There obviously is a need to say it again.
As I have just researched car statistics I know your 3 deaths per billion kilometres is a UK value. It is also not appropriate to compare distance travelled. Cruise is the safest part of the journey and covers the most distance.
Hours is also not really appropriate as most of the time is at cruise.
So that leaves one very telling statistic.
I am 2.925 times more likely to die flying than driving to and from the airport.
The only statistic that interests me is the one relating to my personal actions.
Therefore if I take a billion flights I am going to die 117 times. However if I take the car I will only die 40 times. That is quite clear to me which one is safer. Hours and kilometers are uninteresting.
Deaths per billion journey's:
Car: 40
Air: 117