Ops-Normal.org

If you close a space, surely it ceases to be a space?

I will concede to Slasher that the 727 was slightly good looking.

Not in the same class as the horizontal stab of the VC10 though. The proportions of that whole aeroplane were heartbreakingly gorgeous.

Piling on the pressure facing Boeing executives, just this week a US Federal Aviation Administration (FAA) official indicated that airlines' fleets of Boeing 737 Max aircraft might be grounded until the end of the year - longer than many had been expecting.

"The highest priority for us is the 737 Max's safe return to service," said Mr Muilenburg recently. Indeed, it has been a key seller for the US firm, which has roughly 4,500 unfulfilled orders for the aircraft.

https://www.bbc.com/news/business-48630188

Is there a point in time that it would no longer be worth to return to flight and bin the whole model?

There are 4500 outstanding orders, and Willie Walsh is considering it for Vuelling . . .

I imagine there will come a point when airlines start cancelling the orders. Presumably there are clauses for operability/delivery.

Here's one from a real pilot, for the benefit of Congressman Sam Graves (self-appointed skygod)

I recently experienced all these warnings in a 737 MAX flight simulator during recreations of the accident flights. Even knowing what was going to happen, I could see how crews could have run out of time before they could have solved the problems. Prior to these accidents, I think it is unlikely that any US airline pilots were confronted with this scenario in simulator training," Chesley "Sully" Sullenberger told the House Transportation Committee during a hearing on the embattled plane model.

As aircraft, and machines in general, become more complex, troubleshooting becomes more difficult. It is especially difficult with the increasing role of software, since the experts in software design may have very little understanding of aviation as a trade. Indeed, exporting software design to countries like India may mean the guy programming a widget may not even have ever been in an aeroplane. The same is true of all highly complex technology, like medical imaging. I used to give my students, 15 years ago, the example of someone who programmed and helped with design of imaging scanners, typically for use by surgeons in real time during operations. She had trained as a doctor, but also had degrees in physics and computing. She was paid $20,000 per day, plus expenses, and had work coming out of her ears. She charged more for jobs in places she didn't like. She could talk to the surgeons, the scanner builders, and the programmers, all in their own language and understanding their nuances. Every job she did worked out cheaper than the big teams of specialists, in most cases who had already failed. However, major companies like Boeing are not about to employ, or even train up, such people. This is because they tend to have to tell higher execs that they are, and have been, idiots.

Apparently Scarebus has the shits with Boeing after the latter flogged a heap of MAXs to Birdseed's owner at Paris.

https://www.bloomberg.com/amp/news/arti ... 7-max-deal

The latest - simulator testing apparently has discovered a possible micro-processor issue according to the FAA
From CNN:
"In simulator tests, government pilots discovered that a microprocessor failure could push the nose of the plane toward the ground. It is not known whether the microprocessor played a role in either crash.
When testing the potential failure of the microprocessor in the simulators, "it was difficult for the test pilots to recover in a matter of seconds," one of the sources said. "And if you can't recover in a matter of seconds, that's an unreasonable risk."

Gosh! These are probably US Skygod pilots too. What hope the ET and LionAir crew....?

News this morning is that the FAA boys have found a secondary-but-related problem in the Max. Keeping very tight-lipped, but rumors have it that Boeing's software fix is overwhelming the 'computer', whatever that means.

The MCAS runs off one of the two main flight computers, each receiving data from one AoA gauge. The fix will probably involve sharing data between the two computers in order to cross-check the AoA gauges, which the computers were not designed to do to this extent, which is doubtless why the original designers decided to go with just one flight computer feeding the MCAS in the first place. The easiest design solution may be to add a separate computer for the MCAS taking feeds from both flight computers, or a separate computer to aggregate and cross-check the feeds from the two AoA gauges, which then feeds both flight computers.
Substantially modified or new flight computers will likely require complete recertification, and there will be strong doubts as to whether the MAX will pass a certification process done properly with the World watching. I strongly suspect the MAX won't be flying before 2020 at the earliest. Add in the manual trim problems (full redesign needed there also, I suspect) and the legal cases, and it may never fly again.

OFSO - are you reporting another problem or is is the same one? IFSO OFSO can we have a link or quote?

Fox - I do not think that is either the problem or the solution! As far as I understand it there is some unclear issue with the ability to use the yoke trim in a run-away situation.

From Aviation Week:

"response to the electric-trim inputs took too long. They had a difficult time quickly resolving the situation"

We are all stabbing in the dark here since Boeing have not exactly been forthcoming with how this **** system works, and if there is, as suggested, some software between the thumb and the tailplane, and that is malfunctioning, heaven help us. There is sufficient 'fog' about the actual events on both the ET and the Lion run-aways to make the situation any clearer.

Well, if that's not the the problem, then mine won't be the solution
That said, there probably is a problem with using both AoA feeds for the MCAS, otherwise the original designers would probably have done it.

Fox3WheresMyBanana wrote: ↑

Thu Jun 27, 2019 12:34 pm

That said, there probably is a problem with using both AoA feeds for the MCAS, otherwise the original designers would probably have done it.

It cost money !

If they're both physically connected then there's no additional hardware cost. However, I suspect that certifying the software to show how it handles both inputs would have been more complex, as they're finding out now that they're doing it properly.

I saw the comment on the BBC that they've found another problem. I forget where I saw it but there was a mention of bad things happening if the black box responsible for MCAS failed, possibly in the absence of something sensible happening it defaults to something dangerous.

I think the problem was, as has been said, that if you use '2' inputs you should compare them and do something if they are out of kilter. The odds of one or other triggering such were probably assessed as 'too high' and would also mean, presumably, 'Land ASAP'- and, of course, would require TRAINING - whereas a system using "1" that you can sneak in without telling anyone.............just kills a few

All together now "MONEY MONEY MONEY....."

As llondel says above, it was on my BBC feed on the phone. Read over brekkers and then had a paper to write so put it aside.

More Worms crawling out of the can?

https://m.sfgate.com/news/article/Long- ... 055084.php