[SeaSeaRider]

There is a debate to be had, but this is a naked propeganda piece. The crux of the article is based on:

“Among Boeing’s critics is Gregory Travis, a veteran software engineer and experienced, instrument-rated pilot who has flown aircraft simulators as large as the Boeing 757.”

... someone who uses flight simulators. This is not credible journalism.

[ben7799]

Exactly... it's not clear if the author of the article is even an engineer, and he's speaking authoritatively on something. good engineer doesn't even speak authoritatively outside their specific area of expertise.

And the author's source is someone who is not an aeronautical engineer and has never flown any airliners apparently.

As a software engineer, I would never consider myself qualified to declare an airframe good or bad.

[mschuster91]

> ... someone who uses flight simulators. This is not credible journalism.

When talking about "instrument-rated", this most likely means a real rating certification. As for the flight simulators, best class "Full Flight Simulators" actually allow for zero "real" flight time for type rating transfers, as well as being actually used for the required regular training of airline pilots (per https://en.wikipedia.org/wiki/Full_flight_simulator)

[inferiorhuman]

When talking about "instrument-rated", this most likely means a real rating certification.

It is a real thing, but he's not type rated on a 737 and it shows. He and eetimes get a number of things plainly wrong. The article was mostly content-free clickbait and I'd encourage you to simply flag it.

[ackfoo]

Hatchet. Job.

An article written by a non-pilot about an article by a GA pilot with no experience as an ATP.

The elephant in the room is not the type-rating issue so much as the speculative cause of the crashes: if your aircraft is out-of-trim and control pressure cannot restore it, you have a runaway trim condition and you need to disable the electric trim system immediately.

If, in these cases, it turns out that the AOA sensor was faulty, that is only one of many possible causes for a runaway trim condition.

The core problem is not the specific cause, but the failure of pilots to respond appropriately to a common and easily-remedied situation.

[TheCondor]

We are armchair engineering the issue on hn, can there be “credible” journalism on this?

I feel for the engineers involved, I assume they all had good intentions and did their best. This seems like one of those things we’d read about in 2030 where some clever engineering and software allowed Boeing to fend off the rivals for a fraction of the cost, or likewise it took them to the brink of survival. As startup and entrepreneur people, we live this stuff daily with smaller stakes, I can’t help but sort of admire their attempt.

[rootusrootus]

The amount of armchair engineering going on here on HN about this particular issue has been disappointing, but educational. I've seen a couple of very good technical write-ups about what's really going on with MCAS, and by my guesstimate probably 90% or more of what is said on HN about this issue is factually incorrect right from the start.

[karmelapple]

Any links handy to help us learn more about what's really going on with MCAS?

[tim333]

I was thinking 'faulty airframe' was a bit over the top. OK the stall characteristics seem not ideal but I'm sure a lot of planes have aerodynamics that are not ideal in places. I'd be happy enough flying in one if they turn off the MCAS gizmo.

[clawoo]

The article reeked of anything but credible journalism as soon as it opened with "The saga of Boeing’s 737 MAX serves as a case study in engineering incompetence, and in engineering ethics – or the lack thereof."

By this point's it's obvious to everyone that the engineering of the plane is pretty far down the line of causes which lead to this.

There was a Twitter thread[1] a few weeks ago which explained it very clearly:

Some people are calling the 737MAX tragedies a #software failure. Here's my response: It's not a software problem. It was an

* Economic problem that the 737 engines used too much fuel, so they decided to install more efficient engines with bigger fans and make the 737MAX.

This led to an

* Airframe problem. They wanted to use the 737 airframe for economic reasons, but needed more ground clearance with bigger engines.The 737 design can't be practically modified to have taller main landing gear. The solution was to mount them higher & more forward.

This led to an

* Aerodynamic problem. The airframe with the engines mounted differently did not have adequately stable handling at high AoA to be certifiable. Boeing decided to create the MCAS system to electronically correct for the aircraft's handling deficiencies. During the course of developing the MCAS, there was a

* Systems engineering problem. Boeing wanted the simplest possible fix that fit their existing systems architecture, so that it required minimal engineering rework, and minimal new training for pilots and maintenance crews.

The easiest way to do this was to add some features to the existing Elevator Feel Shift system. Like the #EFS system, the #MCAS relies on non-redundant sensors to decide how much trim to add. Unlike the EFS system, MCAS can make huge nose down trim changes.

On both ill-fated flights, there was a:

* Sensor problem. The AoA vane on the 737MAX appears to not be very reliable and gave wildly wrong readings. On #LionAir, this was compounded by a

* Maintenance practices problem. The previous crew had experienced the same problem and didn't record the problem in the maintenance logbook. This was compounded by a:

* Pilot training problem. On LionAir, pilots were never even told about the MCAS, and by the time of the Ethiopian flight, there was an emergency AD issued, but no one had done sim training on this failure. This was compounded by an:

* Economic problem. Boeing sells an option package that includes an extra AoA vane, and an AoA disagree light, which lets pilots know that this problem was happening. Both 737MAXes that crashed were delivered without this option. No 737MAX with this option has ever crashed.

All of this was compounded by a:

* Pilot expertise problem. If the pilots had correctly and quickly identified the problem and run the stab trim runaway checklist, they would not have crashed.

Nowhere in here is there a software problem. The computers & software performed their jobs according to spec without error. The specification was just shitty. Now the quickest way for Boeing to solve this mess is to call up the software guys to come up with another band-aid.

I'm a software engineer, and we're sometimes called on to fix the deficiencies of mechanical or aero or electrical engineering, because the metal has already been cut or the molds have already been made or the chip has already been fabed, and so that problem can't be solved.

But the software can always be pushed to the update server or reflashed. When the software band-aid comes off in a 500mph wind, it's tempting to just blame the band-aid.

[1] https://threadreaderapp.com/thread/1106934362531155974.html

[rootusrootus]

This is an excellent analysis, thanks! Wish I could upvote more than once.

[salawat]

Succinctly put. Ship it!

[ReptileMan]

I am not sure it even uses the term airframe correctly. And it is not faulty. Probably case of we have not had a boeing bashing hot take in 48h find someone that speaks vaguely pilot lingo and interview him.

[rootusrootus]

Even better, he's a software engineer, or in other words exactly the kind of person who likes to armchair quarterback real engineers.