<addressing all comments> Lies, damn lies, and statistics. The NH is that a plane has 1/10 [M * flights] failure rate. The odds of 2 failures in 20M flights fa

<addressing all comments> Lies, damn lies, and statistics. The NH is that a plane has 1/10 [M * flights] failure rate. The odds of 2 failures in 20M flights falling in same (random) stride of 150K flights are 150K/20M = 0.75%. [E: fixed numbers] [EE: yes, I admit this calculation is incorrect]