Lion Air 737 Max 8 fatal crash

originally posted by: sy.gunson

originally posted by: Zaphod58

Soerjanto Tjahjono, the head of the safety agency, said during a Wednesday briefing that it was not clear if there was a systemic problem with this type of aircraft.

“We cannot yet say that there is a design flaw with the plane,” he said, adding that the Max 8 appeared to have developed a problem with the angle of attack sensor only after technicians had changed it the day before the doomed flight.

www.nytimes.com...

You're a real sucker for officials must be right syndrome

Man, I love me a conspiracy theory, but it has to make sense. You've already demonstrated to me that you don't know what you're talking about when you talked about spoilers being deployed because of a faulty airspeed sensor.

Probably an ignorant question,

Why are pilots seemingly not going back to basic analog instrumentation to fly the aircraft when the computerized controls are screwing up?

Seems to be fair number of accidents with sensor input data leading computerized flight control systems to do wrong thing and/or pilots to respond incorrectly to flight characteristics of the airplane.

They still install good ole analog artificial horizon, altimeter, turn/bank indicator and airspeed indicator - don't they?

One of the first I remember was AA crash in Columbia due to input of nav way-point when past that way-point and stupid computer did just as it was told and turned aircraft into mountains.

Seems way to much trust in electronics when seems to me whats really relied upon is software programmer had a good day or not.

a reply to: Phoenix

You answered your own question. Over reliance on technology, failure to completely understand all of that technology, lack of CRM....

a reply to: Phoenix

One reason Phoenix is that

#1 Pilots and Airlines were kept in the dark about existence of the MCAS system

#2 Without training in that MCAS system & handling etc, pilots may not have correctly identified the problem

#3 The problem occured because one system Digital Flight Data Acquisition Unit (DFDAU) gave erroneous data causing the autopilot to disconnect during the climb. That actually did revert Lion Air JT610 to manual control, but in fact the problem is that MCAS actually interferes with manual flight control



Zapod58 failed to add that Boeing failed to publish the existence of this technology in B737MAX Flight Crew Operating Manuals (FCOM) and Maintenance Manuals. Airlines had no idea about this system and Boeing kept it secret.

Nobody in the industry had any way to understand MCAS because it was Boeing's best kept secret. So secret they did not even demonstrate it to FAA for certification, so in fact we have a de facto uncertified aircraft in airline service and FAA take no responsibility for this massive breech of trust by Boeing

a reply to: RadioRobert

You seem to suffer reading comprehension difficulty. I previously cited that there was no fault in the Pitot system, but that there was in the DFDAU airspeed signals

originally posted by: sy.gunson
a reply to: RadioRobert

You seem to suffer reading comprehension difficulty. I previously cited that there was no fault in the Pitot system, but that there was in the DFDAU airspeed signals

spoliers on the wing raised, dumping lift in response to faulty airspeed indication

originally posted by: RadioRobert

originally posted by: sy.gunson
a reply to: RadioRobert

You seem to suffer reading comprehension difficulty. I previously cited that there was no fault in the Pitot system, but that there was in the DFDAU airspeed signals

spoliers on the wing raised, dumping lift in response to faulty airspeed indication

Clearly you did not read the word Indication?

DFDAU on the 737MAX provides airspeed signals to pilot displays and the FMC. I am saying the DFDAU provided faulty airspeed indications and this disengaged the Autopilot during climb.

If you want to learn more technical details about the B737 I suggest you join forums for aviation professionals like this one:

sjap Maintenance Experience Exchange

a reply to: sy.gunson

Still an over reliance on computer/automated systems and seems there was a lack of reference to basic flight instrumentation that's been around forever and ALL pilots should be proficient at using when "wipe yer ass" systems go haywire.

So bad airspeed reading kicks out autopilot climb, pilots ignore bogus airspeed or don't have comparative instrument to verify, mcas does stall prevention as programmed due bogus airspeed, pilots resume auto climb and set systems up for repeat performance. Button pushers sometime fail spectacularly.

What your post complains of is a crew deprived of a "system management function" and that's what I see "systems managers" rather than pilots. Mine is saying turn the crap off and "pilot" the airplane on analog instruments till electronics can be sorted out.

So tell me when's last time analog A/C such as 737 (early models) 727, 747, 707 or similar ever had issues such as this.

How many wonky airbus incidents for that matter, plenty from what I understand.

a reply to: Phoenix

There have been several incidents with both Boeing and Airbus aircraft in recent years. Even with bad data they should still be able to fly the airplane. There were a number of Airbus aircraft that had bad data because of bad pitot tubes installed, and they landed safely. There was a 737 crash in Russia caused by the crew failing to activate pitot heat, where they didn't fly the aircraft and stalled it.

It could happen on older aircraft as well as newer aircraft, but the industry is definitely taking notice of the over reliance on technology.

a reply to: Zaphod58

Thanks Zaphod58,

I have just few flight hours under my belt and continually scratch my head when hearing of flyable aircraft being crashed.

Seems much "auto" systems in passenger world are to make last slim dime for shareholder's anyway.

Is it worth lives?

AF 447 is a good example of a short period of questionable data then back to good data and the pilot still held it in a deep stall all the way to the ground.

Not a good way to run an airline.
Spend the minimum Lion Air

Very interesting questions being raised.

originally posted by: Zaphod58
A lot of confusion and anger over the MCAS now. One pilot said he's flown the Max "a couple times a month for almost a year" and had no idea it existed. He wants to know what else Boeing didn't tell them about. Another said his transition from NG to the Max consisted of an hour or so with an iPad.

Seattle Times

Yikes
Some of the comments on that page are pretty revealing about Boeing Corporate Policy.

In the early days there was a corporate policy that required bringing concerns forward and insured review and protection of those who spoke up. By 2005 it was obvious that you would loose your career if you did speak up.

originally posted by: Zaphod58
Very interesting questions being raised.

I would think they would have one toggle switch to kill AP, auto trim and any other automated feature and only fly off the analog instruments when things go haywire.

It’s reasonable to ask why the pilots didn’t shut off the trim system during the roughly 10 minutes they were assessing the plane’s behavior, he said. A decades-old emergency procedure teaches pilots to flip two switches to cut power to the motor that was pushing the nose down.

I do not see how we could ever safely have automated driving when you have a heck of a lot more manufacturers, makes and models to mess things up vs just Boeing and Airbus.

The preliminary report goes into detail about the previous flight, as well as the accident flight. On the previous flight, the Captain's stick shaker activated during rotation on takeoff, and remained active during the entire flight. Passing 400 feet, the Captain noticed an IAS DISAGREE warning on the left PFD. He passed control to the SIC, and assessed the issue. He determined that the left hand PFD had the issue. He also noticed that the aircraft was trimming nose down, so moved the STAB TRIM switches to CUT OFF, at which point the nose down trim stopped. The flight continued under the command of the SIC and landed safely at Jakarta. Prior to the flight, the Captain had been informed by an engineer that the AoA sensor had been replaced, due to previous airspeed issues.

After the flight landed, engineers performed a flushing of the pitot and static ADM, as well as cleaning the connectors of the elevator feel computer, to rectify the FEEL DIFF PRESS warning. The engineers signed the aircraft off as being ready to fly after performing ground tests. The aircraft departed as JT610 later that night.

Once again the stick shaker activated on rotation, and the DFDR recorded a 20 degree difference between right and left AoA readings. The SIC asked ATC for altitude and airspeed readings, and reported flight control problems. Upon retracting the flaps, the aircraft began automatic nose down trim, which the pilots counteracted by inputting nose up trim. The flaps were extended to 5 degrees, and the AND stopped. Upon retracting back to 0, the AND began again and the crew fought it until the end of the recording.

reports.aviation-safety.net...

It's turning into a mess. Boeing raised questions about Lion Air maintenance and training procedures, and now Lion Air is threatening to cancel delivery of future aircraft.

a reply to: Zaphod58
Something tells me the truth is a combination of column A and column B. There were certainly other operators who said they were unaware of the changes Boeing introduced. And Lion Air's record speaks for itself.

S##t like this is exactly why manufacturers and operators were regulated in the first place, and why the dumbing down of maintenance and pilot training world wide over the last 20+ years was a bad idea. All so people could travel to destinations at ridiculously low prices that dont reflect true costs. Something has to change soon.

a reply to: thebozeian

Almost certainly. They might have been removed from the blacklist, but they certainly did something to get there in the first place. And sorry but I don't see them changing THAT much. There are still too many stories about them out there.

Boeing didn't do themselves any favors by screwing up and not telling operators about MCAS. I can't say that I'm surprised they didn't though if I'm being honest.