"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 coming 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, with its tail section coming to rest upside down.
Two children, ages 1 and 13, have been missing since the plane crashed into their home. As their 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.
Authorities said previously that as many as six people could have died in the crash, but East Haven Deputy Fire Chief Anthony Moscato said the four recovered late Friday are believed to be the only victims. On Saturday, crews removed charred sections of the plane as National Transportation Safety Board investigators worked to determine the cause of the crash.
The pilot's family 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.
The 10-seater plane, a Rockwell International Turbo Commander 690B, flew out of Teterboro Airport in New Jersey and crashed at 11:25 a.m., the Federal Aviation Administration said. Neighbors reported they did not near any engine noise immediately before the crash.
Tweed's airport manager, Lori Hoffman-Soares, said the pilot had been in communication with air traffic control and hadn't issued any distress calls.
"All we know is that it missed the approach and continued on," she said.
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.
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.
A vigil for the victims of the crash was planned for Saturday night in an East Haven park.
Associated Press writers Steven DuBois in Portland, Ore., Gene Johnson in Seattle and John Christoffersen in East Haven, Conn., contributed to this report.