{I}n reality there are about a dozen dimensions for why these accidents have occurred. Everything from larger engines being fitted to old planes, to corporate culture at airlines and aircraft manufacturers, to lack of proper training for flight crews transitioning to this aircraft, to cover ups and fraud.

That is not correct. I explained this in detail yesterday in post number 2785.

https://www.flyertalk.com/forum/31847099-post2785.html

I have zero idea where these figures came from. The c-series cost $6.1B to develop. A new narrow body by Boeing would cost more (as it would be designed for a broader range of sizes, probably three), but some of the technology already exists. Usual estimates are $10-15B max. Boeing has now spent more than $15B for the MAX so far.

The 797 is a concept that got wiped out by the a321neoLR and XLR. Had Boeing launched it earlier, perhaps a market of 1000-2000 planes, but the bottom half of that market has gone away with the a321neo. see https://www.economist.com/gulliver/2...pose-to-boeing (paywall). The remaining demand can be filled with 787 or 333s.

And I might add the MAX was NOT designed to be a permanent offering. The original plans were for Boeing to launch its' Y1 project (100-250 seat) project in 2020. That was put off by the MAX till 2030. But the big market (over 50% of Boeing's sales) is the narrow-body market.

No. TheA320 is a 1980s design (vs a 1960s design for the 737). Because it (a) sits higher, (b) has much more modern architecture and systems, and (c) is only at a single stretch with the A321 (vs. 4 with the MAX10) it was easy to update the engines. Airbus had the luxury of re-engining the plane relatively easily, and more importantly, was able to stretch the design to a much longer range with the A321neoXLR. Boeing was not able to do either of these things.

Had Boeing gone with a new narrowbody in 2011, Airbus might have elected to stick with the A320 series for another ten year, then build a new plane. Boeing was forced into it's choice by Airbus and then delaying making a decision.

I am sure that if you polled Boeing executives and workers today, 99.9% would say they wished Boeing would have launched a new narrow body in 2011 as originally planned.



+1. Too much plane combined with too many heavy systems. The 757 burns more than 25% more fuel per seat than the A321neoLR does No way that new engines can fill that big of a gap.

If true, then the engines could have been mounted in the same position as in previous 737s. But they couldn't. Not enough clearance.

So the MAX's engine size, in an absolute sense, if looking only at the engines, is innocent. But no one flies an engine alone from Denver to San Francisco. The size of the MAX engine relative to the aircraft it was being mounted on started a cascade of consequences.

Forgive me for using layman's terms here. Regarding the MCAS required for certification, is that just a technical FAA requirement? In other words, is it one those regulatory requirements that has no bearing on the actual air worthiness of the aircraft in question, but just some kind of metric the FAA put in there? Put another way, in your view, if this certification weren't a requirement, is the Max air worthy for the run of mill proficient American trained pilot?

READ BEFORE POSTING

Once again many posters in this thread have forgotten the FT rules and resorted to "Personal attacks, insults, baiting and flaming " and other non-collegial, non-civil discourse. This is not allowed.

Posters appear to be talking at others, talking about others, not discussing the core issues. Repeating the same thing statements, saying the same thing LOUDER is not civil discourse. These problems are not one poster, they are not just one point of view, ...

As useful as some discussion here has been, continuing rules violations will lead to suspensions and thread closure. Please think about that before posting.

The purpose of FT is to be an informative forum that, in this case, enables the UA flyer to enhance their travel experience. There are other forums for different types of discussions. This thread was had wide latitude but that latitude is being abused.

Bottom line, if you can not stay within the FT rules and the forum's topic areas, please do not post.
And before posting, ask if you are bringing new contributing information to the discussion -- not just repeating previous points, then please do not post.

WineCountryUA
UA coModerator

Absolutely. I don�t think I�m Chuck Yeager or still working as a test pilot anymore but rather an average, conservative, line pilot with a family at home. Point is, I�m not going to put my life at risk if I don�t feel 100% comfortable in an airplane. That being said, I�d fly a MAX tomorrow if they�d allow it. We can grandstand all we want here, reality is both the B737 and A320 are fantastic, proven aircraft.

Not to re-hash 100+ pages upstream this thread but MCAS could always be shut off using established runaway trim procedures (which were NEVER fully performed on both accidents.) Everyone is riding Boeing (justifiable so IMO) but much of the responsibility lies on the operator and the training/experience level of those pilots. These failures are a common factor in both accidents that conveniently gets left out of the discussion.

Once the MAX gets back online the pilot awareness of trim issues will be at the forefront of one�s mind and the required training will only reinforce those established procedures.

Assuming MCAS triggers again post-grounding, which is a huge assumption considering the scrutiny on that aircraft. It�s 4 actions, two trim-disconnect buttons, located inches from the co-pilot�s left knee that will disable it. Whole procedure can be completed in less than 5 seconds.

Yeah I was referring to this exact post:


In other words, I thought (incorrectly), up until yesterday, that planes were allowed pitch up (regardless of the reason) and as long as pilots were trained to counteract this manually, the plane would be good to go. I thought that it was perfectly okay to have a plane that pitches up when thrust is applied and requires the pilots to push down on the nose. This apparently is not the case. Although I wonder if the rules are different for military and experimental aircraft, or do they apply to all aircraft regardless of type? In any case, I thought that the software's only purpose was to make the MAX behave like the NG, and did not realize that there were additional regulatory requirements that would not be met if not for its presence. I learn new stuff here all the time. Thank you for the information.

A good deal of the aviation terminology I know, I learned from FT and from various websites that I found after posts here got me curious about something. One of my favorite things to do on UA flights at least is to listen to Channel 9/From The Flight Deck, when it's available. Before I joined FT, listening to ATC would have been like listening to a different language, but now, I can understand most, but not all, of what's being said.

- Airbus designed the A320neo because the A320ceo’s range and economics on some routes lagged behind the NG, which had engines and wings that were a generation newer.
- Boeing wanted to try and maintain an advantage over Airbus. It’s customers didn’t want to pay more for a clean sheet airplane, so it went with the MAX.
- Boeing has been consistent in saying that it would have preferred a clean sheet narrow body, but the market had no interest. You don’t invest billions in a product your customer won’t buy.
- The C-Series/A220 is made of aluminum and destroyed Bombardier. It is a horrible example of a development program.
- There’s no feasible plan to economically make 50-70 carbon fiber airframes a year. It’s not clear there’s a benefit to have a carbon fiber narrow body.
- All modern airplanes have aerodynamic flaws that are corrected by software. If you don’t want to fly on an airplane with software, you need to stay home.
- As the public and airlines push for more fuel efficiency, there will be more substantial software corrections required.
- Engine placement on the MAX improved the COG and handling characteristics. Under certain extreme conditions, there’s too much lift and MCAS is intended to smooth out the handling. A good analogy is a car: you want linear increase in force as you steer and brake. If it got easier, it’d be difficult to respond.

A real explanation would have more facts and less competitor branding.
PS: I have flown on the 'MAX' several times and I will fly again without a worry on it when it returns to service.

The problem I have with this analysis is the treatment of the Boeing/Airbus rivalry and the "lack of interest" in a clean sheet narrowbody as somehow justifying what Boeing did. If it really was impossible to put out a new plane that avoided the design defect of the MAX, another option was to put out no new plane at all and cede that end of the market to Airbus.

The point is anything is better than putting too large an engine onto a 50 year old design and causing two crashes and hundreds of fatalities. So what if Boeing loses some market share or puts out a plane nobody buys? That pales in comparison to what Boeing actually did.

The situations in which MCAS would normally activate are not situations where the airplane is ever expected to be in normal operation. For that reason, I've never flown a transport jet in such a situation.

Title 14, Code of Federal Regulations, Part 25 governs the certification of transport aircraft. One of many requirements is that as Angle-of-Attack (AoA) increases, the control forces to maintain, and continue to increase, that AoA must increase proportionally.

https://www.law.cornell.edu/cfr/text/14/part-25

That is a requirement for all transport airplanes, and probably a requirement for all non-transport airplanes, too. They are certified under 14 CFR 23.


That is exactly how all airplanes with under-wing engines respond. When hand-flying, as I increase thrust I push, and trim, forward. As I decrease thrust I pull, and trim, aft. Aircraft with tail-mounted engines have virtually no pitch response to power changes. On those, the nose won't pitch up, or down, until the airspeed starts to increase, or decrease, as a result of the thrust change.

Quote:

do they apply to all aircraft regardless of type?

I addressed that above for certified civil aircraft. Military aircraft are not certified under 14 CFR 23 or 25. Pilots flying military aircraft are not certified under FAA rules. Experimental aircraft also have completely different rules with which I am not familiar other than they can't be used commercially for passenger or cargo transport.


That's not your fault. Many reporters, with little or no understanding of these technical issues, have continued to report exactly that. Unfortunately, many of their readers think they understand the issues related to the MAX from reading those inaccurate or misleading stories.

Exactly. This has nothing to do with Airbus vs. Boeing. It has to do with a collective failure of products in the narrowbody market and no real competition from any other manufacturer.

C-series is 46% carbon fiber https://www.materialstoday.com/compo...-with-cseries/

It is (along with a cutting edge wing with substantial carbon fiber parts) what gives the C-series better fuel burn. Part is it being a new optimized plane, part is the additional use of carbon fiber.

The 787 is 50% by weight composites, and the A350 is 53%. see https://en.wikipedia.org/wiki/Airbus_A350_XWB (under materials tab)

For contrast the 737 is 4-6% carbon fiber (depending on model) the MAX and A320ceo are 10-15%, the neo is slightly higher (can't find the figures I have seen earlier on it).

I find that hard to believe. The industry cares about fuel efficiency and a clean sheet design would have been even more fuel efficient. You're saying that if they could snap their fingers and make a clean sheet design tomorrow that blows the pants off the A320neo, nobody would buy it? I don't think so.

What is probably true is that traditionally all Boeing customers wanted a more fuel efficient narrowbody sooner than Boeing could create a clean sheet design. But at that point, Boeing should have just realized that there was no way they could do it safely and told them no. And wasn't the Y1 supposed to enter service in 2020 (as estimated in 2011) anyway? Would have been a hell of a lot better for PR if they could have done this without the crashes and deaths and groundings.