737-Max 8 safety concerns
#31
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Come on, people. Any pilot can refuse to fly an aircraft if he or she deems it unairworthy. It's their signature and career PLUS all the passengers' lives on the line. Do you really think all and every North American MAX pilot today are being >forced< to fly their planes? That is an insult to our pilots. Don't you think maybe that all aircraft flight logs, especially for MAX aircraft, have been reviewed very, very carefully esp since Lion Air for issues related to AOA or airspeed conflicts? On another note: what pressures might exist in some carriers (or government policies) to overlook airworthiness concerns. Look at all the past maintenance-fault incidents for Ethiopian Air (avherald.com). Lion Air: noted instrument conflicts on repeated past flights for >that one, particular aircraft<, each 'fixed' yet problems unresolved. Do we have any North American carrier with MAX aircraft which have either exhibited these issues or, more critically, allowed said aircraft to continue to fly if unsolvable?
Last edited by ian_btv; Mar 12, 2019 at 10:16 am
#32
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When they do their testing of this (and make an already safe plane safer), can we put the entire board of Boeing on the plane, the engineers, plus a few select from the FAA, until at least 1000 hours has been done with a test pilot and a real pilot? No? Thought not.
#33
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The MAX 8 is statistically more dangerous than the 737 NG's and the A320 family.
As for your second paragraph, that is completely false. The 737-900 was already pushing the design limits of the 737.
The MAX's (hence my Frankenstein comment) take it a step further, with many aerodynamic drawbacks that Boeing has attempted to correct with software crap that obviously isn't working. That's not even talking about the mess that is the 737-10.
I love the 737 line, but it should've ended when they introduced the NG's.
As for your second paragraph, that is completely false. The 737-900 was already pushing the design limits of the 737.
The MAX's (hence my Frankenstein comment) take it a step further, with many aerodynamic drawbacks that Boeing has attempted to correct with software crap that obviously isn't working. That's not even talking about the mess that is the 737-10.
I love the 737 line, but it should've ended when they introduced the NG's.
What statistical analysis did you do in support of your first statement?
#34
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Good point about the flaps. The weather was quite hot that morning, and the airport is over 7000 msl. The density altitude might have been quite high. I wonder if they pulled the flaps at around 8200 ft and stalled. Then recovered, climbed too steeply (mountains?) and stalled again. Pure speculation, I admit.
The Lion Air report isn't final but a good amount of information has been released. Judging by the currently released information, there was nothing wrong with the MCAS system on the accident airplane. The failure was in an AoA vane/sender which fed the MCAS, and other systems, bad data.
Very little data out on the Ethiopian accident. The flightstats data, which is questionable due to poor coverage in the area, indicates that the flight never reached an altitude where the flaps would normally be retracted and the problem started almost immediately. MCAS is suppressed with the flaps extended. If that holds then this wasn't an MCAS event. The rapid changes in vertical speed almost immediately after liftoff, if correct, might indicate them trying to chase a bad airspeed indication (there are three separate IAS displays) either flying manually or on autoflight. If the airspeed displays differ by more than 4 knots you get "IAS DISAGREE" messages. Normal minimum autopilot engagement altitude is 800'.
We need a lot more information before we can say for sure what happened. So far, no evidence to suggest a connection between the two accidents.
#35
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So it seems China was right all along
Safety > Money
Safety > Money
#36
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Sounds conspiratorial to me. Minus the Boeing board, and multiplying several times the '1000 hours' flown before certification is approved, I think this has already been done. Show me the individual flight logs for these two lost aircraft. Show me the flight logs of all MAX aircraft in operation. Show me similar reports of AOA or airspeed conflicts in any other operating MAX aircraft. Any reports? Any at all?
Last edited by ian_btv; Mar 12, 2019 at 12:57 pm
#37
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I guess you don't follow international news? Tariffs levied against China. China has its own emerging aircraft industry. Are you sure >public safety< is their motive? Feel free to go breathe the air in Shanghai for several months and let me know how you feel. Oh, but that's just speculation ... collecting data and connecting the dots is wrong ... sorry.
#38
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https://www.reuters.com/article/us-b...-idUSKBN1OE06C
China's own airline industry is still about 15-20 years behind Airbus/Boeing at the moment, and for the next generation won't yet be of any direct competition. Your assumption is complete nonsense and, if all, shows YOU don't follow international news..
#39
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The geometric changes to the fuselage were limited to tail cone reshaping and some modification near the stabilizers that remove the need for the vortex generators on previous models while improving fuel burn through better aerodynamics. The engines (larger) were located on new pylons that, in addition to providing the necessary ground clearance, provide better aerodynamic positioning relative to the wing. The primary notable software changes relate to spoiler operation that reduces weight and improves flow and stopping distances on roll-out.
These drawbacks somehow add up to a 21k increase in MTOW and a range increase of 800nm at slightly higher cruise speed.
I'm genuinely curious as to the aerodynamic drawbacks you reference. As for statistics, they can be tailored to any point desired. We could look to the a320 and note a window in time at which 33% of the in-service fleet had crashed (AF296 at Habsheim). That was not an indicator of the airworthiness of the a320, and it is highly speculative to make similar deductions regarding the MAX at this time.
These drawbacks somehow add up to a 21k increase in MTOW and a range increase of 800nm at slightly higher cruise speed.
I'm genuinely curious as to the aerodynamic drawbacks you reference. As for statistics, they can be tailored to any point desired. We could look to the a320 and note a window in time at which 33% of the in-service fleet had crashed (AF296 at Habsheim). That was not an indicator of the airworthiness of the a320, and it is highly speculative to make similar deductions regarding the MAX at this time.
#40
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Awww ... you got me! and look at my bio: I've been doing so 6 years longer here than you have. Cheers!
Last edited by ian_btv; Mar 12, 2019 at 12:45 pm
#41
Join Date: Apr 2011
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Don't buy into China's aviation regulating body grounding the MAX purely out of concern for passengers. There are clear industry motives at work when the smoke is still rising from an accident scene and such conclusions are drawn with zero backup data. The slew of groundings are government officials running scared in the face of media drawing conclusions for hits.
#42
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Whether Apple, Caterpillar, Boeing/NASA ... or any lucrative technology sourced in the US ... you send the proprietary info over there, and they will copy it in short order ... you teach their scientists, and they will learn how to create and/or improve it themselves (the difference: no hiding the goal of profit at the expense of social or environmental improvement or advancement). It is happening now. By the time they are 'of any direct competition', there won't be any competition left to have. @YuropFlyer ... troll indeed! I think there's a reason why you sound so complacent ...
#43
Join Date: Jun 2016
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Don't buy into China's aviation regulating body grounding the MAX purely out of concern for passengers. There are clear industry motives at work when the smoke is still rising from an accident scene and such conclusions are drawn with zero backup data. The slew of groundings are government officials running scared in the face of media drawing conclusions for hits.
#44
Join Date: May 2013
Posts: 916
Any idea how long it will take for an investigation to take place so they are allowed to fly again ?
weeks ? Months ? Year ?
Seems like a big task .
weeks ? Months ? Year ?
Seems like a big task .
#45
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So we have the United States and Canada left. Boeing stock took another hit today.