To be fair, hydraulic loss on the 737 is/was worse than the 320 has ever been.

BigPistonsForever,

Your post about hanging the engines out the front to keep the aircraft appeal is half true, it was the only way they keep the 737 competitive without resorting to a clean sheet design; airlines like the 737 and trusted that Boeing would produce a better 737.

IMO, wet fuselage fuel tank versus aerodynamically compromised airframe are not comparable.

This won't be decided by this thread or forum, it'll be the airlines and their customers. (And perhaps Boeing if they continue to aim at their feet instead of the sky)

I disagree. The A321XLR does not work without the conformal fuel tank because the number of conventional approved belly hold aux tanks required would mean there would not be enough belly hold space left. There is obvious pressure on the regulatory bodies to approve this mod.

Conformal fuselage fuel tanks by definition are not approved. To get around the regulatory requirements will require “special” approvals. This is the exact road that ended up with 2 crashed MAX jets. Yes Boeing is obviously trying to change the channel, but that does not change the fact that this is significant post MAX test for all regulators when dealing with grandfathering legacy aircraft design changes

I hope the lessons from the MAX have truly been learned.....

Could this be meant to become some sort of deal? The MAX will not need the tricky third sensor and the XLR can get it's tank?

Whatever we disagree on, learning lessons from the Max is something hopefully everyone agrees with.

No deals, it's either safe or it's not, NO compromises.

Big Pistons Forever

"Conformal fuselage fuel tanks by definition are not approved. To get around the regulatory requirements will require “special” approvals. This is the exact road that ended up with 2 crashed MAX jets."

Are you suggesting that Airbus are planning not to tell EASA the whole truth about what the conformal tank does, and how it does it?

DaveReidUK

I am not suggesting that EASA wasn’t being transparent about the conformal tank design. What I am suggesting is there is a lot riding on getting it approved, as the XLR variant is not viable without it. Since this tank does not meet the certification requirements, other means will be required to mitigate the risks.

Again my point is the PROCESS to evaluate those risks and ascertain what are appropriate mitigation strategies using a apolitical transparent process, is the test to see if the lessons from the MAX tragedy has been learned.

The abject failure by Boeing and the FAA in dealing with a legacy aircraft regulatory non compliance, the inability to meet stick force gradients in some flight configurations, is fundamentally that of a process that should have worked but did not.

Sunlight is the best disinfectant. If Airbus and EASA can go on the record and prove they have used a transparent and thorough process untainted by commercial pressures or regulatory capture, then they can blow off Boeing. If substantial structural changes are now determined to be required to get the tank approved, which IMO is going to be the case then, like it or not Boeing was right.

Boeing are becoming an embarrassment......the 321XLR is an excellent piece of kit and its timing is amazing. Boeing have nothing to offer...a 737 Max with no credibility and a 777x that is a white elephant. They are clueless at the highest level from what I hear from inside.

The A321XLR is great too

I've tried even serious reinterpretation, but none of the available icons quite fit a "shoot the messenger" quip.

In one of the several 737 MAX threads or Boeing-focused threads - or more than one of these - a good number of comments were made about how professional engineers have an obligation, as a matter of professional ethics, to call out safety concerns, design flaws, and other similar serious concerns. Even if it means putting career at risk - and of course these comments prompted others to note the realities of the working world.

Presumably Boeing's comments to EASA weren't the imaginings of some idle lawyer or SLF with a latent "aviation enthusiast" trait to expunge. Presumably the comments on the safety of the tank design, or its adherence and conformance to certification standards (I'm not sure which is the proper context here), were originated by an engineer whose professional obligations meant something to that person.

How does Boeing's awful recent failures and its longer-term decline obviate the obligation of an engineer who spotted this safety issue or certification concern? -- how does Boeing's bad repute at this time require the engineer to find someone else to deliver the comment? Double standards, it seems to this SLF/atty, are in play here.

Quite a statement for what is effectively a paper airplane at this point.

Bingo!
New rules and the like routinely go out for public comment - I used to see those on a semi-regular basis. There would be a focal that we'd direct any comments to that would incorporate those comments into an input to the relevant authority. It's call 'doing your job' and 'due diligence'.
"Wet fuselage" fuel tanks have not been previously used on commercial airliners. Perhaps there is a good reason for that...

Meh. It's a 321LR with a bit of extra range.

More than a paper A/C
 

It seems from what is written here https://www.airbus.com/newsroom/news...bly-phase.html, that the XLR is well beyond the paper phase.

So, you can pronounce an aircraft "an excellent piece of kit" more than a year before it's scheduled first flight, and "its timing is amazing" more than two years before it's scheduled to certify?
Based on that, the 787 is the greatest aircraft ever built...

WillowRun 6-3

In both cases there is a process by which concerns can be vetted. The vetting includes regulatory agencies or their designates. Presumably there was not enough validate concern with the B737 to overturn the certification of the Max.
Yet there is a concern for the possible application of rules to the A321.

It is not clear whether your arguments are against, the process or the judgements offered or in the application of the judgements to the process.

Did Airbus file any concerns over the Max and what specifically were or how were they disposed of in the certification process?

This board might consider if there are any flaws regarding either the max or A321 regulatory function and how they should be addressed

lomapaseo

On the 737 MAX certification, indeed there were not enough concerns properly communicated, within Boeing and then to the FAA, to change the course of the FAA decision. I mean, Boeing has admitted criminal responsibility regarding its role in the process (with regard to actions and omissions by two individuals in part of the process). And there are as you know reams of reports by qualified industry professionals (start with JATR and the list isn't a short one) about the failures.

But my post was not intended to suggest a comparison, and did not actually suggest a comparison, between the 737 MAX certification debacle on one hand, and the pending EASA decision on an Airbus aircraft on the other hand. I'm sorry if it is the case that I wrote it sloppy enough to be misunderstood like that.

The point was made, in some prior thread or threads, that professional engineers have an obligation to call something out, if it implicates safety or otherwise impacts their profession's standards. There were pretty strident assertions that this professionalism has lapsed in some places, with the MAX being a case in point. That being said, then when engineers -- and yes I've presumed that the comments by Boeing about the fuel tank design originated in whole or in part from engineers -- when engineers COMPLY with their obligation, what do some posters retort here? Oh, their company is tainted, never mind their concerns. Or if these comments don't overtly assert a "never mind' attitude, to my reading they surely imply it and leave it to readers to put into words.

So that's why I said, where's the icon for "don't shoot the messenger." If the engineering point is valid, and some knowledgeable posters here have suggested it is valid or probably is valid, then Boeing's departure from an engineering focus in the MAX and in general -- while deplorable and tragic and part of a pattern of corporate decadence -- also is irrelevant to the merits, to the design adequacy question.

Exactly. All these same posters saying that Boeing should mind their own business would be the first ones to demand, after a tragedy, why Boeing didn't speak up if they knew something was not safe.

Perhaps these posters should try a career in politics, as their hypocrisy qualifications seem to meet the required standard.

I don’t know. We see Boeing discounting and hiding details of their own designs in spite of their responsibilities, and yet finding time to raise doubt about another manufacturer’s design. Not for safety but for throwing darts and trying ( not successfully) to gain some advantage. Sure, like any member of the public, they are free to comment and we are free to comment in response. I wouldn’t call it hypocrisy. We aren’t hiding anything.

tcasblue,

Airbus are being (more than) transparent about the conformal fuel tank, maybe if Boeing were as transparent about the changes to make the Max 'work', specifically MCAS then perhaps there would have been reciprocity.

Anyway, good to know that Boeing are focused on safety.

Well if Boeing leaves the field who else is going to call the kettle black?

I might have an opinion on this but I trust Boeings experience in this a lot more.