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Some of that stuff you have to look at the NTSB database to find out the rest of the story. For instance, the third one down has an NTSB# provided with the report (some of the others I’ve looked at don’t have that so it would be a pain to look them up). Using that number, I found the actual NTSB report at http://www.ntsb.gov/aviationquery/brief2.aspx?ev_id=20090915X12034&ntsbno=ERA09LA523&akey=1

There it says this:

“The airplane was purchased by the owner, without an engine, from an operator located in Switzerland, on June 19, 2008. It was maintained under a continuous airworthiness maintenance program. At the time of the accident, the airplane had been operated for 10,182 hours.

The engine, serial number 17310, was purchased by the operator through Northstar Aerospace, Stroud, Oklahoma, during March 2008. According to an engine logbook entry, it was overhauled by Northstar Aerospace on October 21, 2008. The overhaul was also documented on an FAA airworthiness approval tag, dated February 22, 2007. No previous logbooks or engine history was provided to the current owner. A maintenance record dated September 3, 2002, revealed that the sun gear found on the accident engine was previously removed from another engine due to “spalled gear teeth planetary gear.” Mint Turbines LLC purchased the Northstar Aerospace Turbine Engine Service Group business on May 27, 2009.

The engine was installed on the accident airplane on May 1, 2009. At the time of the accident, the engine had been operated for about 7,620 hours since new, and 65 hours since overhaul.”

What the NTSB investigation focused on as the probable source of the problem was the sun gear, which ultimately was too melted for them to determine what caused the problem. But if I’m understanding it correctly, this overhauled engine was put into this aircraft without the overhauling company revealing to the aircraft owner that the sun gear had previously been removed from a different aircraft because it was broken (spalled). The company which had done the overhaul had sold the business by the time the NTSB conducted its investigation.

This was an old plane, in the first round of production of the Caravan (not a Grand Caravan). Interestingly, the crash happened on Sept 15, 2009 - a few days after the first Obama-regime anniversary of 9-11. The NTSB report says, “The pilot and the five passengers were employees of an industrial services company. At the time of the accident, the occupants were returning from a job site, and the airplane was transporting electric detonators, ammonium nitrate and nitromethane used for blasting operations.” This flight originated from Farmingdale Airport, which Wikipedia says is an airport used by general aviation to alleviate the burden on the airport in nearby NYC.

So every crash has a different story, and it would take major work to uncover them all, especially without seeing the actual NTSB report for each crash. One of the links you gave mentioned that part of the cause of one of the turbine failures was the failure of the operator to do proper inspection before flying that flight. I didn’t look up the NTSB report on that one; not sure if the link you gave provided an NTSB# for it. But stuff like that could explain the discrepancies between what you found and the list I had found regarding the number of engine failures the NTSB had found on properly-maintained commercial aircraft.

The NTSB doesn’t investigate crashes outside the US on non-US aircraft, but it DOES use other countries’ investigations when developing the safety requirements that commercial aircraft in the US have to obey - requirements that Makani Kai went above and beyond, according to Schuman. What those requirements might say about taking a broken part from one aircraft and putting it in another when overhauling an engine, I don’t know. I don’t know if there are standards for welding parts so that a broken part can be recertified, etc. That’s a bit beyond what I have the time to investigate. I’m also not a mechanic so I don’t know what role things like altitude, temperature, etc might have on these things. That stuff would have to be analyzed by a mechanic looking at the actual NTSB reports.

That last one that you mentioned, in Papua New Guinea, happened 2 weeks before the Fuddy crash. It said it was the official preliminary report, created 17 days after the crash. What struck me about that report is the detailed information it provided and the sources it named for those details. They knew and reported that stuff 17 days after the crash. Compare that with what the NTSB has reported now - 6-7 months later - on BOTH the Cessna crashes in Hawaii last year, within 50 days and 25 miles of each other.

In that Papua New Guinea crash, the pilot tried to land on a runway, couldn’t stop in time, crashed into trees, and ultimately flipped the plane when landing on a swamp. But the pilot was able to get out all but 3? (IIRC) of the 10 passengers, IIRC.