Night flights out of Hill Air Force Base will increase about 20 percent as new night navigation and weapons systems are installed on the F-16s stationed there, according to a Hill spokesman.

Maj. Roger Benninger of the 388th Tactical Fighter Wing at Hill told the Layton City Council on Thursday that total takeoffs and landings will not increase but more sorties will be shifted to night training.The Air Force is installing a LANTIRN system on the F-16s, electronic pods that allow pilots to see the ground and acquire targets through infrared and laser imaging.

Benninger said the pods were used extensively in the Persian Gulf war and proved their worth. They not only allow pilots to fly at night but also through smoke, haze and dust storms, Benninger said.

The F-16C models flown by the 388th TFW were scheduled for LANTIRN installation previously but the modification was delayed when the wing was sent to the Middle East last fall, Benninger said.

Benninger said 16,000 sorties a year are flown out of Hill, mostly training missions to the Utah Test and Training Range west of the Great Salt Lake.

That number will not change, he told the council, but the 1,700 missions previously flown at night will increase to 2,000, up 19 percent.

"The number of sorties flown is a pie. The size of the pie won't change but the slices will. We're dividing the pie in a different way," Benninger said.

The Air Force is planning 4,000 LANTIRN-related flights a year out of Hill, he said, with half at night.

Night flights are classified as takeoffs between sundown and 10 p.m. There are no takeoffs after 10 p.m. under normal cirumstances, Benninger said. The training flights to the Utah Test and Training Range could return to the base between 11 p.m. and 11:30 p.m., but that noise level is much lower than a takeoff with an afterburner, he said.

Daylight Saving Time is also a factor in flight scheduling, Benninger said. Fewer night flights will occur between April and September because of the smaller "window" of darkness between sunset and the 10 p.m. cutoff time for takeoffs.

Night training flights will increase from about 50 per month in the summer to around 200 per month in March and October because of the larger window of takeoff time, he told the council.

The new F-16C models at Hill have more powerful engines, Benninger said, which is both good and bad for noise levels. They are noisier on takeoff but accelerate faster so the pilot can throttle back sooner, he said.