If I were an airline's insurer, I wouldn't want to gamble on the good luck lasting.
Objects drop from aircraft all the time, daily. It isn't generally newsworthy unless part of a larger story. And even then, only if the object is found and recognized as being from an aircraft. Small rocks also fall daily from space, probably more by weight than aircraft-related objects, yet virtually nobody ever gets hit by space rocks.
That being said, there was a russian spacecraft that disintegrated and hit someone house, in the middle of siberia bo less. So it does happen, but its freak ecen3ts territory.
https://en.wikipedia.org/wiki/Intelsat_708
https://arstechnica.com/science/2019/11/china-keeps-dropping...
"It has happened many times before, including most infamously in 1996 when a Long March 3B rocket veered off course shortly after a launch and crashed into a village. Chinese officials reported six dead from the accident, although Western sources have speculated that hundreds of Chinese citizens may have died in the accident."
Could you proofread and type correctly so we understand what you're saying? I can't read all of what you're saying.
Sort of. The possibility of some types of failure is anticipated in the design of other parts of the engine. But there are also inspection procedures in place to ensure that engine parts that might fail are replaced before they fail. A report on a previous incident in Feb 2018 (referred to upthread) says that the root cause was a cracked engine fan blade that should have been detected on a previous inspection but wasn't. Failures that are supposed to be prevented by inspection and replacement of parts are not necessarily also allowed for in other parts of the design. So it's quite possible that luck is involved here as well and that a future failure of this type could have much worse consequences.
(A380 "blade off" test, rare footage of giant engine failing)
No, they're not. Fan blade cracks are expected; and fan blades are inspected for cracks so that the blades can be replaced before they fail.
Yes, it's also true that, as a second line of defense, engine housings are designed to contain failed blades. But the overall risk of the system is calculated on the assumption that that is a second line of defense, not the only line of defense. In other words, it's calculated on the assumption that a fan blade failure in flight will not be due to a crack that could have been detected at the last inspection but wasn't. It's calculated on the assumption that a fan blade failure in flight will be due to some other root cause that nobody has ever seen before. In other words, we have second lines of defense because we don't presume that we know about all possible root causes for a given failure. We don't expect fan blades to fail, but just in case one does due to some root cause we didn't know about, we design an extra layer of protection.
But what happened here is that an inspection regime designed to catch a root cause we do know about, failed to catch it. That's not within the design parameters of the system.
You still are not addressing my point.
Of course inspections cannot be relied upon to prevent failures due to root causes that are not known prior to the incident.
But inspections are relied upon to prevent failures due to root causes that are known. And that's what failed to happen in this case.
Put it this way: by your argument, the NTSB's final report on this should be something along the lines of "this was an expected failure and the containment worked, so no corrective action needs to be taken". Do you really think that's what will happen?
Whereas by my argument, the NTSB's final report on this will be something along the lines of "the inspection process failed to properly catch a cracked fan blade, and corrective actions A, B, and C need to be taken to fix the process".