NTSB issues report on fatal crash near Sanborn

Federal aviation officials say it may take about 60 days for the National Transportation Safety Board to finalize the cause of a small plane crash June 23 in a corn field near Sanborn.

The crash killed all three Wisconsin men on board and a factual report released Oct. 28 by the NTSB suggests the single-engine Piper was low on fuel. Ted Lopatkiewicz, an NTSB spokesman, said the board will use the factual report to issue a determination of probable cause.

"This is well along in the investigation," Lopatkiewicz said.

Francis Allegretti, of Cambridge, Wis., Thomas Boos, of Fort Atkinson, Wis., and Malcolm McMillan, of Milton, Wis., were flying from Fort Atkinson to Winner, S.D., on a hunting trip when the plane crashed just before 11 a.m. in rural O'Brien County.

The plane had two 25-gallon fuel tanks, according to the NTSB report compiled by agent Aaron Sauer. After the crash, investigators drained 1 cup of fuel from the tank under the left wing and 2 cups from the tank under the right wing.

Prior to departure, the airplane was refueled by the pilot and passengers at a self-serve fuel pump. A witness overheard portions of a conversation among the plane's occupants during fueling. One person in the group noted plans for a fuel stop along the route of flight.

A family member of one passenger also told investigators that, in the days preceding the accident flight, the passenger mentioned they could not depart with full fuel tanks due to the high temperatures and expected weight of the airplane.

In the moments before the crash "two witnesses, located northeast of the accident site, observed the airplane at a low altitude and the engine was 'coughing, sputtering and missing,'" the NTSB report said.

"The engine quit shortly thereafter, restarted and quit again."

The witnesses lost sight of the airplane behind trees. Approximately 5 minutes later, they heard sirens and emergency vehicles. Witnesses and rescue personnel who responded to the accident reported no smell or evidence of fuel at the accident site, according to NTSB.

Deputies found the plane partially on its top at the edge of a gravel road, O'Brien County Chief Deputy Allen Schuknecht said, shortly after the crash.

"It just flew into an embankment," he said. "It looked like it might have been able to land if it hadn't hit that road."

The National Weather Service in Sioux Falls, S.D., said thunderstorms with heavy rain were moving through the area at the time of the crash. Schuknecht said it was "real dark" and there were gusty winds, but weather conditions weren't cited as a prominent factor in last week's NTSB report.

"The weather at the time as reported by witnesses was clear skies and the winds were light and variable," the report said.