The effort included nearly 100 searchers on foot and tractor-treaded vehicles and snowmobiles recruited from Valley County, neighboring counties and the state. Also, a fleet of five planes from the Civil Air Patrol and Idaho Department of Transportation and four helicopters were in the air Thursday afternoon.
Two of the helicopters, Apaches provided by the Idaho Army National Guard, have infrared imaging abilities. Limited visibility forced some of the aircraft to turn back several times Thursday.
"We are extremely thankful for the support we have been getting from multiple organizations," said Valley County Sheriff's Lt. Dan Smith. "This search has been a cooperative effort from the beginning and continues to be so."
Searchers suspended their fruitless efforts Thursday before 7 p.m. but promised to continue searching Friday, albeit with storms limiting resource deployment.
"We are all frustrated that we have not yet been able to locate the missing plane but we will continue to search," Smith said.
A faint emergency locator transmitter signal had been noted on Tuesday, and Wednesday's search targeted an area south of the Johnson Creek airstrip, near Yellow Pine, Idaho. However, other aircraft searching the same area could not pick up the signal.
As a result, Thursday's search was expanded to include more of the area about 100 miles northeast of Boise, near the Frank Church-River of No Return Wilderness Area.
Ground teams focused on drainages east of Johnson Creek airport while aircraft were assigned to grid pattern searches of specific areas in the vicinity.
Aboard the missing six-seat, early 1980s model BE-36 Beech Bonanza were the pilot, Dale Smith; along with son Daniel Smith and his wife, Sheree Smith; and daughter Amber Smith with her fiancé, Jonathon Norton, who grew up in Salt Lake City.