>. If the incident had been sudden onset of thick toxic smoke
Pinpoint "seems reasonable" changes like that without regard for the whole system of interactions are what sank Thresher.
The "sudden onset of thick toxic smoke" is rare. It's either not that toxic or the onset isn't that sudden. You can't just design the system based on assumptions of needing to cover a rare corner case without taking a look at the whole general thing and the frequency of various anomalies and crunching the numbers to see if you're not actually making it worse. I agree that the masks should be simple and reflexive but you absolutely could compromise the whole system if you prioritize reflexive over other attributes without actually taking a full stack look at the tradeoffs in all areas. Aircraft manufactures employ people to think about this stuff and they're frequently why "seems reasonable" changes don't get made.
That's true and part of the reason designing for aerospace applications is tricky.
That sort of thing is also one of the legitimate reasons the FAA can have for not adopting an NTSB recommendation. Requiring a seat for small children is one of those calculations. The FAA ran the numbers and assumed some portion of those parents wouldn't fly and of that portion some would drive. Some portion of flights are for physical or emotional health that would not be handled (you can calculate the increase in suicides from things like missing a loved one's dying moments). And of course driving is way way more lethal. So you have to weigh the deaths from not flying plus deaths from driving against deaths avoided if lap children were prohibited.
Pinpoint "seems reasonable" changes like that without regard for the whole system of interactions are what sank Thresher.
The "sudden onset of thick toxic smoke" is rare. It's either not that toxic or the onset isn't that sudden. You can't just design the system based on assumptions of needing to cover a rare corner case without taking a look at the whole general thing and the frequency of various anomalies and crunching the numbers to see if you're not actually making it worse. I agree that the masks should be simple and reflexive but you absolutely could compromise the whole system if you prioritize reflexive over other attributes without actually taking a full stack look at the tradeoffs in all areas. Aircraft manufactures employ people to think about this stuff and they're frequently why "seems reasonable" changes don't get made.