My great-grandfather was on that flight, on some kind of business trip, and was seated near Grant. According to what he wrote, Grant was a fairly friendly guy before he took over the plane.
I didn't find out he was on the flight until years after he died, but luckily there were numerous newspaper interviews and and an eight page account of the event written by him preserved by the rest of the family.
It really was something for it's time, wasn't it? Glad it had a good outcome.