But was he the kind of person who took unnecessary risks? Was he reckless? 60 Minutes II Correspondent Dan Rather asked that question of those who ought to know, the people he chose to be with during a part of his life we've heard very little about: his adventures.
Since he was a boy, John F. Kennedy Jr. had wanted to fly.
"He really loved to fly the power parachute," says Lloyd Howard, who taught him how to use the device. "So his adventurous spirit I think led him to do things that were new and that he had not done before."
Howard remembers Kennedy's first flight, in Albany, New York: "He didn't act nervous. In fact, he acted like he was very anxious to get in the air. We had gone through training very carefully, and made sure he understood everything. And I think he felt comfortable."
Howard says that his student liked the privacy of flying: "He liked being free. He liked being away from it. That was one reason he really enjoyed himself here; he was away from it all. Flying, he was away from it. And I think that's as good a way of putting it as anyI think it gave him freedom. Freedom from press, freedom from pictures, freedom from people wanting autographs, freedom from being pressed by the things around him."
Later, Kennedy went to Howard's headquarters in Indiana. His wife Carolyn joined him. He bought a machine built for two. They flew it in 1997 on the anniversary of John's father's assassination. "We tried to make it a day that was not to do anything in any way to remind him," says Howard. "He wanted it to be a happy day."
John wanted Carolyn to share his love of flying.
Kennedy had tested his wings earlier, as 60 Minutes Contributor Christiane Amanpour -- a close friend from college days -- told Mike Wallace. She says he "loved flying."
College fraternity brother Richard Weise saw early on that John Kennedy Jr. was always searching for the next adventure. "Our common interest was sports," says Weise, "and really since college to the present day it would not be unusual on a fall day or on a spring or winter day to be playing touch football in the park during the weekends."
But his greatest adventures were out of the public eye, far beyond the longest lens of any photographer. "He took a big bite out of life," says Jim Alden, who shared his love for sea kayaking. "He would live the kind of things that a lot of us would love to do. And I was lucky enough to share some of those moments."
Alden says that his friend saw kayaking, which can be strenuous, as a release from thpressures of everyday life.
In 1992, Kennedy wrote an article about a trip he took near the North Pole with Alden and two other friends.
"This trip was to be different -- four desk jockeys in search of manageable danger," he wrote. "It was tough. . . After paddling 125 miles in eight days we washed out a mere 10 miles from our destination. We suspected the workings of an unseen hand that controlled the pace from the start, teasing us until the very end, then hammering us in the final round. But we got what we had come for: some laughs, some thrills and a few sea stories."
Alden remembers that during the trip, one kayaker rolled over and John quickly paddled over and pulled him out of the water. He was cool under pressure, Alden says.
Kennedy didn't just fly and kayak. Beginning as a teenager, he loved to scuba dive -- with world famous treasure hunter Barry Clifford. Kennedy worked as a member of his crew. Over the years, Kennedy joined Clifford searching for old wrecks, and sometimes finding danger.
"He was the kind of person that -- and I've seen a lot of people in the business -- he was just someone you could trust to get you out of a situation, and he would do at any cost." Recently, the pair were diving, and Clifford got tangled up in some line and ran out of air. Kennedy shared his mouthpiece with Clifford until he could get untangled. "John just reacted very calmly," he says.
His friends -- those who knew him best -- all tell us the same thing: while Kennedy loved adventure, he never took unnecessary risks.
Clifford disagrees, strongly, with the idea that Kennedy took unnecessary risks. "I never knew him to take risks. John wasn't like that," he says. Amanpour says the same thing.
So as a man of caution, why did Kennedy take off into the haze on Friday night? In these last few days, many strangers were quick to make judgments. But his close friends, who are reluctant to share their insights, may know best what was going on when Kennedy took off on his final adventure:
"I believe that his preparation was meticulous," Alden says. "And I keep thinking that there had to be some external factor involved. He's so careful about what he does. And to be honest with you, to this day I still have not completely accepted that he's gone. If anyone in the world could find a way out of this mess he's the guy."
"I don't really believe there was a reckless bone in John," Howard says. "I think he was very careful in what he did. He was no Chuck Yeager or somebody that took chances."
In the end, they say, John Kennedy Jr. seemed more interested in adventure and experience than in danger for the sake of danger.
Produced by David Kohn;