The pilot, Bill Henningsgaard, was killed along with his son, Maxwell, and two children who were in a house struck by the small propeller-driven plane on Friday. Their bodies were all recovered from the crash scene.
East Haven police on Saturday released the names of the crash victims, including Henningsgaard, 54, of Medina, Wash.; his 17-year-old son; 13-year-old Sade Brantley and 1-year-old Madisyn Mitchell, who lived in the East Haven home hit by the plane.
National Transportation Safety Board investigator Patrick Murray said Saturday the plane was upside down when it struck a house at about a 60 degree angle. He said the pilot was making his first approach to the airport and did not declare an emergency before the crash.
After removing the wreckage and before analyzing any data, he said at a news conference in New Haven, "We don't have any indication there was anything wrong with the plane."
A preliminary NTSB report on the crash is expected within 10 business days. A more in-depth report could take up to nine months.
On Saturday night, dozens of people turned out for a vigil at Margaret Tucker Park to honor those who died in the crash. Among those in attendance was the woman who lost two children when the plane struck their house.
Mayor Joseph Maturo told the crowd at the vigil that the show of support was a great tribute.
"I think this is a great tribute to a great town," the mayor said, "a caring town, a loving town. A town that comes out when things are down and people need you."
Gov. Dannel Malloy said in a statement that the vigil was a "profound statement of the ties that bind East Haven and our entire state together as one community."
"When a family suffers an unimaginable tragedy, we come together and pray that they have the strength they need to carry on," Malloy said. "Our thoughts and prayers are with all the families tonight who are suffering from grief and loss."
Henningsgaard, a highly regarded philanthropist, was flying a small plane to Seattle in 2009 with his mother when the engine quit. He crash-landed on Washington's Columbia River.
"I forced myself to confront that fact that the situation any pilot fears - a mid-air emergency, was happening right then, with my mother in the plane," he wrote in a blog post days later.
In the Connecticut crash, Henningsgaard was bringing the 10-seater plane, a Rockwell International Turbo Commander 690B, in for a landing at Tweed New Haven Airport in rainy weather just before noon when the plane struck two small homes, engulfing them in flames. The aircraft's left wing lodged in one house and its right wing in the other.
As the children's mother yelled for help from the front lawn, several people in the working-class neighborhood raced to rescue the children, but they were forced to turn back by the fire.
A neighbor, David Esposito, was among those who raced to help the children's mother. He said he ran into the upstairs of the house, where the woman believed her children were, but he couldn't find them after frantically searching a crib and closets. He returned downstairs to search some more, but he dragged the woman out when the flames became too strong.
The pilot's family had learned it was Bill Henningsgaard's plane through the tail number, said his brother, Blair Henninsgaard, the city attorney in Astoria, Ore.
In 2009, Bill Henningsgaard was flying from Astoria, Ore. with his 84-year-old mother to watch his daughter in a high school play when he crashed into the river as he tried to glide back to the airport. He and his mother, a former Astoria mayor, climbed out on a wing and were rescued.
Henningsgaard was a member of Seattle-based Social Venture Partners, a foundation that helps build up communities. The foundation extended its condolences to his wife and two daughters.
"There are hundreds of people that have a story about Bill - when he went the extra mile, when he knew just the right thing to say, how he would never give up. He was truly all-in for this community, heart, mind and soul," the foundation wrote Friday in a post on its website.
Paul Shoemaker of Social Venture Partners told The Seattle Times that Henningsgaard was "an incredibly good, real, honest man, for the community, for his family, for this world."
"The guy has already done so much for the world. And he was going to do so much more," he said.
Henningsgaard spent 14 years at Microsoft in various marketing and sales positions, according to his biography on Social Venture Partners website. He was a longtime board member at Youth Eastside Services, a Bellevue, Wash.-based agency that provides counseling and substance-abuse treatment, and led the organization's $10.7 million fundraising campaign for its new headquarters, which opened in 2008.
Associated Press writers Steven DuBois in Portland, Ore., Gene Johnson in Seattle and John Christoffersen in East Haven, Conn., contributed to this report.