Crash in Indonesia
Join Date: Dec 1999
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NNT
I have made no speculation about the possible causes of the Garuda accident only posted the comment that, according to unofficial sources, the aircraft appears to have had fuel when it ditched.
As to the accident record of some of the Indonesian operators - that's just the point I indended - if you have to operate mainly in difficult terrain, in poor weather with limited aids then you can expect to have more accidents eg the stats show that, all else being equal, a non-precission approach is some 4 or 5 times more risky than a precission approach. You'll note that most of the accidents in Indonesia happen 'up country' at airports with very limited aids and in virtually every case no ILS.
I have made no speculation about the possible causes of the Garuda accident only posted the comment that, according to unofficial sources, the aircraft appears to have had fuel when it ditched.
As to the accident record of some of the Indonesian operators - that's just the point I indended - if you have to operate mainly in difficult terrain, in poor weather with limited aids then you can expect to have more accidents eg the stats show that, all else being equal, a non-precission approach is some 4 or 5 times more risky than a precission approach. You'll note that most of the accidents in Indonesia happen 'up country' at airports with very limited aids and in virtually every case no ILS.
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Preliminary story is both engine flame-out during descend inside Wx. at 23.000 ft. They never light up.Nor the APU (battery went flat during APU start attempt) Breaking clouds less than 8.000 ft.The crew decide ditching. 
Alba Gu Brath
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Just out of interest, how much water are the engines able to ingest before flame-out? I've been through some of the rain storms in Indonesia and it's like walking through Niagara Falls.
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It used to be about 12%, but after the Tacca incident they figured that the processing energy necessary inside the engine was more related to temperature and state e.g. is the water partially contained as a frozen state like hail.
Rain is pretty insignificant in the bypass section and the amount that gets into the compressor is affected by the fan spinner shape so 12% water entering the inlet does not translate to as much as 12% going into the compressor. However like I stated earlier if you put the water into the compressor as hail it's a lot more potent.
For rough ballpark numbers it would take in excess of 30% water alone in the compressor to cause the engine to spool down at flight idle. Of course if you manage to operate the engine at something lower than placarded flight idle these numbers are meaningless.
To put it in real world standards the CFM56 engine can sustained better than one in 100 million storms
Rain is pretty insignificant in the bypass section and the amount that gets into the compressor is affected by the fan spinner shape so 12% water entering the inlet does not translate to as much as 12% going into the compressor. However like I stated earlier if you put the water into the compressor as hail it's a lot more potent.
For rough ballpark numbers it would take in excess of 30% water alone in the compressor to cause the engine to spool down at flight idle. Of course if you manage to operate the engine at something lower than placarded flight idle these numbers are meaningless.
To put it in real world standards the CFM56 engine can sustained better than one in 100 million storms
Alba Gu Brath
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Lomapaseo
Informative, succinct and polite. Not three words that describe a lot of postings on Pprune but they definately describe that one of yours. Thank you very much.
It will be interesting to see the outcome of the inquiry into this accident.
BT
Informative, succinct and polite. Not three words that describe a lot of postings on Pprune but they definately describe that one of yours. Thank you very much.
It will be interesting to see the outcome of the inquiry into this accident.
BT
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<It will be interesting to see the outcome of the inquiry into this accident.>
I shouldn't be difficult to quickly assay the engines, for fuel, ash or compressor damage. If it's a fuel problem things will get very quite over there. If it's an ash problem, the phones will start ringing in all the international airline ops sections within hours.
If it's a weather problem, Boeing will be on this big time putting out reminders/restrictions with Airbus following suit.
I shouldn't be difficult to quickly assay the engines, for fuel, ash or compressor damage. If it's a fuel problem things will get very quite over there. If it's an ash problem, the phones will start ringing in all the international airline ops sections within hours.
If it's a weather problem, Boeing will be on this big time putting out reminders/restrictions with Airbus following suit.
