirement. During night flying operations, pilots typically conclude training by 11 p.m. and often times even earlier than that.

As the Air Force’s only fully equipped, combat capable F-35 unit, the 388th and 419th fighter wings must be prepared to launch any number of aircraft to support the national defense mission at a moment’s notice, according to a base press release.

Hill fighter squadrons have served three Middle East combat deployments in less than two years and have been continuously deployed in combat with the F-35 for more than 18 months. Each of the wing’s three squadrons, alongside reservists from the 419th Fighter Wing, have deployed in support of the Air Force Central Command’s mission at Al Dhafra Air Base, United Arab Emirates.

The 4th Fighter Squadron, which deployed in April 2019, was the first. The 34th FS deployed in October 2019 and returned home in June and July, and the 421st FS is currently deployed — made up of pilots and maintainers and some personnel in other support functions. The group is performing close air support missions and supplying air and maritime escorts for other U.S. military groups.

The 4th FS’s mission, which ended in November 2019, marked the first time the Air Force’s F-35 jets performed a real-world combat operation, and the group completed at least two combat strikes on enemy forces, according to a press release from the Department of Defense.