kgwilson Posted March 10, 2019 Posted March 10, 2019 An Ethiopian Airlines flight to Nairobi has crashed, leaving no survivors of the 149 passengers and eight crew members aboard, Ethiopia's state broadcaster has said. Key points: A spokesman said the plane crashed on its journey from Addis Ababa The airline is yet to release a statement Up to 157 people were onboard the Boeing 737 when it crashed The crash occurred after the plane experienced an "unstable vertical speed after take-off", Swedish flight-tracking website flightradar24 said. "Data from Flightradar24 ADS-B network show that vertical speed was unstable after take off," the organisation said on Twitter. Flight ET 302, a Boeing 737-800 MAX from Addis Ababa to Nairobi, lost control with air traffic controllers on the ground six minutes after take-off. https://www.abc.net.au/news/2019-03-10/ethiopian-airlines-flight-to-nairobi-crashes-with-157-people/10887840 It is too early to tell what happened but there must now be some serious questions about this model 737. The plane was only 3 months old.
tafisama Posted March 10, 2019 Posted March 10, 2019 Something is definitely wrong here.It will be interesting to hear what Boeing has to say.
Methusala Posted March 10, 2019 Posted March 10, 2019 This is a disaster for Boeing. It raises serious issues about the re-engining of the 737. It may require more than merely re-writing the pilot's manual.
Downunder Posted March 10, 2019 Posted March 10, 2019 The Lion-air crash in Indo was the same aircraft. Also about 3 months old and crashed shortly after take off as well.. We expect old aircraft to be the ones failing.... As said above, something is very wrong here.... Are we hitting a point where they are be coming so complex in operation, in the quest for efficiency, that it's starting to become detrimental to the reliability?
Roundsounds Posted March 10, 2019 Posted March 10, 2019 This is a disaster for Boeing. It raises serious issues about the re-engining of the 737. It may require more than merely re-writing the pilot's manual. You are correct, if this is an MCAS related problem, the crew will need to be trained and competent in performing Boeing’s published procedures. This is most likely an issue for the training providers, including recurrent training not just the initial type rating. It seems the second last crew to operate the aircraft involved in the Lion Air accident were able to deal with the problem. The problem appears to have been caused by a maintenance issue and not a manufacturers design issue. Whether the crew know what may have caused the fault will have no effect on how they deal with it. Boeing have a published procedure to deal with the Lion Air problem.
kgwilson Posted March 10, 2019 Author Posted March 10, 2019 Boeing may have a published procedure now. They didn't before the Lion Air crash.
Thruster88 Posted March 10, 2019 Posted March 10, 2019 Any aircraft with electric trim has the potential for a runaway trim event. It's up to the pilot to know how to disable it. The 737 has two switches that disable electric trim, there are two large manual trim wheels. I can't believe this accident has the same cause, the pilot's would have been all over it.
biggles Posted March 10, 2019 Posted March 10, 2019 An eyewitness told AFP the plane came down in flames. “The plane was already on fire when it crashed to the ground. The crash caused a big explosion,” Tegegn Dechasa recounted at the site littered with passenger belongings, human remains and aeroplane parts around a massive crater at the point of impact. “The plane was in flames in its rear side shortly before the crash. The plane was swerving erratically before the crash.”
planedriver Posted March 10, 2019 Posted March 10, 2019 I can't believe this accident has the same cause, the pilot's would have been all over it. However, we are all creatures of habit, If the PIC was not totally on top of new input requirements under certain conditions, the way he has done things for years flying similar, but different models, could cause issues handled by some, but not all who operate them. These days, everything gets more complicated, but in most things "simplicity is the essence of reliability" The Air France A330 issue with pitot's problem was fairly quickly overcome, and the skies are now full of them operating safely. Hopefully they get the 737-800 Max sorted quickly too. It would be devastating for a company like Boeing's reputation.
horsefeathers Posted March 10, 2019 Posted March 10, 2019 Lion air and latest crash had similar flight profiles, similar aircraft behaviour, similar (identical?) model aircraft, similar outcomes - high speed crash into sea/terrain. Data from FlightAware for ET302 showed terminal speed 383 knots,2600ft/minute decent, after fluctuations in height and speed. Seems like you can point to a similar cause between lion air and the latest crash 1
Methusala Posted March 11, 2019 Posted March 11, 2019 China has grounded their fleet replaced with older 800 series a/c. Captain was very experienced with 8000hrs. Unlikely that he was not aware of the Lion Air reports. A/c reported to be on fire as it descends. Catastrophe for Boeing. 1
kgwilson Posted March 11, 2019 Author Posted March 11, 2019 Any aircraft with electric trim has the potential for a runaway trim event. It's up to the pilot to know how to disable it. The 737 has two switches that disable electric trim, there are two large manual trim wheels. I can't believe this accident has the same cause, the pilot's would have been all over it. The 737 must be the only airliner left with cables connecting servo tabs for ailerons & elevators & trim as well it seems. With todays fly by wire multiple redundant systems I don't think that makes it any safer
Thruster88 Posted March 11, 2019 Posted March 11, 2019 The trim cut out switches can be seen just above the red 2. Press those, manually trim with the big black things like you would in a cessna, problem solved. There has to be more to this accident.
kgwilson Posted March 11, 2019 Author Posted March 11, 2019 This is probably one of the easiest & simplest functions in the cockpit. Presumably the manual over ride for the ailerons & elevator is just attached to the yoke assembly & if it needs to be used probably needs a bit of muscle? In the Lion air crash reports stated the pilots were struggling to bring the nose up. If they'd disabled the system & flew it like a Cessna I assume it would be "Problem Solved". 1
Thruster88 Posted March 11, 2019 Posted March 11, 2019 Runaway elevator trim is a scary thing https://www.atsb.gov.au/publications/investigation_reports/2015/aair/ao-2015-105/ It has more muscle than the pilot(s).
IBob Posted March 11, 2019 Posted March 11, 2019 You are correct, if this is an MCAS related problem, the crew will need to be trained and competent in performing Boeing’s published procedures. This is most likely an issue for the training providers, including recurrent training not just the initial type rating. It seems the second last crew to operate the aircraft involved in the Lion Air accident were able to deal with the problem. The problem appears to have been caused by a maintenance issue and not a manufacturers design issue. Whether the crew know what may have caused the fault will have no effect on how they deal with it. Boeing have a published procedure to deal with the Lion Air problem. While we have no idea yet what caused this latest accident........as an automation eng (retired), I find it hard to accept the idea of automation that, upon failure (for whatever reason) of one or two sensors, then flies the entire aircraft into the ground. A large part, often the largest part, of any automation, is dealing with all the what ifs. This (first event) seems to have been a massive failure in doing that. And I don't buy the idea that the remedy is crew training: quite apart from anything else, if the automation, connected to all available sensors and instruments, is unable to generate an appropriate and safe response, how on earth are the crew supposed to? 2 1
Methusala Posted March 11, 2019 Posted March 11, 2019 Already noted that it was on fire before impact. Points to more than runaway trim
red750 Posted March 12, 2019 Posted March 12, 2019 Aviation regulators in China and Indonesia have suspended flights using that model. Ethiopian Airlines, Cayman Airways and Comair, have also grounded their 737 Max 8 aircraft. US and Canadian airlines are continuing to fly them.
red750 Posted March 12, 2019 Posted March 12, 2019 Yahoo home page: Boeing 737 Max jets banned from flying in Australia after Ethiopian plane tragedy Aviation authorities have banned airlines from flying Boeing 737 Max jets in Australia after one of the planes crashed in Ethiopia, killing more than 150 people. The Ethiopian Airlines 737 MAX 8 fell from the sky minutes after take-off from Addis Ababa for Nairobi on Sunday killing 157 people on board. Australia’s Civil Aviation Safety Authority suspended two international airlines from flying their 737 MAXs to or from Australia on Tuesday.
red750 Posted March 12, 2019 Posted March 12, 2019 Malaysia has now joined the countries banning the Max8.
facthunter Posted March 12, 2019 Posted March 12, 2019 The being on fire aspect doesn't appear in informed reports.. .Being aware of how the( Automatic) pitch application works and the new C of G/ engine(s) location effect seems to be the crucial issue The "differences" between this and previous models was minimized as a sales pitch offering reduced off line times for pilots as a product advantage.. Nev
dsam Posted March 12, 2019 Posted March 12, 2019 While we have no idea yet what caused this latest accident........as an automation eng (retired), I find it hard to accept the idea of automation that, upon failure (for whatever reason) of one or two sensors, then flies the entire aircraft into the ground. A large part, often the largest part, of any automation, is dealing with all the what ifs. This (first event) seems to have been a massive failure in doing that. And I don't buy the idea that the remedy is crew training: quite apart from anything else, if the automation, connected to all available sensors and instruments, is unable to generate an appropriate and safe response, how on earth are the crew supposed to? Regarding automation failure, it defies belief that Boeing would design software that would fly the aircraft into the ground at considerable speed. Their software is integrated with numerous airspeed sensors + AoA sensors + gps location, speed, altitude info + terrain data. Even assuming Boeing's airspeed and AoA sensors all failed simultaneously, my basic iPad knows my GPS altitude, groundspeed, and local terrain proximity. Surely this same basic info is available to the Boeing flight systems automation! Why wouldn't the Boeing software use GPS data to stop CFIT as a last resort? Regarding pilot-software integration, I am inclined to worry that some pilot training programs might allow an over-reliance with staying on autopilot right into the ground, when VFR conditions allow hand-flying as an alternative before you hit the ground. Disclaimer: I am a mere recreational pilot with no experience of modern airliners, or their training regimes. I do have a Dynon Skyview that drives my autopilot, and it provides exceptionally good situational awareness. The data available to me is most certainly available to Boeing systems. Surely that should ensure automation failure safety? 1
facthunter Posted March 12, 2019 Posted March 12, 2019 I've never heard of any instruction requiring you to remain on autopilot in emergencies. It's assumed you do on an Autoland as you get the capability to land in zero vis (using more than one autopilot) as a requirement for added safety. The pilots monitor the progress of the autoland at all times. An "Autoland " is a "normal" operation. You don't need VFR conditions to exist to fly a jet liner legally manually if the required instrument s are functioning. . . Alpha Floor and this pitch down function are only supposed to operate in a critical situation to get out of that situation the plane has (inadvertently?) gotten into, not fly it all the way down.. ALL these warnings and actions (stick shaker etc) are relying on sensors. which are not infallible. Erroneous action can make a safe situation dangerous. Nev 1
dsam Posted March 13, 2019 Posted March 13, 2019 Nev, I wasn't quite suggesting pilots were "instructed" by training (or otherwise) to remain on autopilot, just that they habitually grow over-reliant on autopilot. If crew attention is diverted towards "systems rectification" rather than looking out the cockpit window at the ground rapidly approaching, that's a problem! I am aware that hand-flying is often done in IFR conditions, but if the primary flight instruments were showing senseless & conflicting data, a pilot might not want to disengage their autopilot in haste. That is where a GPS derived "terrain floor" in the autopilot should come to the rescue. I believe VFR conditions were in existence during this latest crash, thus the pilots could have had every reason to disengage autopilot (assuming they could & perhaps they did). Of course I accept that the actual cause of this crash may have nothing to do with the earlier Boeing crash - my comments are mainly meant to focus on cockpit automation parameters, and the way today's pilots interact with it all.
onetrack Posted March 13, 2019 Posted March 13, 2019 The terrifying, and overwhelmingly problematic fact remains, that two virtually brand new 737 MAX's, with experienced pilots at the controls, have flown straight into terra firma/ocean in recent months, and this is a situation for grave concern - for all concerned. It simply means that technology must be overwhelming the pilots, and that there are automation conflicts that were never envisaged, or thought through, simply because of the vast number of possibilities, multiplied by the number of components in the systems. Sensor errors are common, and every failure in the chain should mean the systems automatically revert to a simpler, fail-proof system, for backup. It appears the automation designers are designing electronic systems that are falling back upon reliance on other electronic and electrical backup, thus compounding information errors. 2
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now