Originally Posted by
MickG0105
For starters, the accident airplane, VH-NRX, is 25 years (and one month and seven days) old; not 26 years old as claimed in the article. NRX is Saab 340B serial number 291 - its first flight was 25 February 1992 and it entered commercial service with the US regional operator, Business Express Airlines, a month later on 25 March 1992.
. . .
Merely applying fleetwide statistics: If the airline has 25% spare engines, then the average engine has 20% fewer hours than the average plane. And the average plane might operate 1500 hours per year, perhaps 38K total hours, since new. Thus 30K hrs TT for the average engine. (No great claim to accuracy here, just a feel for the possible usage.)
If the failed shaft in fact ran 30K hrs with that fault, I might expect a special inspection (ultrasonic?) on high-time hardware in the fleet. It perhaps could even be done on-wing overnight.