If I understand correctly "fixing" MCAS would be quick but audit found out more problems and Boeing started basically a refactoring of their computer architecture (including hardware changes) which itself takes a lot of time and didn't pass new audit yet.
Didn't I read from another hacker news poster that the software engineering and design was outsourced? Anyone know?
Delays in Boeing Max Return Began with Near-Crash in Simulator
61–70 of 199 posts
Re: Delays in Boeing Max Return Began with Near-Crash in Simulator
#62I thought the whole point was that you needed 3 computers monitoring each other because if you have only two, you can't tell which one is faulty and which one is correct. How can they make it work here ?
Re: Delays in Boeing Max Return Began with Near-Crash in Simulator
#63These should not fly for a decade. They're rewriting the avionics from scratch. This should require a years-long process of testing, external auditing, and approvals. I'd even go so far as to say in flight, we should require competitor review. That's right, no trade secrets. If you want your Hello World up in the air, you better let your competitor vet the source code. This is an engineering boondoggle and an embarra…
>>Software does not need to be this complicated. >>Design a damned airframe that's airworthy without needing stabilization hacks. In effect you are stating that you understand better than the hundreds of engineers involved with this project why these design trade-offs were made. Careful with that line of thinking. You're nearly guaranteed to be wrong. There are a host of reasons for the design in place: Efficiency, e…
While your line of reasoning is sound in most scenarios, in this case, the why is pretty obviously written on the wall. The overriding reason why this hacky-hack software solution was slapped into the airframe was to keep from having to reclass the plane following the addition of too-large engines. Your reasons listed played into the design decisions that became MCAS, but the underlying reason as to why any of this nonsense was needed in the first place is because non-engineers forced a shitty situation on the people who actually implement these airframes.
Hacker News is frequented by engineers from multiple disciplines, including software engineering, and many of those engineers know the kinds of terrible design decisions forced by management that come about to make a quick buck. People are pissed about it due to this fact, and rightly so.
Re: Delays in Boeing Max Return Began with Near-Crash in Simulator
#64Earlier quoted context omitted.
Big "disagree" alarm for the pilots and let them decide to keep either computer or go direct. Airbus has the concept of flight control laws, surfaced and changeable by the wet backups. http://www.airbusdriver.net/airbus_fltlaws.htm
Which computer calculates that there's a disagreement, and how can we ensure it's not indicating a false negative?
Re: Delays in Boeing Max Return Began with Near-Crash in Simulator
#65Earlier quoted context omitted.
Boeing makes up 8.8% of the Dow right now, the largest component. There is a lot of pressure from the finance community and the government to get this recertified to keep the stock market from going down.
Tough shit. Index funds may take a hit, but better a market crash than and airline crash.
Re: Delays in Boeing Max Return Began with Near-Crash in Simulator
#66The can of worms has been officially opened, and this may turn out to be a case study in how bad software and outsourcing your centers of excellence can bankrupt a company. If TFA is to believed, Boeing has embarked on a project to take what is currently a master-slave failover design and jury-rig it into a master-master real-time system. This is based on bad performance in the simulator—not because of MCAS—but while…
That, or this article missed the boat somehow. I find it hard to believe that a total redesign is happening and that they expect to be done by the end of the year. Either this article is wrong, or something is terribly wrong at Boeing.
Re: Delays in Boeing Max Return Began with Near-Crash in Simulator
#67These should not fly for a decade. They're rewriting the avionics from scratch. This should require a years-long process of testing, external auditing, and approvals. I'd even go so far as to say in flight, we should require competitor review. That's right, no trade secrets. If you want your Hello World up in the air, you better let your competitor vet the source code. This is an engineering boondoggle and an embarra…
>>Software does not need to be this complicated. >>Design a damned airframe that's airworthy without needing stabilization hacks. In effect you are stating that you understand better than the hundreds of engineers involved with this project why these design trade-offs were made. Careful with that line of thinking. You're nearly guaranteed to be wrong. There are a host of reasons for the design in place: Efficiency, e…
We don't know that any engineers approved this design. It could have been completely compartmentalized and approved by management only. We'll never know what the engineers said until there's a complete investigation and the engineers are subpoenaed.
Here's what we know so far about the 'engineers': 1) The MCAS software was outsourced. 2) MCAS as originally designed and submitted to the FAA didn't have enough authority to affect the plane in the needed amount, so Boeing increased it's authority and never told the FAA.
Point to speaks to a failure in basic engineering or a deliberate deception of the FAA. A competent engineering team should have been able to calculate exactly how much effect was needed before the plane left the ground. Sounds like they were winging it on this one.
Re: Delays in Boeing Max Return Began with Near-Crash in Simulator
#68These should not fly for a decade. They're rewriting the avionics from scratch. This should require a years-long process of testing, external auditing, and approvals. I'd even go so far as to say in flight, we should require competitor review. That's right, no trade secrets. If you want your Hello World up in the air, you better let your competitor vet the source code. This is an engineering boondoggle and an embarra…
Re: Delays in Boeing Max Return Began with Near-Crash in Simulator
#69The can of worms has been officially opened, and this may turn out to be a case study in how bad software and outsourcing your centers of excellence can bankrupt a company. If TFA is to believed, Boeing has embarked on a project to take what is currently a master-slave failover design and jury-rig it into a master-master real-time system. This is based on bad performance in the simulator—not because of MCAS—but while…
>Collins reorganized business units and retrained managers, with an eye toward efficiency and speed. It pushed its suppliers to do the same, and established partnerships with companies such as HCL Technologies, which provides outsourced, lower-cost engineering services from India.
>Along the way, Collins unseated Honeywell as the provider of flight control computers on a predecessor of the Max, the 737 NG, and supplied numerous systems for the Boeing 787, which went into operation in 2011.
>When Collins secured the contract for the Max displays in 2012, it credited the belt-tightening. “There were a lot of cost-saving measures — a lot of tough decisions — that had to be made,” one manager said at the time in a company publication.
https://www.nytimes.com/2019/11/07/business/boeing-737-max-c...
If there was a problem with the master-slave operation on the MAX, not necessarily connected with MCAS, might not the same problem exist on the 737 NGs?
Re: Delays in Boeing Max Return Began with Near-Crash in Simulator
#70Earlier quoted context omitted.
A split brain in a plane is a bit of a nightmare. I'm not sure how they can work around it with just two computers.
Big "disagree" alarm for the pilots and let them decide to keep either computer or go direct. Airbus has the concept of flight control laws, surfaced and changeable by the wet backups. http://www.airbusdriver.net/airbus_fltlaws.htm