4 ms·

While the failure rate is certainly not zero (Hudson miracle, Qantas A380 engine explosion) jet engines are so extremely reliable that I doubt such statistics c

While the failure rate is certainly not zero (Hudson miracle, Qantas A380 engine explosion) jet engines are so extremely reliable that I doubt such statistics can even be found. There are additional safeguards when it comes to a jetliners powerplants. For example: The oil is never exchanged at the same time in all engines on a plane. I fail to see, however, what this has to do with burning batteries on a plane. A fire on a plane in flight is one of the worst imaginable scenarios, while the chances to land a plane without engine power are actually quite good. Unless you're in the middle of an ocean, that is.

mikeash 13y ago
Jet engines fail with decent regularity. It's not exactly common, but nor is it too rare to measure. For example, this claims a failure rate of about once per thirty years: http://www.airbus.com/fileadmin/media_gallery/files/safety_library_items/AirbusSafetyLib_-FLT_OPS-SUPP_TECH-SEQ07.pdf http://www.airbus.com/fileadmin/media_gallery/files/safety_l... Which, based on the number flying regularly, means there's an in-flight failure happening somewhere in the world every few days or so. There is a reason that every airliner of appreciable size has two engines or more. The 787 is rated to fly up to three hours away from the nearest airport. A gliding airliner will be lucky to make a tenth of that distance.
icegreentea 13y ago
This Airbus documents suggests a failure rate of of <1 per 100,000 flight hours [1]. (just an FYI, pretty increasing. 40 fold decrease since start of the jet liner era). I think the point he was trying to make is that while Boeing's actions clearly do not reduce the risk dangerous battery fire to zero, Boeing not only does not have to reduce it to zero, but really there should be no expectation that it be reduced to zero, given that we already fly accepting some sort of failure rate on the engine. This stems from the original posters implication that Boeing just used some sort of cheap hack fix so they could stem the deluge of bad PR and start making money again - with the further implication that the actions taken are a cheap hack fix since they clearly do not reduce risk to zero. [1] http://www.airbus.com/fileadmin/media_gallery/files/safety_library_items/AirbusSafetyLib_-FLT_OPS-SUPP_TECH-SEQ07.pdf http://www.airbus.com/fileadmin/media_gallery/files/safety_l...
neurotech1 13y ago
While the statistical failure rate is quite low, with the total hours flown, they still happen regularly. http://avherald.com/h?search_term=engine+shut+down&opt=6144&dosearch=1 http://avherald.com/h?search_term=engine+shut+down&opt=6... A contained battery overtemp failure is not a big deal, but an uncontained battery thermal runaway is a huge safety issue. Qantas A380 was a extremely rare uncontained failure, the most serious type of malfunction. The Hudson A320 was a double engine failure, also is extremely rare. There have been incidents of maintenance SNAFU causing oil loss in all 3 engines on a DC-10, but ETOPS rules for twin aircraft prevent such incidents from maintenance causes. An uncontrolled fire on a plane is a worst case scenario, and ironically in some cases a water ditching might actually be advisable. A contained and extinguished engine fire in one engine is not nearly as critical.

mikeash 13y ago

Jet engines fail with decent regularity. It's not exactly common, but nor is it too rare to measure. For example, this claims a failure rate of about once per thirty years: http://www.airbus.com/fileadmin/media_gallery/files/safety_library_items/AirbusSafetyLib_-FLT_OPS-SUPP_TECH-SEQ07.pdf http://www.airbus.com/fileadmin/media_gallery/files/safety_l... Which, based on the number flying regularly, means there's an in-flight failure happening somewhere in the world every few days or so. There is a reason that every airliner of appreciable size has two engines or more. The 787 is rated to fly up to three hours away from the nearest airport. A gliding airliner will be lucky to make a tenth of that distance.

icegreentea 13y ago

This Airbus documents suggests a failure rate of of <1 per 100,000 flight hours [1]. (just an FYI, pretty increasing. 40 fold decrease since start of the jet liner era). I think the point he was trying to make is that while Boeing's actions clearly do not reduce the risk dangerous battery fire to zero, Boeing not only does not have to reduce it to zero, but really there should be no expectation that it be reduced to zero, given that we already fly accepting some sort of failure rate on the engine. This stems from the original posters implication that Boeing just used some sort of cheap hack fix so they could stem the deluge of bad PR and start making money again - with the further implication that the actions taken are a cheap hack fix since they clearly do not reduce risk to zero. [1] http://www.airbus.com/fileadmin/media_gallery/files/safety_library_items/AirbusSafetyLib_-FLT_OPS-SUPP_TECH-SEQ07.pdf http://www.airbus.com/fileadmin/media_gallery/files/safety_l...

neurotech1 13y ago

While the statistical failure rate is quite low, with the total hours flown, they still happen regularly. http://avherald.com/h?search_term=engine+shut+down&opt=6144&dosearch=1 http://avherald.com/h?search_term=engine+shut+down&opt=6... A contained battery overtemp failure is not a big deal, but an uncontained battery thermal runaway is a huge safety issue. Qantas A380 was a extremely rare uncontained failure, the most serious type of malfunction. The Hudson A320 was a double engine failure, also is extremely rare. There have been incidents of maintenance SNAFU causing oil loss in all 3 engines on a DC-10, but ETOPS rules for twin aircraft prevent such incidents from maintenance causes. An uncontrolled fire on a plane is a worst case scenario, and ironically in some cases a water ditching might actually be advisable. A contained and extinguished engine fire in one engine is not nearly as critical.