Ethiopian airliner down in Africa
Lion Air was deluged with heavy raid the night before the tragedy. Yes, I'm still looking for multiple glitches, that when combined cause chaos.
Those graphs seem too similar not to be very closely connected, but the similarity might be partly caused by human interpretation and resultant handling and not entirely by glitch sequences.
Those graphs seem too similar not to be very closely connected, but the similarity might be partly caused by human interpretation and resultant handling and not entirely by glitch sequences.
-GY
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Trimming the plane for neutral stick force is part of safely trying to get back to the ground. This is a fundamental airplane flying concept since the 172 presolo days. Literally lesson one.
To decouple pilot controls from aircraft control surfaces may after all not be a very clever idea.
After reading through all 12 of the AF 447 threads, I came away with the impression that some people felt that the A in BEA stood for Airbus.
Most probably the Boeing MCAS will also be mentioned as "not so clever idea" in the final reports, without identifying it as cause or contributing factor... So those reading only that part of the report will probably claim that the B in NTSB stands for Beoeing...
Need to be specific about what you mean by "duplicate the problem".
If you know what will hapen and why it happens, if you are prepared, it is a totally different scenarion.
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From The New York Times:
ADDIS ABABA, Ethiopia — The captain of a doomed Ethiopian Airlines jetliner faced an emergency almost immediately after takeoff from Addis Ababa, requesting permission in a panicky voice to return after three minutes as the aircraft accelerated to abnormal speed, a person who reviewed air traffic communications said Thursday.
“Break break, request back to home,” the captain told air traffic controllers as they scrambled to divert two other flights approaching the airport. “Request vector for landing.”
Controllers also observed that the aircraft, a new Boeing 737 Max 8, was oscillating up and down by hundreds of feet — a sign that something was extraordinarily wrong.
All contact between air controllers and the aircraft, Ethiopian Airlines Flight 302 to Nairobi, was lost five minutes after it took off on Sunday, the person said.
The person who shared the information, speaking on the condition of anonymity because the communications have not been publicly released, said the controllers had concluded even before the captain’s message that he had an emergency.
The account of the cockpit communications shed chilling new detail about the final minutes before the plane crashed, killing all 157 people aboard. The crash, which has led to a worldwide grounding of Max 8s, was the second for the best-selling Boeing aircraft in less than five months.
Regulatory authorities in the United States and Canada say similar patterns in the trajectories of both planes may point to a common cause for the two crashes. But they cautioned that no explanation had been ruled out yet, and said the planes might have crashed for different reasons.
The new disclosures about the last moments of Flight 302 came as pilots were discussing what they described as the dangerously high speed of the aircraft after it took off from Addis Ababa’s Bole International Airport.
Pilots were abuzz over publicly available radar data that showed the aircraft had accelerated far beyond what is considered standard practice, for reasons that remain unclear.
“The thing that is most abnormal is the speed,” said John Cox, an aviation safety consultant and former 737 pilot.
“The speed is very high,” said Mr. Cox, a former executive air safety chairman of the Air Line Pilots Association in the United States. “The question is why. The plane accelerates far faster than it should.”
Ethiopian Airlines officials have said the crew of Flight 302 reported “flight control” problems to air traffic controllers a few minutes before contact was lost. The new account of communications between air traffic controllers and the pilot, Yared Getachew, who had 8,000 hours of flying experience, provides much more information about what was happening in the cockpit.
Within one minute of Flight 302’s departure, the person who reviewed communications said, Captain Getachew reported a “flight control” problem in a calm voice. At that point, radar showed the aircraft’s altitude as being well below what is known as the minimum safe height from the ground during a climb.
Within two minutes, the person said, the plane had climbed to a safer altitude, and the pilot said he wanted to stay on a straight course to 14,000 feet.
Then the controllers observed the plane going up and down by hundreds of feet, and it appeared to be moving unusually fast, the person said. The controllers, the person said, “started wondering out loud what the flight was doing.”
Two other Ethiopian flights, 613 and 629, were approaching from the east, and the controllers, sensing an emergency on Flight 302, ordered them to remain at higher altitudes. It was during that exchange with the other planes, the person said, that Captain Getachew, with panic in his voice, interrupted with his request to turn back.
Flight 302 was just three minutes into its flight, the person said, and appeared to have accelerated to even higher speeds, well beyond its safety limits.
Cleared by the controllers to turn back, Flight 302 turned right as it climbed further. A minute later, it disappeared from the radar over a restricted military zone.
The disaster drew immediate comparisons to the October crash of another Boeing 737 Max 8, operated by Lion Air, in Indonesia. Both took place soon after takeoff, and the crews of both planes had sought to return to the airport.
The possibility that the two crashes had a similar cause was central to regulators’ decision to ground all 737 Maxes, a family of planes that entered passenger service less than two years ago.
After the Indonesia crash, a new flight-control system meant to keep the jet from stalling was suspected as a cause. In both cases, pilots struggled to control their aircraft.
The investigation of the Ethiopian crash is still in its early stages, and safety regulators have noted that it is too soon to draw conclusions about the cause. The so-called black boxes, voice and flight data recorders that contain more detailed information about the Ethiopian flight’s final moments, arrived in France on Thursday for analysis.
Since the Indonesia crash, Boeing has been working on a software update for the 737 Max jets, expected by April. But the company and the Federal Aviation Administration face new questions over whether there should have been more pilot training as airlines added the new models to their fleets.
On Wednesday, the chairman of the transportation committee in the House of Representatives said he would investigate the F.A.A.’s certification of the 737 Max, including why the regulator did not require more extensive training.
Boeing 737 Max Hit Trouble Right Away, Pilot’s Tense Radio Messages Show
March 14, 2019
ADDIS ABABA, Ethiopia — The captain of a doomed Ethiopian Airlines jetliner faced an emergency almost immediately after takeoff from Addis Ababa, requesting permission in a panicky voice to return after three minutes as the aircraft accelerated to abnormal speed, a person who reviewed air traffic communications said Thursday.
“Break break, request back to home,” the captain told air traffic controllers as they scrambled to divert two other flights approaching the airport. “Request vector for landing.”
Controllers also observed that the aircraft, a new Boeing 737 Max 8, was oscillating up and down by hundreds of feet — a sign that something was extraordinarily wrong.
All contact between air controllers and the aircraft, Ethiopian Airlines Flight 302 to Nairobi, was lost five minutes after it took off on Sunday, the person said.
The person who shared the information, speaking on the condition of anonymity because the communications have not been publicly released, said the controllers had concluded even before the captain’s message that he had an emergency.
The account of the cockpit communications shed chilling new detail about the final minutes before the plane crashed, killing all 157 people aboard. The crash, which has led to a worldwide grounding of Max 8s, was the second for the best-selling Boeing aircraft in less than five months.
Regulatory authorities in the United States and Canada say similar patterns in the trajectories of both planes may point to a common cause for the two crashes. But they cautioned that no explanation had been ruled out yet, and said the planes might have crashed for different reasons.
The new disclosures about the last moments of Flight 302 came as pilots were discussing what they described as the dangerously high speed of the aircraft after it took off from Addis Ababa’s Bole International Airport.
Pilots were abuzz over publicly available radar data that showed the aircraft had accelerated far beyond what is considered standard practice, for reasons that remain unclear.
“The thing that is most abnormal is the speed,” said John Cox, an aviation safety consultant and former 737 pilot.
“The speed is very high,” said Mr. Cox, a former executive air safety chairman of the Air Line Pilots Association in the United States. “The question is why. The plane accelerates far faster than it should.”
Ethiopian Airlines officials have said the crew of Flight 302 reported “flight control” problems to air traffic controllers a few minutes before contact was lost. The new account of communications between air traffic controllers and the pilot, Yared Getachew, who had 8,000 hours of flying experience, provides much more information about what was happening in the cockpit.
Within one minute of Flight 302’s departure, the person who reviewed communications said, Captain Getachew reported a “flight control” problem in a calm voice. At that point, radar showed the aircraft’s altitude as being well below what is known as the minimum safe height from the ground during a climb.
Within two minutes, the person said, the plane had climbed to a safer altitude, and the pilot said he wanted to stay on a straight course to 14,000 feet.
Then the controllers observed the plane going up and down by hundreds of feet, and it appeared to be moving unusually fast, the person said. The controllers, the person said, “started wondering out loud what the flight was doing.”
Two other Ethiopian flights, 613 and 629, were approaching from the east, and the controllers, sensing an emergency on Flight 302, ordered them to remain at higher altitudes. It was during that exchange with the other planes, the person said, that Captain Getachew, with panic in his voice, interrupted with his request to turn back.
Flight 302 was just three minutes into its flight, the person said, and appeared to have accelerated to even higher speeds, well beyond its safety limits.
Cleared by the controllers to turn back, Flight 302 turned right as it climbed further. A minute later, it disappeared from the radar over a restricted military zone.
The disaster drew immediate comparisons to the October crash of another Boeing 737 Max 8, operated by Lion Air, in Indonesia. Both took place soon after takeoff, and the crews of both planes had sought to return to the airport.
The possibility that the two crashes had a similar cause was central to regulators’ decision to ground all 737 Maxes, a family of planes that entered passenger service less than two years ago.
After the Indonesia crash, a new flight-control system meant to keep the jet from stalling was suspected as a cause. In both cases, pilots struggled to control their aircraft.
The investigation of the Ethiopian crash is still in its early stages, and safety regulators have noted that it is too soon to draw conclusions about the cause. The so-called black boxes, voice and flight data recorders that contain more detailed information about the Ethiopian flight’s final moments, arrived in France on Thursday for analysis.
Since the Indonesia crash, Boeing has been working on a software update for the 737 Max jets, expected by April. But the company and the Federal Aviation Administration face new questions over whether there should have been more pilot training as airlines added the new models to their fleets.
On Wednesday, the chairman of the transportation committee in the House of Representatives said he would investigate the F.A.A.’s certification of the 737 Max, including why the regulator did not require more extensive training.
Quote:
Originally Posted by cervo77
Then there are differences, and the Pilots should have been informed about the differences. Unfortunately the lion and Ethiopian's pilots have not had this chance
Then there are differences, and the Pilots should have been informed about the differences. Unfortunately the lion and Ethiopian's pilots have not had this chance
Quote:GebreMariam said the Ethiopian Airlines pilots had received additional training on the flight procedures involving the 737 MAX 8 after the Lion Air crash.
Apologies with the mess of the quoting above but the site doesn't help you multi-quote....
Channel 4 News (UK) has just screened an interview with a "Senior Ethiopian Pilot".
Note that: the interview was voice disguised and anonymous. The pilot did not state that then flew 737 MAX-8, or if they did, what experience they had on that airframe.
In the interview the pilot stated that the MCAS had not been taught to them [by Boeing]. He went on to talk about not being able to defeat the system by pulling on the stick. He did NOT mention adjusting trim [as a means to defeat the system].
Having read from the professionals above about having to use trim wheels or cutout switches to defeat MCAS, and NOT using the stick alone, my conclusion from the interview was that the pilot had NOT been trained in the correct procedures, or surely he would have mentioned it?
Of course it might be that C4 found a pilot that hadn't flown the MAX 8, but the C4 journalists are usually pretty professional and wouldn't put this interview forward if that were the case.
- GY
Within one minute of Flight 302’s departure, the person who reviewed communications said, Captain Getachew reported a “flight control” problem in a calm voice. At that point, radar showed the aircraft’s altitude as being well below what is known as the minimum safe height from the ground during a climb.
Something doesn’t seem to add up here.
- GY
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That is interesting. Maybe a CoG problem, or misconfigured T/O trim?
Or if they had an AOA sensor fault they get a stick shaker straight away, crew are startled and arrest pitch up, a/c rapidly accelerates and flies to trim, thus creating a little porpoising. Maybe they then clean it up and MCAS finishes them off.
No idea. Very keen to see the data as and when.
Or if they had an AOA sensor fault they get a stick shaker straight away, crew are startled and arrest pitch up, a/c rapidly accelerates and flies to trim, thus creating a little porpoising. Maybe they then clean it up and MCAS finishes them off.
No idea. Very keen to see the data as and when.
AOA sensor reliability?
Anyone know if the AOA sensors on the MAX are any different from the NG? If not, are their reliability issues with the NG AOA sensors?
Otherwise, what chance is there for another AOA sensor triggering a MCAS event just now, when there are thousands of NGs making daily flights with no issues?
It just doesn’t seem to make sense unless this is a new/different AOA sensor design, with a design flaw.
- GY
Otherwise, what chance is there for another AOA sensor triggering a MCAS event just now, when there are thousands of NGs making daily flights with no issues?
It just doesn’t seem to make sense unless this is a new/different AOA sensor design, with a design flaw.
- GY
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IMO, the day Alan Mulally left Boeing was the beginning of the end of "Working Together." I'm not surprised at Boeing's current situation. Look at the KC-46's being delivered with trash, and tools left in them. It's like WTF is going on? Seems like a dire situation IMO.
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Anyone know if the AOA sensors on the MAX are any different from the NG? If not, are their reliability issues with the NG AOA sensors?
Otherwise, what chance is there for another AOA sensor triggering a MCAS event just now, when there are thousands of NGs making daily flights with no issues?
It just doesn’t seem to make sense unless this is a new/different AOA sensor design, with a design flaw.
- GY
Otherwise, what chance is there for another AOA sensor triggering a MCAS event just now, when there are thousands of NGs making daily flights with no issues?
It just doesn’t seem to make sense unless this is a new/different AOA sensor design, with a design flaw.
- GY
its not the sensor - its the fubar software and dependance on a single sensor which gets switched from side to side dependant on aircraft power cycles, but which can without any comparison or error checking drive a horizontal stabilizer !
Interesting choice of words. One item from the FAA grounding order that is missing from most conversations:
"On March 13,2019,the investigation of the ET302 crash developed new information from the wreckage concerning the aircraft 's configuration just after takeoff that,..."
Salute!
Sorry, Garage, but MCAS doesn't care about altitude. With flaps up and AoA at a certain value or above and not in A/P it will activate unless we have been misinformed for 5 months. Not sure about main gear being up, but there has been a mention of "configuration" shortly after takeoff.
Gums sends...
Sorry, Garage, but MCAS doesn't care about altitude. With flaps up and AoA at a certain value or above and not in A/P it will activate unless we have been misinformed for 5 months. Not sure about main gear being up, but there has been a mention of "configuration" shortly after takeoff.
Gums sends...
Either it’s a different sensor, new with the MAX, or this could one of the universes rarest conincidences. Or the crash is unrelated.
- GY
Salute!
Sorry, Garage, but MCAS doesn't care about altitude. With flaps up and AoA at a certain value or above and not in A/P it will activate unless we have been misinformed for 5 months. Not sure about main gear being up, but there has been a mention of "configuration" shortly after takeoff.
Gums sends...
Sorry, Garage, but MCAS doesn't care about altitude. With flaps up and AoA at a certain value or above and not in A/P it will activate unless we have been misinformed for 5 months. Not sure about main gear being up, but there has been a mention of "configuration" shortly after takeoff.
Gums sends...
Pretty sure it is 1000 ft AGL, but I’m trying to find a definitive reference.
Respectfully, GY
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I've been a long time in read-only mode, felt it was time to contribute.
If I've read the second graph correctly, the 21 seconds is measured from 05:39:11Z to 05:39:32Z (per the FR24 data) - corresponding to 225 feet and 600 feet aal.
That seems rather low for the flaps to be fully retracted, for MCAS to kick in, and for 10 secs of manual trim to be completed.
It appears from the same data that ET302 had only just left the runway at 05:38:59Z or a few seconds earlier. From what we know about the system, is it really feasible that MCAS starts operating 12 seconds later?
Apologies if I've misunderstood something.
That seems rather low for the flaps to be fully retracted, for MCAS to kick in, and for 10 secs of manual trim to be completed.
It appears from the same data that ET302 had only just left the runway at 05:38:59Z or a few seconds earlier. From what we know about the system, is it really feasible that MCAS starts operating 12 seconds later?
Apologies if I've misunderstood something.
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But the fubar software only does something if the AOA sensor is broken. My point is rather obvious. If there are thousands of the SAME sensors working perfectly, day in, day out, on NGs all over the world, it’s very unlikely that two suddenly go wrong within a few months.
Either it’s a different sensor, new with the MAX, or this could one of the universes rarest conincidences. Or the crash is unrelated.
- GY
http://www.ata-divisions.org/S_TD/pd...ngtheB-787.pdf
see pages 40-41
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If there are any mx tech on here can you tell us if the Stab trim cut out switches are connected to the MCAS system ie will the switches in the cut out position actually stop the MCAS from trimming thanks
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The manual ones next to the trim wheel are. The ones at the column sensing a pull against the trim obviously aren‘t because the MCAS has to trim against a strong pull to maintain the desired positive stick force gradient.
@ Boeing boy
Our resident engineer , FCeng84, and the wiring diagrams show that the switches cut off the electric trim motor. Trim wheel still works.
"bumping the trim switches on the yoke stops MCAS. then it starts again after 5 seconds if the AoA is still high. You can clearl;y see this on the 610 accident flight data and preceding flight.
So no dedicated MCAS power switches. It's all in the FCC boxes, thence wires to the trim motor.
Gums...
P.S. still can't find an altitude restriction or enabling condition.
Our resident engineer , FCeng84, and the wiring diagrams show that the switches cut off the electric trim motor. Trim wheel still works.
"bumping the trim switches on the yoke stops MCAS. then it starts again after 5 seconds if the AoA is still high. You can clearl;y see this on the 610 accident flight data and preceding flight.
So no dedicated MCAS power switches. It's all in the FCC boxes, thence wires to the trim motor.
Gums...
P.S. still can't find an altitude restriction or enabling condition.