[branchan]

How does 100k flights a day equal 2.4 millions hours of operation if each flight was on average 1 hour?

[grkvlt]

Yeah, confused. If we assume a two hour average flight, we get 365 * 2 * 100K = 73M hours/year so one failure per 1G hours is one failure in 1000 / 73 = ~14 years.