The Saturday plane crash in Chamberlain, S.D., that killed nine members of a prominent Idaho Falls family is tied with three other crashes for the second-deadliest private plane accident in the United States since 2002, according to the National Transportation Safety Board’s database.

The deadliest crash in that time period happened March 22, 2009 in Butte, Mont., on a cold, late-winter day and involved the same model of plane, the Pilatus PC-12. Fourteen people died in that crash.

The South Dakota crash happened Saturday a mile north of the Chamberlain Municipal Airport. The family was returning from a pheasant hunting trip. Only three of the 12 passengers survived the crash.

The National Transportation Safety Board is investigating the crash and a preliminary report detailing the likely factors is expected within two weeks. Investigators finished the crash scene investigation Wednesday, according to the NTSB’s Washington, D.C., office.

Pilatus Aircraft, the plane’s manufacturer, also sent a team to assist in the investigation and provide the NTSB with information on the plane. Thomas Aniello, vice president of marketing for Pilatus, said he could not comment on the investigation itself.

The Post Register spoke with attorneys and aviation experts to get an idea of what factors the investigators would consider. Both attorneys said their insight was based on their experience investigating similar crashes and that the conclusions may change based on the NTSB’s findings.

Daniel Rose of Kreindler & Kreindler, a law firm based in New York City that represented the families of the victims in the 2009 Butte crash, said the NTSB likely would be looking at the plane’s engine. Rose is a Navy veteran pilot and flew in Operation Desert Shield.

As evidence, Rose pointed to a photo of the plane’s propellers released Monday by the NTSB. At least one of the propeller blades in the photo shows no significant bending. Rose said he’d expect all the blades to be bent if the engine was running when it crashed.

Another of the blades closest to the ground is partially bent, though Rose said he would have expected more bending if the engine had been running at full power. The other two blades are obstructed or not visible in the photo.

Rose said he expects NTSB investigators will look into whether the engine and the fuel pump were functioning correctly.

Even though Chamberlain was under a winter storm warning at the time of the crash, Rose doubted icing on the wings was a factor in the crash, given how quickly the plane crashed after takeoff, assuming the pilot checked the wings before flying to make sure ice had not built up.

Federal Aviation Administration spokeswoman Elizabeth Isham Cory said small planes are not usually restricted from taking off during storms and that pilots are “the ultimate authority” for deciding whether to fly.

Kirk Hansen is presumed to have been the pilot, given that he had a private pilot certificate, according to the Associated Press.

Gary Robb of Robb & Robb LLC specializes in civil cases involving plane and helicopter crashes and has served as both co-chairman of the Aviation Litigation Committee of the American Bar Association Section of Litigation and past chairman of the Aviation Section of the American Association for Justice.

Robb said he suspects the pilot made the wrong decision in taking off in those weather conditions.

According to Robb, the Pilatus PC-12 is a “slow, workhorse type of plane.” He said icing may have been a factor, saying the plane was susceptible to ice buildup on the wings. He said the plane has rubber boots on its wings that inflate to break ice build-up, but that it may not be adequate for heavy ice buildup.

Robb also said weight would be a factor in the investigation. According to a brochure about the plane, its maximum payload is 2,235 pounds. When the plane is fully fueled, the max payload is 988 pounds. Robb said 12 people with luggage could have been too much weight for the plane if it was fully fueled before taking off.

According to the NTSB news release, the pilot purchased 150 gallons of Jet A fuel before takeoff, which would have meant the plane held close to its capacity for fuel.

The Pilatus website said the plane’s passenger capacity is for 10 passengers and a pilot. The plane in the 2009 crash in Butte also was carrying more passengers than recommended by the manufacturer.

Both attorneys said the NTSB would be looking at the weather information available to the pilot before takeoff. Most airports subscribe to a weather service to track conditions for takeoff and landing.

The full investigation is expected to take up to two years, according to the NTSB news release. Aniello, Robb and Rose all offered condolences to the family while the investigation is underway.