737-500 missing in Indonesia
Although broadly useful FR24 data is wildly inaccurate at the detail level. I've observed my own flights on FR24 in real time out of curiosity and some of the manouevres it showed would have broken up my aircraft and had me busting controlled airspace.
DaveReidUK
Just like the China Airlines Flight 006, 19 Feb 1985. In this case the aircraft was at 41000ft. It fell 30000ft in 2 and a half minutes. The pilot managed to recover his bearings and pulled out just in time.
https://admiralcloudberg.medium.com/...6-e8bbc6683018
Just like the China Airlines Flight 006, 19 Feb 1985. In this case the aircraft was at 41000ft. It fell 30000ft in 2 and a half minutes. The pilot managed to recover his bearings and pulled out just in time.
https://admiralcloudberg.medium.com/...6-e8bbc6683018
CAT1
Well said. I consult these forums far less regularly for same reasons. Although I have worked in aviation industry many years, including previously some accident investigation, I would like these forums to help share confirmed news and, where possible, some credible expert opinions. Sadly far too many people just offering speculation based on no credible experience and believing without any limitations some flight-radar data.
Well said. I consult these forums far less regularly for same reasons. Although I have worked in aviation industry many years, including previously some accident investigation, I would like these forums to help share confirmed news and, where possible, some credible expert opinions. Sadly far too many people just offering speculation based on no credible experience and believing without any limitations some flight-radar data.
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Pitch up moment
NWA SLF
The whole discussion about pitch-up tendency on B737's stems from why MCAS is needed on the MAX.
It has NOTHING to do with engine thrust. Is has to do with the position of the engines. Since the engines have moved forward on the MAX, (because they are to big to stay under the wing), they generate lift and thus pitch-up tendency at extremely high angles of attack. This is beyond certification limits for passenger aircraft (pre-stall behaviour), hence MCAS for the MAX. Absolutely no issue on the -500.
The whole discussion about pitch-up tendency on B737's stems from why MCAS is needed on the MAX.
It has NOTHING to do with engine thrust. Is has to do with the position of the engines. Since the engines have moved forward on the MAX, (because they are to big to stay under the wing), they generate lift and thus pitch-up tendency at extremely high angles of attack. This is beyond certification limits for passenger aircraft (pre-stall behaviour), hence MCAS for the MAX. Absolutely no issue on the -500.
Hadley Rille
"Although broadly useful FR24 data is wildly inaccurate at the detail level. I've observed my own flights on FR24 in real time out of curiosity and some of the manouevres it showed would have broken up my aircraft and had me busting controlled airspace."
If you're seeing erratic tracks for your own flights on FR24 then, assuming you're flying any commercial jet built in the last 30-odd years, you really need to be having a chat with your airline's Engineering department.
"Although broadly useful FR24 data is wildly inaccurate at the detail level. I've observed my own flights on FR24 in real time out of curiosity and some of the manouevres it showed would have broken up my aircraft and had me busting controlled airspace."
If you're seeing erratic tracks for your own flights on FR24 then, assuming you're flying any commercial jet built in the last 30-odd years, you really need to be having a chat with your airline's Engineering department.
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DaveReidUK
Do you work for FR24, Dave? You are defending them and their data every chance you get.
Weird data from FR24? I have seen this many times, even near major airports. I have seen aircraft flying below safe altitude right into mountains. Never happened. I have seen aircraft hanging in the air, then plunge down to the runway. Never happened. I have seen aircraft overshooting runways by miles.. Never happened. Aircraft backing in the air. Never happened. Aircraft suddenly gone. Never happened.
Yet, every time an accident happens, FR24 data is taken as 100% accurate. It can be wlldly inaccurate.
Do you work for FR24, Dave? You are defending them and their data every chance you get.
Weird data from FR24? I have seen this many times, even near major airports. I have seen aircraft flying below safe altitude right into mountains. Never happened. I have seen aircraft hanging in the air, then plunge down to the runway. Never happened. I have seen aircraft overshooting runways by miles.. Never happened. Aircraft backing in the air. Never happened. Aircraft suddenly gone. Never happened.
Yet, every time an accident happens, FR24 data is taken as 100% accurate. It can be wlldly inaccurate.
Then there is the possibility that the engine fell off on its own as the aircraft spiraled down, ala PA and TWA events. This typically results in flat impacts on non-running engines. Let's see what else turns up in the investigation.
Pegase Driver
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I totally agree with CAT1 , but every accident it is the same here : I call it "trial by FR24" and it is even worse when a spotter leaks the R/T ATC frequency then inevitably the "experts" prime interest is looking to blame individuals , preferably the crew or the controllers. .. Human nature I guess. When the first Investigation reports comes out their wild theories are debunked but that does not deter them to start again at the next accident . The Ted Cruz of PPRuNe...
For info, Jakarta ACC has a relatively new radar , and together with the APP one have already a very accurate track and Altitude read outs. No need of FR24.
For info, Jakarta ACC has a relatively new radar , and together with the APP one have already a very accurate track and Altitude read outs. No need of FR24.
Administrator
There is a report that the black boxes have been located. They have not yet, it seems, been retrieved.
Navy divers are confident that they will be able retrieve the two flight recorders when the search operation resumes on Monday.
Aircraft parts and human remains have been found.
The Sriwijaya Air Boeing 737 was carrying 62 people when it vanished from radar on its journey to Borneo.
"We have located the position of the black boxes, both of them," said Soerjanto Tjahjono, head of Indonesia's transport safety committee, quoted by AFP earlier on Sunday.
"Divers will start looking for them now and hopefully it won't be long before we get them."
Aircraft parts and human remains have been found.
The Sriwijaya Air Boeing 737 was carrying 62 people when it vanished from radar on its journey to Borneo.
"We have located the position of the black boxes, both of them," said Soerjanto Tjahjono, head of Indonesia's transport safety committee, quoted by AFP earlier on Sunday.
"Divers will start looking for them now and hopefully it won't be long before we get them."
Weird data from FR24? I have seen this many times, even near major airports. I have seen aircraft flying below safe altitude right into mountains. Never happened. I have seen aircraft hanging in the air, then plunge down to the runway. Never happened. I have seen aircraft overshooting runways by miles.. Never happened. Aircraft backing in the air. Never happened. Aircraft suddenly gone. Never happened.
Now you are saying FR24 data can’t be relied on, but you also produce graphs based on this data?
Administrator
Dear Posters:
We have had sufficient digression, in terms of post count, into the reliabilty of FR24 (both pro and con).
While this will provide some useful information to novices reading through the discussion here, any further digression is no longer welcome in this thread.
FR24's quality is not this thread's topic.
We have had sufficient digression, in terms of post count, into the reliabilty of FR24 (both pro and con).
While this will provide some useful information to novices reading through the discussion here, any further digression is no longer welcome in this thread.
FR24's quality is not this thread's topic.
Getting back to the topic of the thread, I can only think of four prior instances in the past 15 years where a large jet airliner fell out of the sky without any communication from the crew and the cause was not ultimately linked to third party interference. In all four cases icing or some recoverable technical fault led to a complete loss of control due to a lack of basic airmanship. Two of these happened in Indonesia... (and NO, I'm not speaking of Lionair). Just saying...
andrasz
Can you define what you mean by "third party interference" ? There is one other obvious instance not included in your four icing/technical cases, but which also didn't involve a third party.
No suggestion that there were any similarities to this latest event, just interested in your definition.
Can you define what you mean by "third party interference" ? There is one other obvious instance not included in your four icing/technical cases, but which also didn't involve a third party.
No suggestion that there were any similarities to this latest event, just interested in your definition.
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Ethiopean 737-800 fell out of the skies after climb out from BEY. They lost control most likely due to CB activity. Happened around 8000 ft.
West Air Sweden nose dived into the ground (CRJ 200) from cruise level because of IRS failure that messed up the captains PFD.
Loss of control is not that unusual and why a lot of training has focused on this recently.
West Air Sweden nose dived into the ground (CRJ 200) from cruise level because of IRS failure that messed up the captains PFD.
Loss of control is not that unusual and why a lot of training has focused on this recently.
DaveReidUK
Bomb, missile, etc. Indeed I did miss ET at BEY, that makes it five.I have purposefully excluded the instances where the pilot willfully flew into the ground, those were in full control. In case of the West Air Sweden CRJ the pilots did communicate.
Bomb, missile, etc. Indeed I did miss ET at BEY, that makes it five.I have purposefully excluded the instances where the pilot willfully flew into the ground, those were in full control. In case of the West Air Sweden CRJ the pilots did communicate.
Last edited by andrasz; 11th Jan 2021 at 18:50.
It’s a theory, but loading-related accidents pretty reliably happen within seconds of attempting to fly (see 747 at Bagram as an example), as that’s when the greatest body angles occur and where you are most vulnerable to shifting/wrong cargo, mis-set trim, etc. Also, I suspect manufacturers take fuel movement into account when designing loading limits; manual and automatic load sheets certainly take account of CG movement during fuel usage to make sure it doesn’t cause problems at any stage of flight.
From our local paper,
Some one living in the tropics saying it was heavy rain would indicate, to me at least, it was HEAVY.
Fisherman Hendrik said he had been fishing in heavy rain near Lancang Island when he heard a "loud sound about fifty metres away from me and a big fall which caused big waves in the water".
"I was scared and had to focus on keeping my boat stable but after the water calmed, i saw many pieces of trash".
"I was scared and had to focus on keeping my boat stable but after the water calmed, i saw many pieces of trash".
As many have said, it's too early to speculate. There's clearly been a loss of control that could be mechanically related, weather related, crew related or a combination of all three, or some other completely different cause, but none of us know at this point in time. Having said that, the extract below has always stayed with me as an example of how easily control can be lost when there is a break down in crew coordination. Not saying that's happened here, but sometimes the ease with which a major accident occurs following a minor problem is quite unbelievable & AF447 is the classic example of that...
The DFDR analysis showed that the aircraft was in cruise at FL 350 with the autopilot engaged. The autopilot was holding 5 degrees left aileron wheel in order to maintain wings level. Following the crew’s selection of the number-2 (right) IRS Mode Selector Unit to ATT (Attitude) mode, the autopilot disengaged. The control wheel (aileron) then centered and the aircraft began a slow roll to the right. The aural alert, BANK ANGLE, sounded as the aircraft passed 35 degrees right bank.
The DFDR data showed that roll rate was momentarily arrested several times, but there was only one significant attempt to arrest the roll. Positive and sustained roll attitude recovery was not achieved. Even after the aircraft had reached a bank angle of 100 degrees, with the pitch attitude approaching 60 degrees aircraft nose down, the pilot did not roll the aircraft’s wings level before attempting pitch recovery in accordance with standard operating procedures. The aircraft reached 3.5g, as the speed reached Mach 0.926 during sustained nose-up elevator control input while still in a right bank. The recorded airspeed exceeded Vdive (400 kcas), and reached a maximum of approximately 490 kcas just prior to the end of recording.
The DFDR data showed that roll rate was momentarily arrested several times, but there was only one significant attempt to arrest the roll. Positive and sustained roll attitude recovery was not achieved. Even after the aircraft had reached a bank angle of 100 degrees, with the pitch attitude approaching 60 degrees aircraft nose down, the pilot did not roll the aircraft’s wings level before attempting pitch recovery in accordance with standard operating procedures. The aircraft reached 3.5g, as the speed reached Mach 0.926 during sustained nose-up elevator control input while still in a right bank. The recorded airspeed exceeded Vdive (400 kcas), and reached a maximum of approximately 490 kcas just prior to the end of recording.
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Not questioning the basic premise of your post but the quoted excerpt doesn’t sound like the AF447 scenario at all. Is it?
Thought it was stalled all the way into the sea.
Thought it was stalled all the way into the sea.
Its not an extract of the AF447 report but the AF447 accident is listed as the classic example of loss of control where the crew should have been able to handle the problem. I am not sure which incident the extract refers to. Its never too early to speculate but probably it is too early to have any factual information.