Making a quick guess that from '80-'08, Americans average 1MM flights/day, then odds of serious injury are ~1 in 95,000.
Odds of death are 1 in 9,333,333.
Assuming the possibility of taking 3 'average' flights/day, then you'd need to board flights non-stop for 8,523 years to die, on average. 88 years to be injured.
[1] - https://www.quora.com/How-many-people-fly-domestically-in-th...
Note that when looking at airline safety, you'll get misleading numbers if you go back too far. Safety has improved remarkably in the past couple of decades. In the 80s and 90s, a couple hundred fatalities per year was about typical in the US. In the last decade, the typical number is zero. There hasn't been a fatal crash involving an American airliner for over eight years, and you have to go all the way back to 2001 (November, not September) to find one involving a major American airline. Even if you include foreign airlines operating in the US, that only adds one fatal crash and three deaths to the recent total.
