MAX’s Return Delayed by FAA Reevaluation of 737 Safety Procedures
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Well yes, granted the last two perhaps, though I don't see the A320 family getting re-engined for a second time.
But putting new powerplants on 5-10 year old designs hardly qualifies as "grandfathering" when compared to certificating 4 distinct generations of an aircraft over a 50-year period on the same TC.
But putting new powerplants on 5-10 year old designs hardly qualifies as "grandfathering" when compared to certificating 4 distinct generations of an aircraft over a 50-year period on the same TC.
Boeings clean sheet FSA (future small aircraft) single isle was not due until 2030...and the E series, is well, virtually dead.
Boeing brilliant concept to knee jerk the NMA, a 767 fuselage with composite wings....really?
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...and then, right as he disappeared, someone new appeared. Not quite as rabid about the pilots, but still careful to mention them at every opportunity, a fairly strong supporter of Boeing, but keen to mention their mistakes. One who seems to have inside information to make his points.
i think that understanding that blip will be a key on the investigation, however we (or I) do not even know if the FDR records directly the thumb switch or the signal is processed by the FCC before been transmitted to the FDR. Considering the latest setback due to processing failure, we might assume that the final seconds of the recording might not be accurate due to FCC micro processor failure, latency, delay....or can even speculate that the pilots were trying to manually electricaly trim butthe system was not responding to their commands.
furthermore, Mr. Yoko1 where on the checlk lists is stated not to retract flaps?
.
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However, Boeing's cock-up with the MAX has been so huge, so amazingly stupendously perplexingly attention-grabbing, that it has literally sucked all the oxygen away from any discussion other than BOEING BOEING BOEING, with perhaps a smidgen of FAA regulatory capture.
So when I say Ethiopian Airlines is getting a pass, I do mean they are getting a pass.
Thanks for your - voluminous - post, which however really adds nothing new. We know the pilots screwed up, pilots tend to at times. Whether Boeing or the airlines were responsible for the 300-odd deaths is of interest only to lawyers and accountants. Things have moved on.
What the accidents - irrespective of cause - have shown is that the MAX has inherent flaws that extend to the certification process and even possibly to earlier types. This, I would suggest, is of greater and longer-lasting interest to most people here than the isolated causes of two fatal accidents. Yes, pilot training is also a concern but that is a general issue not specific to the MAX. I would also suggest that it belongs on another thread not this one.
If that's not a reference simply to the pickle switch position, one would expect it to be described differently.
There is, of course, a separate FDR trace with the legend "Automatic Trim Command" and states described as "No Trim", "Trim Up - FCC" and "Trim Down - FCC".
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That particular FDR trace is pretty unambiguous - it's labelled "Manual (Electric) Trim Command" and has three possible states: "Trim Up - Man", "Trim Down - Man" and "No Trim".
If that's not a reference simply to the pickle switch position, one would expect it to be described differently.
There is, of course, a separate FDR trace with the legend "Automatic Trim Command" and states described as "No Trim", "Trim Up - FCC" and "Trim Down - FCC".
If that's not a reference simply to the pickle switch position, one would expect it to be described differently.
There is, of course, a separate FDR trace with the legend "Automatic Trim Command" and states described as "No Trim", "Trim Up - FCC" and "Trim Down - FCC".
How would expect those signals to be called anyhow if they were captured by e.g. the FCC and passed to the FDR by some a digital bus?
I don't know what I'd call them, but if there was a channel for them on the FDR I would expect there also to be a separate channel for raw pickle switch position, and the logical one to show on the trace readout would be the latter (as appears to be the case).
...and then, right as he disappeared, someone new appeared. Not quite as rabid about the pilots, but still careful to mention them at every opportunity, a fairly strong supporter of Boeing, but keen to mention their mistakes. One who seems to have inside information to make his points.
Glad I am not the only one to notice this
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I've done a lot of logging data analysis - not in aviation but in automotive though. We would often find data where state information was not consistent and people would say this state vector is not possible. That must be faulty data. In nearly all cases it could be clarified - no faulty data but delays in signal path here or not looking at raw data but somehow processed data there.
So if you could point me to some material where I could learn more about the FDR and what exactly it processes I would be thankful.
I think I recognize the software that printed those plots (NI Diadem) and of course those axis descriptions are assigned by whomever did the analysis on his convenience.
Personally I'm grateful that the Mods have allowed this particular thread to continue and not close it off as has happened to all the others. I think it is abundantly clear that some very interesting information has been shared since the thread was started, but I wish the Mods would use the stick whenever "pilot training" (or lack of it) gets mentioned and cull the post.
Alchad
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If all those datapoints should run one or two wires each directly to the FDR then the connection on the FDR would need to be humongously large. And there would be introduced a not insignificant additional risk for wire shorts due to the added number and lenghts of wire which in its own is a safety risk for the aircraft.
So I am thinking you are jumping to conclusions and is not really considering the different methods of collecting all these data. Letting the FCC and other electronic boxes send data to the FDR via a buss greatly reduces the complexity of collecting all those data. And the buss is there anyway, how else to cellect data about engine conditions, flight parameters like acceleration etc?
So I am in line with the others here questioning exactly how the thumb switch signal is collected. I would hazard a guess it is NOT collected by running one or two discrete wires from the thumb switches all the way to the FDR.
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Well, there is a large number, certainly in excess 100, of true/false datapoints recorded by the FDR, the manual trim up/trim down to be one of them where each (trim up, trim down) have its own true/false state.
If all those datapoints should run one or two wires each directly to the FDR then the connection on the FDR would need to be humongously large. And there would be introduced a not insignificant additional risk for wire shorts due to the added number and lenghts of wire which in its own is a safety risk for the aircraft.
So I am thinking you are jumping to conclusions and is not really considering the different methods of collecting all these data. Letting the FCC and other electronic boxes send data to the FDR via a buss greatly reduces the complexity of collecting all those data. And the buss is there anyway, how else to cellect data about engine conditions, flight parameters like acceleration etc?
So I am in line with the others here questioning exactly how the thumb switch signal is collected. I would hazard a guess it is NOT collected by running one or two discrete wires from the thumb switches all the way to the FDR.
If all those datapoints should run one or two wires each directly to the FDR then the connection on the FDR would need to be humongously large. And there would be introduced a not insignificant additional risk for wire shorts due to the added number and lenghts of wire which in its own is a safety risk for the aircraft.
So I am thinking you are jumping to conclusions and is not really considering the different methods of collecting all these data. Letting the FCC and other electronic boxes send data to the FDR via a buss greatly reduces the complexity of collecting all those data. And the buss is there anyway, how else to cellect data about engine conditions, flight parameters like acceleration etc?
So I am in line with the others here questioning exactly how the thumb switch signal is collected. I would hazard a guess it is NOT collected by running one or two discrete wires from the thumb switches all the way to the FDR.
.It's not to expect someone has manipulated or frauded something.
Interpreting digital data collected from various sources across different datalinks is extremely bitchy and overpapered by printouts like we have seen. It also requires extremely high skilled analysts - to the astonishment of many. What can go wrong with that beautiful continuous lines anyway
Therefore I would like to learn more about the FDRs architecture.
I've done a lot of logging data analysis - not in aviation but in automotive though. We would often find data where state information was not consistent and people would say this state vector is not possible. That must be faulty data. In nearly all cases it could be clarified - no faulty data but delays in signal path here or not looking at raw data but somehow processed data there.
So if you could point me to some material where I could learn more about the FDR and what exactly it processes I would be thankful.
I think I recognize the software that printed those plots (NI Diadem) and of course those axis descriptions are assigned by whomever did the analysis on his convenience.
I've done a lot of logging data analysis - not in aviation but in automotive though. We would often find data where state information was not consistent and people would say this state vector is not possible. That must be faulty data. In nearly all cases it could be clarified - no faulty data but delays in signal path here or not looking at raw data but somehow processed data there.
So if you could point me to some material where I could learn more about the FDR and what exactly it processes I would be thankful.
I think I recognize the software that printed those plots (NI Diadem) and of course those axis descriptions are assigned by whomever did the analysis on his convenience.
Well, there is a large number, certainly in excess 100, of true/false datapoints recorded by the FDR, the manual trim up/trim down to be one of them where each (trim up, trim down) have its own true/false state.
If all those datapoints should run one or two wires each directly to the FDR then the connection on the FDR would need to be humongously large. And there would be introduced a not insignificant additional risk for wire shorts due to the added number and lenghts of wire which in its own is a safety risk for the aircraft.
So I am thinking you are jumping to conclusions and is not really considering the different methods of collecting all these data. Letting the FCC and other electronic boxes send data to the FDR via a buss greatly reduces the complexity of collecting all those data. And the buss is there anyway, how else to cellect data about engine conditions, flight parameters like acceleration etc?
So I am in line with the others here questioning exactly how the thumb switch signal is collected. I would hazard a guess it is NOT collected by running one or two discrete wires from the thumb switches all the way to the FDR.
If all those datapoints should run one or two wires each directly to the FDR then the connection on the FDR would need to be humongously large. And there would be introduced a not insignificant additional risk for wire shorts due to the added number and lenghts of wire which in its own is a safety risk for the aircraft.
So I am thinking you are jumping to conclusions and is not really considering the different methods of collecting all these data. Letting the FCC and other electronic boxes send data to the FDR via a buss greatly reduces the complexity of collecting all those data. And the buss is there anyway, how else to cellect data about engine conditions, flight parameters like acceleration etc?
So I am in line with the others here questioning exactly how the thumb switch signal is collected. I would hazard a guess it is NOT collected by running one or two discrete wires from the thumb switches all the way to the FDR.
That's why FDAUs came along in the 1970s.
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If BA chose to implement this by reading in pickle switches in the FCC and transmitting to DFDR by datalink and we do now now that this FCC can have computational issues in "situations" (not satisfied with the news details at all) then we are right at the point why I would like to now exactly: Which box does A/D at which rate and post processing and which uplink to FDR at which rate and possibly via which gateways in between.
Last edited by BDAttitude; 30th Jun 2019 at 10:13.
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If BA chose to implement this by reading in pickle switches in the FCC and transmitting to DFDR by datalink and we do now now that this FCC can have computational issues in "situations" (not satisfied with the news details at all) then we are right at the point why I would like to now exactly: Which box does A/D with wich rate and post processing and which uplink to FDR with which rate and possibly which gateways in bewtween.
When MCAS is active, could there be any difference in the control of electric trim from the trim switches at the Captains side and the FO side?
The Lion air Captain was winding back the trim wheel for seconds. The FO who was watching this all the time suddenly decided to use only blips, looks strange.
-Sanish
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I have a stupid question, may be better to get it discounted early.
When MCAS is active, could there be any difference in the control of electric trim from the trim switches at the Captains side and the FO side?
The Lion air Captain was winding back the trim wheel for seconds. The FO who was watching this all the time suddenly decided to use only blips, looks strange.
-Sanish
When MCAS is active, could there be any difference in the control of electric trim from the trim switches at the Captains side and the FO side?
The Lion air Captain was winding back the trim wheel for seconds. The FO who was watching this all the time suddenly decided to use only blips, looks strange.
-Sanish
However the digital representation of th FOs trim signal in the captains FCC could be different if e.g. FOs trim signal is digitized by FOs FCC and sent via datalink. And if interlock relies on software not on logic in the motor assembly.
Big IFs that's why more transparency is needed.
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I have a stupid question, may be better to get it discounted early.
When MCAS is active, could there be any difference in the control of electric trim from the trim switches at the Captains side and the FO side?
The Lion air Captain was winding back the trim wheel for seconds. The FO who was watching this all the time suddenly decided to use only blips, looks strange.
-Sanish
When MCAS is active, could there be any difference in the control of electric trim from the trim switches at the Captains side and the FO side?
The Lion air Captain was winding back the trim wheel for seconds. The FO who was watching this all the time suddenly decided to use only blips, looks strange.
-Sanish
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I have a stupid question, may be better to get it discounted early.
When MCAS is active, could there be any difference in the control of electric trim from the trim switches at the Captains side and the FO side?
The Lion air Captain was winding back the trim wheel for seconds. The FO who was watching this all the time suddenly decided to use only blips, looks strange.
-Sanish
When MCAS is active, could there be any difference in the control of electric trim from the trim switches at the Captains side and the FO side?
The Lion air Captain was winding back the trim wheel for seconds. The FO who was watching this all the time suddenly decided to use only blips, looks strange.
-Sanish
I have another question: if the FDR trace is for the switches, why are there only two traces (Trim Up-Man and Trim Down-Man), instead of four: one pair for the captain switches and one pair for the FO switches?
In fact, if they wanted to, they could record even the position of the individual halves of each switch, and that would require 8 parameters to be recorded on the FDR (4 up, 4 down).
The fact that there are only two traces for manual electric trim, one for up and one for down, seems to indicate that those commands are recorded "closer" to the motors than the switches, at a point where it is not possible to differentiate between the sources of the commands, the captain's or the FO's switches, let alone their halves.
YOKO SAN; , training at a number of airlines is conducted under contract by the manufacturer. Including ET. Not sure how that relieves the OEM from a lousy bit of head work, nor, once again, do I see that the crew, 160 etc... are the cause of the malaise that has beset the industry. Blaming the messenger is common practice but not morally supportable, and doesn’t fix the problem, which is industry wide, consider AF447, FEDEX MD’s, UPS bus, etc, splashes at KJAX, KSFO, aluminium wrapping in DXB, sundry uglies short, long, off side, end etc of runways, not done by 160 hr pilots, and not done by any particular race, creed, color, accent or religion. The rules do not require more than a specific standard, don’t blame those that are trained by the system, blame the system, as stated enough times that this matter is becoming an infinite loop.
Pilot performance is the result not the cause of the system.
The 160mhrvpilot probably could have done with a little more tech info by the OEM, and that and associated training being denied him is not his fault, irrespective of how much you may be offended by that.
cheers.
Pilot performance is the result not the cause of the system.
The 160mhrvpilot probably could have done with a little more tech info by the OEM, and that and associated training being denied him is not his fault, irrespective of how much you may be offended by that.
cheers.
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wish we had a white hat hacker that could track down several of the pro-B posters mentioned earlier, tracing IPs and so forth and see what the real story is. It would be explosive if it could be showed that a major company put stooges out there undercover to steer a discussion in a certain direction. What other chatrooms is this going on on? If B are going to join the conversation here, why not do it openly? There's now a poster ryanairrecruiter answering questions in terms and endearment. So much more adult!
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