GLENDALE, Ariz. (AP) -- Night flying exercises at Luke Air Force Base in Glendale will increase this month. Luke officials say F-16 student pilots from several squadrons will be flying Monday through Friday until 11:30 p.m. daily. The flights will not involve any F-35 fighter jets and will not take place on the weekends. The additional night flying will occur throughout the month of August. Base officials say nighttime training is an integral part of students' training. The base, located 15 miles west of Phoenix, is allowed to fly 24 hours a day. However, officials say they try to limit late-night flights to reduce the impact on surrounding communities.