A Huge Safety Issue Concerning the 737 MAX Series


#21

Im indonesian and i never heard of it :)


#22

Lol, I would probably only know one word in the whole article, Hati-Hati. I’m pretty sure terima kasih or permisi wouldn’t be in the article. After living in Indonesia for 2 years that’s basically all the Indonesian I know. 😂

Sorry, a bit off topic but I just had to say that


#23

I’m pretty sure the autopilot could not put the plane into a dive as the 737 max is mainly not fly by wire.


#24

I was replying to Indoaviations comment


#25

So after the autopilot sent the plane into a dive couldnt the pilots disconnect AP and pull up to get out of the dive? Correct me if I’m wrong.


#26

Good question genius but it’s fully confirmed that it wasn’t human matinence error?


#27

It can Matthew. A computer is only as good as what it’s told. For instance-if the autopilot has the wrong AOA information-if the AOA vane (or pitot tubes) are stuck or have an issue the autopilot may think that the plane is nose up and about to stall (or at a dangerously low speed-a-la AF447) in this case-it doesn’t matter if it’s fly by wire or conventional-the safety features like a stick pusher will engage and cause a dive.


#28

There’s something I don’t get.
Maybe I’ve missed something.

There’s this:

Boeing would like to call attention to an AOA failure condition that can occur during manual flight only.

And there’s this:

"Additionally, pilots are reminded that an erroneous AOA can cause some or all of the following indications and effects:

- Continuous or intermittent stick shaker on the affected side only.
- Minimum speed bar (red and black) on the affected side only.
- Increasing nose down control forces.
- Inability to engage autopilot.
- Automatic disengagement of autopilot.
- IAS DISAGREE alert.
- ALT DISAGREE alert.
- AOA DISAGREE alert (if the AOA indicator option is installed)
- FEEL DIFF PRESS light."

So, there’s a change that erroneous AOA data can cause the aircraft to go into an uncommanded nosedive during manual flight only. In that case being on autopilot seems safe.
BUT, when erroneous AOA data can also cause automatic autopilot disengagement, than the aircraft will go into a nosedive as well.

To me this sounds like a loop, which seems impossible to escape.

Am I missing something?


#30

You need to disengage the electronic stab trim once in manual flight to stop automatic stab trim adjustments. Once you have done that you won’t have any further possibility of erroneous automatic stab trim changes.


#31

i fear with these maintenance checks and NTSB report this might be like the 787 and Qantas 32 situations


#34

Don’t you guys think that the plane suffered some failures before it crashed? maybe it suffered engine failure. well what do you think about the 737 MAX. Had anyone flown in one before?


#35

Maybe it was a stall too, we don’t know. It’s so early in the investigation.


#36

An aircraft that stalls at 5000 feet won’t hit the ground at 600 mph.


#37

Where did you see that it hit the ground at 600mph? When it impacted it was dropped like a dead weight.


#38

My question is, is this a serious enough issue that this is possibility serious enough to ground all max aircraft?


#39

It was 400mph. My bad. From the data collected by flightradar24 and others.


#40

I would think not. Logs have showed that there have been issues with this specific aircraft with similar problems to the one reported. This aircraft should have been closely inspected after the first incident. That could have helped prevent this if an issue was found.


#41

So you take the article I posted on the Lion Air thread this should be on, and post it here? How nice.


#42

Are you talking about this main post? This thread was created 24 hours ago, way before your reply on the Lion Air thread. Thank you for that information on that thread though!


#43

its been a bit confusing, for me anyway, with some contradicting/conflicting reporting or info coming from Indonesia.from what im gathering as of late, it seems like they’re saying the last 4 flights showed erratic airspeed data, but the last 2 showed AND erroneous angle of attack on top of IAS. after the 3rd to last flight (which went to bali) , maintnence worked on it for the 2nd straight time, but added replacement of the AOA sensors … after this “fix” is when the “roller coaster” flight the passengers have complained about from bali to jakarta happened. this flight not ONLY experienced the crazy airspeed data w/ loses of altitude and nose down dips as the previous 2 flights, but now on top of that, first reported the new angle of attack erroneous data. what a coinkidink eh?? so the “fix” or repair done of replacing the AOA sensor not only didnt fix the airspeed issues, but now added a new problem on top of existing ones of unreliable airspeed readings, with now whacky AOA readings. the flight crew on flight 41 from bali to jakarta, obviously reacted appropriately enough to continue on to jakarta w/out returning back to Bali. its only natural to ask, what was so different this crew couldnt?? its gonna be interesting to see exactly what repairs or work was done, and when. if they replaced the aoa sensors in bali, then what did they do after they still experienced problems & now a new one, once in jakarta? it blows my mind w/ 4 straight flights of reported erratic/erroneous airspeed data (specifically the capt side readings bein erroneous, while FO side correct) , the last one added the AOA to the list and such loses of altitude/nose down attitudes, HOW was this plane deemed air worthy by lion air/maintenence?!? its a shame. all boeings directive is really saying is NTSC/Indonesia has told us this is the info theyre seeing-so based on what THEYRE saying, were gonna recommend to follow our already established procedures, which youve all been trained to do lol 🤔🤔 it might as well read, “ok guys! brush up on what youve already been trained on, of how to react or recover to this possible erroneous data/air speed /AOA data”, right?! just feels kinda like an air france 447 situation, of whats the true cause/which to "blame ". is it the pitot tubes freezing/erroneous data versus the incorrect actions by the pilots in responding to the erroneous data… in this case, prob boeing saying pilots incorrect action to the data and/OR maintnence not repairing properly/not grounding the plane versus lion air saying its boeings fault for the incorrect data of the plane. i know the MAXs are much more computer oriented/automated. we found out w/ qantas 74, the similar issues w/ airbus how the protections meant by those computers can do the exact opposite & cause a problem. i dont know how the maxs “protections” work, when the AP will disconnect in receiving these crazy airspeed or AOA readings. from the sounds of it, this crew woulda been dealing with the plane continually being put in a nose down attitude with the system trying to counteract the inaccurate high nose AOA. im sure the findings will show they had alot of conflicting data, warnings, and in a confusing situation battled control along w/ the conflicting info. ill never forget hearing aeroperu 603 Cvr-hearing all these alarms blaring, on top of those warnings or readings making no sense… overspeed warnings & stall warnings at the same time, that are in total conflict of possibility or reality? its pure chaos & easy to understand getting overwhelmed. lastly, its also not very reassuring this is the same country/safety committee of NTSC who have stuck by/official report saying silk air flt 185 was undetermined bc it couldnt rule out a rudder malfunction or other tech failure *eye roll * the NTSB (along with boeing) showed very clear & convincing evidence that was a deliberate act by the pilot/captain. another example is egypt air 804 w/ egypt saying it was a bomb, when a cvr clearly shows pilots saying “fire”, wreckage shows a fire & the BEA go out of their way to try to state this all points to a fire not a bomb. also that theyve seen zero evidence of explosives residue found, as the Egyptians have claimed. my rambling point is,some governments or investigation bodies abroad in certain countries, tend to put their own best interests over facts & truth, sadly. hope jt 610 isnt one of these! (p. p. s… sooo sry for my novel here! its my first comment&visit to this site! plz dont crucify me lol)