E.U.’s Biggest Economies Ban Boeing Max 8 Jets • Hacker News Board

Re: E.U.’s Biggest Economies Ban Boeing Max 8 Jets

#361

Post by cco » Wed, Mar 13, 2019, 6:46 AM UTC

joe_the_user wrote: post #276

anovikov wrote: post #267

Earlier quoted context omitted.

Obviously stability has to be achieved through fly by wire tech. Doing it through natural aerodynamic stability is a waste of resources of insane proportions as such airframes induce more drag and burn more fuel. If this sounds too scary for people in a forum of software developers it only puts a shame on our profession, from ourselves.

No one knows better than software engineers how difficult it is to make inherently reliable software and how much complexity can add to the difficulty of making reliable software. That said, the cost of not using latest fuel efficient airplane would indeed be huge and the actual reliability of modern aircraft is very high and has been increasing over the years in which fuel efficiency also increased. Sometimes, human…

Could you clarify your assertion that it would be massively more expensive?

A quick look at the numbers suggests that a 737 MAX 8 is about 10% more efficient on fuel burn compared to a 737 300. That is not "massive" in my book and I'm more than happy to pay a little bit more per ticket if it means a higher safety margin.

Did you mean something older and less efficient than a 737 300?

Re: E.U.’s Biggest Economies Ban Boeing Max 8 Jets

#362

Post by kakaorka » Wed, Mar 13, 2019, 8:02 AM UTC

cmurf wrote: post #335

zaroth wrote: post #312

Earlier quoted context omitted.

That’s a great explanation, even if it is oversimplifying. We don’t build planes with training wheels anymore because the performance cost was too high. Planes are still the safest way to travel even without the training wheels. I don’t think 737 MAX 8 pushes the envelope too far. I think they screwed up on re-training the disengage, and they may have screwed up on redundancy by only using a single AoA sensor, but I…

There are two alpha vanes on 737s, including the MAX 8, that measure angle of attack. Also we don't know the exact source of the error (in the Lion Air case; in the Egyptian Airlines case we don't know at all). The vane itself could be the source or some other part of the system.

I think you mean the Ethiopian airlines case, not Egyptian.

Re: E.U.’s Biggest Economies Ban Boeing Max 8 Jets

#363

Post by cmurf » Wed, Mar 13, 2019, 9:02 AM UTC

Reason077 wrote: post #110

dahdum wrote: post #103

American and Southwest Airlines are still flying the Max 8/9, and are refusing refunds (Southwest/American) and charging change fees (American) for customers concerned for their safety. I don't understand this logic. They are essentially risking their entire company over the safety of this plane. If something happens now they'll be driven to bankruptcy at record speed.

One thing to note is that both American and Southwest's 737 Max aircraft are configured differently to those flown by most other operators, with regards to the display of AOA indicators and the "AOA DISAGREE" warning light. These features are optional and the fact that they are not present on Lion Air's aircraft may have contributed to that crash. https://theaircurrent.com/aviation-safety/southwest-airlines...

Optional deconfliction UI for flaky angle of attack sensing? That's a indictment of the standard deliverable. Is this option free or do you have to pay for it?

Re: E.U.’s Biggest Economies Ban Boeing Max 8 Jets

#364

Post by cmurf » Wed, Mar 13, 2019, 9:02 AM UTC

kakaorka wrote: post #362

cmurf wrote: post #335

Earlier quoted context omitted.

There are two alpha vanes on 737s, including the MAX 8, that measure angle of attack. Also we don't know the exact source of the error (in the Lion Air case; in the Egyptian Airlines case we don't know at all). The vane itself could be the source or some other part of the system.

I think you mean the Ethiopian airlines case, not Egyptian.

Yep! Thanks for the correction.

Re: E.U.’s Biggest Economies Ban Boeing Max 8 Jets

#365

Post by Sohcahtoa82 » Wed, Mar 13, 2019, 5:41 PM UTC

shaki-dora wrote: post #177

sandworm101 wrote: post #158

Earlier quoted context omitted.

HN is slowly walking towards facebook culture. People up/down vote things they like or dislike, with the goal of disappearing opinions with which they even mildly disagree. Valid points and thoughtful discussion are increasingly unwelcome. Lol. Thanks for the downvote all below. Thanks for proving my point about the change of behavior.

Facebook doesn’t even have a downvote option.

It does on some pages' comments. It's a feature they're slowly rolling out.