A construction management company executive, his wife and their 17-year-old son along with the 67-year-old pilot died when their small plane crashed on a college scouting trip to the University of Oregon, officials said Saturday.

The family from Thousand Oaks, California, was headed to Eugene with their son, who is a high school senior, because he was considering attending the university, a family friend told The Oregonian/OregonLive.

The Linn County Sheriff's Office identified them as John A. Zitting, 42, Karen Blackmore Zitting, 37, and John Brendan Zitting, 17.

Mark Gregory Aletky of Acton, California, was the pilot of the 1984 Piper PA-46-310P that crashed Friday morning in a field near Harrisburg.

The single-engine, six-seat plane known popularly as a Piper Malibu, is based out of Van Nuys, California, and is registered to Park City Aviation LLC in Park City, Utah.

The plane left Van Nuys at 7:22 a.m. Friday, the sheriff's office said.

Investigators learned the plane was flying on instrument and was approaching the Eugene Airport, the sheriff's office said in a news release.

Witnesses in Harrisburg described seeing the plane flying north at a low altitude when, for unknown reasons, it suddenly turned and crashed into a grass field just west of Peoria Road, about two miles north of Harrisburg.

"It is unknown at this time why the plane continued north past the Eugene Airport," the news release says, adding that the Linn County Sheriff's Office 9-1-1 Center received a call about the crash at 10:53 a.m.

The wreckage is scheduled to be removed this weekend.

Autopsies on Aletky and John Zitting are being conducted Saturday. John Zitting was found in the front passenger seat of the plane. Karen Zitting was seated behind the pilot. Their son was seated behind his father.

Zitting is president of TruNorthe LLC, a construction management company.

TruNorthe's director of human resources, Tara Harris, described John Zitting as fun, entertaining and a hands-on leader.

"He was very well liked, well loved," Harris said. "I've had a lot of bosses, and I really didn't care when their birthday was. Everybody cared about his birthday. We had a party."

Zitting had recently been traveling a lot in an effort to grow TruNorthe, Harris said. The company now employs about 30 people. Six or seven were hired in the past couple of weeks, Harris said.

Zitting was excited to have bought a plane and hired a pilot, said Harris, who met Mark Aletky when he dropped off paperwork at the office. Aletky was a full-time employee of TruNorthe, Harris said.

"They were great people," said Sean Sullivan, marketing director for TruNorthe.

"His son was going off to college and that's why they were going to Oregon," Sullivan said, adding that the younger Zitting, a senior at West Lake (California) High School was also considering the University of Arizona and other schools. The son was the couple's only child.

Zitting started TruNorthe in 2010, Sullivan said. While it is based in Park City, Utah, Zitting primarily worked out of the company's Burbank, California, office.

"John by trade was a builder. He built homes, hotels, chalets," in Utah and Wyoming, Sullivan said.

Aletky was a professional drummer in California before deciding at age 45 that he wanted to be a pilot, embarking on a second career in which he rose in qualifications to the point where he flew Lear jets, said his son Joseph Aletky.

Joseph Aletky said his father had attended a training course in northern California specific to the Piper PA-46-310P. He also said his father had experience in flying aircraft in a wide variety of situations and, in a profession that measures experience in time in the aircraft, "had thousands and thousands of hours."

Aletky, 30, said his father, who also has worked as a flight instructor, started teaching him how to fly when he was a boy. He said he knew he was biased in his opinion of his father's flying abilities.

But, "Out of all the pilots I've met, he was extraordinary in his ability. I know if any situation would arise, he would be the guy to meet that."

Aletky, one of the pilot's three children, said he was perplexed by what he has read thus far about the crash.

"I can't understand it. We've had things happen in the air. We've dealt with it. He's not the type to panic. He takes things by the reins and makes sure what needs to get done gets done."

A National Transportation Safety Board investigator, meanwhile, plans to interview three witnesses Saturday who saw an airplane plummet to the ground.

The investigator also will work to continue gathering data on the plane, pilot and circumstances surrounding the crash, said NTSB spokesman Peter Knudson.

Three witnesses interviewed by The Oregonian/OregonLive on Friday gave a similar version of events preceding the crash: A low-flying plane suddenly flipped on its side then traveled traveled straight down until it was out of sight. Strong winds buffeted the area at the time.

The investigator for the NTSB, which is the agency that will determine the cause of the crash, expects to be in the Harrisburg area until Sunday, Knudson said. More than one tablet computer was recovered from the site, he said, and they will be shipped to the NTSB headquarters in Washington, D.C., for inspection because one of them likely was used for navigation.

In addition to looking at weather conditions at the time of the crash, the investigator will want to know what weather information was available to the pilot prior to departure and how current the information was. In general, the investigator will want to know the pilot's pre-flight planning, he said.

"We'll try to understand what happened to pilot three days prior," he said, a routine part of a crash investigation, searching for "anything that could have affected the pilot's ability to safely operate that aircraft (such as) sleep, rest cycle."

Also, the pilot's license will be considered, along with hours of experience, recent flying experience, medical certification and medical records.

The aircraft will be examined along with its maintenance records, Knudson said. "Was there sufficient fuel?" he said, posing another area the NTSB would consider. The fact there was no post-crash fire was "helpful," he said, as no instrumentation was destroyed.