SHELDON—The National Transportation Safety Board and the Federal Aviation Administration continue to investigate a plane crash that killed three Wisconsin men en route to a South Dakota hunting expedition on Tuesday, June 23, near Sheldon.
While a preliminary accident report was expected to be released this week, nothing was available as of press time on Thursday.
However, NTSB senior air safety investigator Aaron Sauer, who is in charge of the investigation, offered a closer look at what might have brought down the 1968 Piper PA-28 single-engine airplane, as well as the next steps the NTSB plans to take to further the investigation.
According to information released by the FAA, Frank Allegretti, 63, of Cambridge, Tom Boos, 60, of Fort Atkinson and Malcom McMillan, 65, of Milton, were flying the refurbished red and white four-seater, co-owned by McMillan, to a prairie dog hunting excursion in Winner, SD, when the aircraft crashed about 11 a.m. into an embankment along gravel road 310th Street between Oriole and Pierce avenues about four miles east of Sheldon and a mile north of Highway 18.
Sauer said investigators are not sure who was flying the plane.
He said Allegretti was seated in the left front seat, McMillan was seated in the right front seat, and Boos was seated in the back seat and could be considered a passenger.
While the left front seat is commonly where the pilot is seated, Sauer said both Allegretti and McMillan each had private pilot’s licenses and were seated with controls in front of them, so either could have been piloting the aircraft.
“It will take some additional work to see if we can determine who was flying and who wasn’t,” he said. “If we cannot determine that, we most often go with whoever was seated in the left front seat.”
Sauer said the aircraft departed from Fort Atkinson Municipal Airport on Tuesday at an unknown time.
He said no flight plan was filed, although a hand-held global positioning system was found on board the plane and may help investigators determine the flight’s history, including what led the aircraft to crash, coming to rest in an inverted position.
Sauer said witnesses saw the aircraft shortly before the crash, but he has not located anyone that actually saw the plane go down.
“Two witnesses did observe the plane flying low,” Sauer said. “They heard the engine sputter and cough. The engine then quit, restarted and quit again.”
Sauer said the plane then was lost behind some trees north of the accident site.
“Others observed the plane flying low, and one witness observed the wings rocking back and forth,” Sauer said.
Investigators found skid marks on the cornfield north of 310th Street heading in a southward direction. Measurements taken at the accident site indicate a distance of 100 feet between initial contact with the cornfield and 180-horsepower Lycoming engine’s resting point.
Mike Buss, a meteorologist at the National Weather Service station in Sioux Falls, SD, said thunderstorms rolled in the area during late morning, with 0.23 inch of rain falling and up to 45 mph wind gusts. Despite the conditions, authorities have been hesitant to speculate a cause.
“It’s way too early to speculate on a cause,” Sauer said. “We’re still in the fact-gathering stages. We have several pieces to place together before we take the time to even start thinking about a cause.”
Three such pieces Sauer said the NTSB is looking into are man, machine and environment.
The NTSB still is waiting to receive information on McMillan’s and Allegretti’s pilot training and expertise, which most often is gathered from family members. Board members also are continuing to inspect the aircraft and Sauer is working to obtain information about the weather and terrain of the accident site.
“We’re still trying to gather all of this information,” Sauer said. “It takes a while to get everything tracked down.”
The plane, which was removed from the site on Wednesday, June 24, by a recovery operation from Minneapolis, will remain in a secure location until the investigation is completed.
Sauer said autopsies were performed on all three victims at the State Medical Examiner’s Office in Ankeny, but he has not received the results. Toxicology tests also are being conducted on McMillan’s and Allegretti’s bodies by the FAA.
After the preliminary crash report is released, a detailed factual report on the crash will not be completed for six to nine months. The NTSB office, based in Washington, D.C., then will review the report and assign a probable cause, which will be made public.
“One thing that important to remember is that if there were any safety issues identified, we would address those immediately,” Sauer said. “We did not find any issues, and that is important for the public to keep in mind, that this accident has nothing specifically related to any other similar aircraft out there.”
This article appeared in the July 4, 2009 edition of The N'West Iowa REVIEW.