HILO, Hawai'i — Crews checked a 400-square-mile section of the southern half of the Big Island yesterday using helicopters and fixed wing aircraft, but were again unable to find a trace of a missing Cessna tour plane that disappeared Tuesday.

The helicopter search in the morning focused on mauka areas from the 3,000- to 7,000-foot elevation to try to get a good view of isolated slopes of Mauna Loa in Ka'u and South Kona before the morning clouds closed in, but Big Island Assistant Fire Chief Clesson Murasaki said searchers were unable to check much above 3,500 feet after the area clouded over.

Some searchers shifted to coastal areas in the afternoon in an effort to spot any debris that might be scattered along the shore.

Murasaki said two fire department helicopters participated in the search with help from four airplanes from Island Hoppers. The U.S. Coast Guard ended its role in the search Thursday night.

A ground crew that included personnel from the fire department and Civil Air Patrol traveled on back roads and trails in areas mauka of Hawaiian Ocean View Estates and used hand-held monitors to try to detect a signal from the plane's emergency broadcasting equipment, Murasaki said.

Crews have searched since Tuesday for the Island Hoppers Cessna 172 piloted by Katsuhiro Takahashi, 40. The plane carried Japanese tourists Nobuhiro and Masako Suzuki, 53 and 56, from Chiba prefecture, and never returned from what was supposed to be a three-hour flight clockwise around the Big Island from Kona airport.

The plane was last seen by another Island Hoppers pilot near Kilauea volcano, and search aircraft focused yesterday on a 400-mile area that makes up the southernmost portion of the island, Murasaki said.

The Coast Guard estimated it had searched more than 10,000 square miles this week, but Murasaki said the county wanted to check more carefully on the southwestern rift zone of Mauna Loa.

"We're trying to cover the forest areas a little better, especially the upper elevations," Murasaki said. "All this time, the weather wasn't really cooperating that much with us, so we try to get in early before it starts coming in on us."

He said the fire department helicopters planned to start earlier today, about 5 a.m., to allow for more search time before the clouds close in for the day.

If there is wreckage on the slopes of the volcano, he said the largest pieces could be little larger than a table. "Sometimes, we're just looking for broken branches. That's a telltale sign, and the (forest) canopy will just close up."

The plane was last seen at about 12:45 p.m. Tuesday over Hawai'i Volcanoes National Park by another Island Hoppers pilot, and Murasaki said there is a "high probability" the plane flew southwest from there in keeping with pilot Takahashi's flight plan.

"It's just now whether he went over the mountain, or did he stay over the ocean. Still, that's a large area to search, especially with the forest," he said.

The county plans to continue the search though tomorrow, and will consider extending the search beyond then if the family requests it, Murasaki said.