Originally Posted by
Loose rivets
Grebe also links to another Seattle Times report. The internal politics is a frightening subject, but because of my years in electronics I'll just probe the proposed design concepts.
The idea of synthesised airspeed has long been thought-provoking but the units protruding from the fuselage haven't remained there all these years because the alternatives were easy/reliable. They are one of the earliest detection devices in aviation and their limitations are well understood. However, the issue about the article is that some folk are protesting loudly that certain design advancements would have saved the day? Surely, that's not the point.
MCAS in its original form has a certain logic but it's what happened after 2017 that the real error was made. (That, and not telling most of the world about it.)
Given that MCAS was rewritten is in my opinion the most serious issue in the whole debacle. Yes, taking the data from a single unit broke the rules about one item being able to cause a 'catastrophic' incident, but I'm not quite clear if it would be deemed so if MCAS had not been rewritten. It took the latter to qualify the former. Perhaps.
The lack of an AoA display in the MAX is not a major issue. However, not having a comparator warning, most definitely is. At some stage they found out it was non-functional, yet deemed it something that could be done in the next update. I'm still not totally clear if the comparator would work as a stand-alone device, but let's face it, one small word-group in pale lettering is not exactly the best attention-grabber.
The main issue to me is not what modern electronics could have done to save the day, it's simply what was radically wrong with the system supplied. When they added a single input logic to the rewritten MCAS, everything changed. Let's not forget that the two fatal losses of AoA data, were technically completely disparate failures
Interesting- but IMHO- the ' recent " ( last two or three decades ) development of inertial nav systems that fit in a shoebox has made an non sensor AOA euivalent practical. In simple terms- one calibrated between pitch ( floor angle ) or gyro horizon, and level flight AOA, the Inertial system the can be used as a indepndant AOA ( not quite as accurate as actual, but close enough to discount maybe a 5 degree AOA from a real 2 degree AOA with a second, etc.
I suggest you take a close look at Boeing
https://www.isasi.org/Documents/libr...ducing-787.pdf page 38 and on
And another Boeing pub ( cant find the link )
OPERATIONAL USEOF ANGLE OF ATTACK
ON MODERN COMMERCIAL JET AIRPLAN