The number of private pilots in the U.S. has been steadily falling and is a big factor in the closure of hundreds of airports.

Since peaking at 357,000 in 1980, the number of pilots with private certificates has plunged to 188,000.

That drop is a big reason hundreds of small, rural airports have closed.

In Onawa, Iowa, planes will stop flying into the airfield for the first time in 60 years. Instead, the runway will be used as a racing dragstrip.

Officials in Hillsboro, Illinois, sold off their airport to a company that is mining for coal.

Gene Martin, who owns a private airfield in South Sioux City, Nebraska, says business has slowed, but he's holding on despite offers for his land.

Martin says, "That's all I've ever done."