It is my understanding (or interpretation, might be wrong though) that there were two main issues:
1) Cascading indications, that were not necessarily representative for the failure at hand. And therefore Checklist/NNC selection was not intuitive.
Such may not be problem with a low risk failure (such as IFSD) where - apart from uncontrollable engine fire – time is not most critical. But would not fly on a high-risk failure scenario (Catastrophic category) such as runaway MCAS/trim.
2) Cascading failure scenarios, not necessarily related to each other. Checklists/NNC were considered not sufficiently aligned with cockpit indications and/or vice versa.
This is were EICAS would be most helpful.
Is it understanding/interpretation, or intuition? It's hard to interpret so much from the little we've been given, IMO.
Regardless, for the sake of argument let's go with your interpretation, and such an interpretation is quite problematic for Boeing.
As I wrote several times my interpretation is the "cosmic ray fix" wasn't simple but it was relatively straight forward and was well covered by prior art in the computer science field. It sounded messy, but really you were keeping the core logic of the system intact and just adding some comparators to the edges of the system and improving the existing active/standby mechanisms to handle an active/active system. You weren't, for instance, changing the logic of the autopilot or automatic landing system. If
it turns out that these "extensive errors" can't be fixed by more focused training and needs something akin to EICAS, my interpretation would be that it's a huge problem for Boeing. We know P-8 is based on 737 and has an EICAS, but P-8 was developed right from the start with the decision to do EICAS in place so all the required changes to bring the required information into the unit were made before the first one was built.
I was going to type in more, but google led me to a ST article:
However, Boeing’s 737, its oldest jet, doesn’t even have EICAS. Behind its sleek-looking pilot flight displays, the jet’s legacy avionics systems have been upgraded piecemeal over 50 years, and the overall system architecture won’t support EICAS.
Installing EICAS on the 737 “would be challenging,” said Mike Carriker, Boeing’s chief pilot for product development, in a brief interview. “There aren’t enough sensors on the 737.” Even if it were possible, it would require a new type certificate and new pilot training.
During development of the MAX, Boeing’s customer airlines made clear they don’t want to pay for such an upgrade.
Ref: https://www.seattletimes.com/business/b ... le-alerts/
It also echos what I said about the bar being raised for future approvals:
Schulze said the NTSB is also recommending that the FAA develop new improved alerting systems that give pilots a clear priority of what to do, for example, telling them which checklist they need to run first when different error messages pop up at the same time.
“EICAS does some of that. We think we need to go to the next level,” Schulze said. “We want to see the FAA work with the manufacturers and human factors experts to develop a better design standard.”
That’s a future aspiration.
Boeing's CEO stated concerns about the need for changes in the cockpit was one part of why Boeing shelved NMA.