737 MAX CRASH

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Garys72Duster

Garys72Duster

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What do you guys think about two brand new 737 Max airplanes going down in the past 6 months? System failure? Pilot error ? Or a combination of the 2.
 
They crank out 52 in a month! That's all I see in the air over here under John Wayne flight path, and a few 757 cargo's. Popular aircraft for sure.
 
There was a problem with the first model 737 aircraft in the 90s to early 2000s where a hydraulic control valve assembly malfunction in tail of the aircraft would cause the elevator and rudder to act oppositely of the pilots input. Several of those inverted mid flight and barrel rolled into the ground before the NTSB and Boeing solved the issue. The facts are stating that there are fundamental problems in the original design of the aircraft.
 
Looks as if the anti stall system is kicking in, and causing the nose to lower via computer inputs to the control system. The pilots fight back by pulling back on the yoke, but the computer wins and flies the airplane into the ground, killing all on board. Wow! Or into the Java sea, as in the Lions air disaster a few months ago. Same plane, brand new, only a few months old. Stay off the MAX 8 until they get this figured out.
 
If the angle of attack sensor is not right all kinds of things can happen.
Looks like a little wing thing on the side of the plane and moves up and down depending on the air stream in relation to the plane's angle.
I've never worked on that plane and have been out of it for years now.
But there should be two.
One on each side for redundancy.
What systems they feed, IDK.
Probably captains on the left and FO's on the right.

Update: Boeing Issues Warning About 737 Max Jet in Response to Lion Air Crash
 
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Lack of training on the flight crew could be an issue on such a new aircraft. I worked on 737's for 12 years. Started on the 737-200 classics and yes they had several service bulletins on yhe rudder. 737-400's had an improved rudder pcu and more advanced flight management computer. 737-NG and ETOPS certified aircraft had even more advances in the PCU design as well as the flight management system. The angle of attack and the pitot/static all have to be operating in sync obviously, but there is still manual cutoff switches on the throttles and the glareshield to kill autopilot and give full control back to the pilots. As a 737 guy who also had a lot of experience on the Mad Dogs (MD80-MD90's) this is very concerning to me and the industry of my fellow airmen
 
I haven’t worked on the 737 Max, but have other commercial acft that were fly by wire. These had a stall avoidance system that would automatically nose the acft over given certain data inputs from sensors etc. When we tested them, the controls in the cockpit don’t even move so there’s no direct feed back to the flight crew, it’s not like the old acft with cable systems where you could fight against the system for manual control. These acft used a 4 pitot system with no stall warning vane, the difference in airflow over the pitot tubes lets the system know the acft attitude. It may very well be a software glitch, time will tell. The isssue comes in with low altitude say 250-300 mph and all of a sudden the flight management system commands a nose over. Unfortunately there’s not enough altitude or time to sort things out. As I said I’m not familiar with the 737 but this is what I’ve seen on others. Hopefully they get it sorted before more happens. It would not be the first time a manufacturer has had trouble out of pitot tubes. One that is not reading correctly can affect the whole system ice, rain so on can create issues. That’s how the Air Force lost one of the B2’s. Moisture in the pitot static system from sitting in a humid environment. Feel sorry for the families when things like this happen.
 
Software issue, surprises and challenges pilots. I fly in them all the time - domestically.
 
Pito tube on the nose? Boeing stock took a dump today. Rate on this aircraft is 57 per month starting in June, going to 63 next june.
 
I used to love flying when my dad had his Piper but I hate flying commercial airlines anymore. I'll drive whenever I can.
 
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This idea of a pilot having to outthink a computer is fairly troubling. I'm not sure technology is actually improving anything, here
 
Way too early to tell if there is a systemic problem with the plane or not. Either way, I’m willing to bet that the US pilots are better trained to deal with the issues that might have occurred than the ones that were in the pilot seats of the 2 that crashed.
 
Curious to see how fast Boeing reacts and what the
Ddaddy said:
Way too early to tell if there is a systemic problem with the plane or not. Either way, I’m willing to bet that the US pilots are better trained to deal with the issues that might have occurred than the ones that were in the pilot seats of the 2 that crashed.
Click to expand...
yes. The interview today from a SW piolet said there is an override switch and could have been avoided. There is an apparent system issue that will be corrected sometime in April. Until then, it will be interesting to see if the FAA steps in and if Boeing continues to deliver aircraft from Renton. Sad either way.
 
The 737 Max 8 has literally hundreds of thousands of safe flights already. But with 32 years with MD and Boeing I'm probably to close to the situation to comment objectively. It's to soon. Let's let the process work. I will say I know my coworkers at commercial aircraft care, and I think they build world class aircraft. My heart goes out to them and the crash victims and their families.
 
Went on a family vacation and flew to Florida, first time ever on a plane, granted the trip down was uneventful, coming back though a few storms was another thing, probably about 20 times I watched my soda raise up and fall back into my glass while my hand was stationary from the turbulence, then later about 6 times the plane felt like it was rapidly dropping, I literally felt weightless in my seat then and a abrupt thud with a sound like metal being dropped to the floor, now I'm wearing my drink! Scared the hell out of me. When we landed were getting thanked by the stewardess for flying on our way out of the plane, I walked by her saying a very stern "NEVER AGAIN".

I was 15 at the time, and true to my words, I have NEVER boarded another plane since that trip, I prefer to fly low.
 
I have flown a lot for business, over 250 flights and about 380,000 air miles travelled. I did over 104 flights in one year alone.

I have experienced severe turbulence, lightning strikes, system failures and even a twisted aircraft that couldn’t close the main door so departure was aborted.

All in all, flying is still incredibly safe and American pilots are the best in the World.

These events with this aircraft does not change my opinion.
 
I used to do flight control software for missiles (a really long time ago, and we didn't have to fly for very long ;-)), so I know a little bit about this stuff - here's what I've read about these incidents (the latest crash is still under investigation, so pretty much everything about this one is speculation)

Boeing added MCAS to correct a loss of lift condition, and speculation is that this 'fix' that probably shouldn't happen during take off.
https://phys.org/news/2019-03-ethiopian-airlines-mcas-boeing-max.html

Boeing is releasing an updated autopilot shortly - Boeing plans autopilot software update after two 737 MAX crashes | ZDNet
That article includes this bit

From the Boeing press release:

A pitch augmentation control law (MCAS) was implemented on the 737 MAX to improve aircraft handling characteristics and decrease pitch-up tendency at elevated angles of attack. It was put through flight testing as part of the certification process prior to the airplane entering service. MCAS does not control the airplane in normal flight; it improves the behavior of the airplane in a non-normal part of the operating envelope.

Boeing's 737 MAX Flight Crew Operations Manual (FCOM) already outlines an existing procedure to safely handle the unlikely event of erroneous data coming from an angle of attack (AOA) sensor. The pilot will always be able to override the flight control law using electric trim or manual trim. In addition, it can be controlled through the use of the existing runaway stabilizer procedure as reinforced in the Operations Manual Bulletin (OMB) issued on Nov. 6, 2018.​

There are 3 ways to disable this, per an article I found this morning (and can't find again).
This isn't the same article (the one from this morning showed the locations of the trim control (yoke - left thumb, IIRC) a pitch wheel/crank, and a circuit break, IIRC)
Satcom Guru: 737 MCAS - Failure is an Option

The earlier crash led to Boeing letting pilots know about the MCAS (from Answers to Your Questions About the Boeing 737 Max 8)

Are all pilots that fly the 737 Max 8 explicitly trained on Boeing’s MCAS flight control system? Do they learn how it works and how to turn it off if it malfunctions?

— Alexandra Zaporozec, Chicago

Before the crash of Lion Air Flight 610 in October, Boeing had not notified pilots that the MCAS was operating on the Max or that in certain circumstances it might cause the airplane to pitch down. After the Lion Air crash, Boeing sent a service bulletin to its customers, and the Federal Aviation Administration followed up with an emergency directive ordering Boeing to change the airplane flight manual and provide the flight crew with a way to avoid being surprised or reacting incorrectly to the MCAS.​



I remember flying one of the newer/bigger models (737-800 maybe?) on an early morning flight to Southwest. The landing approach was odd and disturbing (the guy I was with worked on the 737 software a while back, and he gripped the arm rests a couple of times). We said something on the way out and found out that was apparently the second or third commercial flight with that particular airframe, and the first time for that crew, and it behaved a bit different than the -700. They Max8 has more 'bit different' handling, and they added software to protect against one condition, but it may be that they have found a situation where the 'fix' is a really not good thing (esp. if this last crash is the same root cause as the previous).
 
Ddaddy said:
I have flown a lot for business, over 250 flights and about 380,000 air miles travelled. I did over 104 flights in one year alone.

I have experienced severe turbulence, lightning strikes, system failures and even a twisted aircraft that couldn’t close the main door so departure was aborted.

All in all, flying is still incredibly safe and American pilots are the best in the World.

These events with this aircraft does not change my opinion.
Click to expand...

Yup, the statistics don't lie. No doubt, it is the safest form of transportation, but when crashes occur that kill a couple hundred people in one shot, it makes it seem not so safe. My way to put it into perspective is this......imagine having the same number of plane crashes a year as automobile crashes. Then that really makes you understand how safe flying really is.

And here I am saying that having never flown and WILL NEVER FLY. I am one of those who says if God had wanted mt to fly, he'd have given me wings. It's just not something I ever want to do.
 
I haven't flown a ton, maybe 22 or so, but I've had some rough ones, a close call at altitude as well. I would still fly no problem, if I were a "gichy" person however, I might not. On a Max8, maybe not at present 'til this gets figured out.
 
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