RE Numerous posts
Safety vs cost and who decides: Black boxes have nothing to do with safety other than supplying new knowledge to prevent a similar future event. Ingenuity as per IanW, not bales of money, should be aimed at crash location improvements. But focusing money, attention, and ingenuity on wreckage location is attention not aimed directly at accident cause. Crash location improvements directed by hindsight have to wait for identical circumstances to recur, but even then black boxes cannot fully inform about the nature or extent of pilot confusion.
While holding the interest of many (including me), exactly how 8501 impacted the ocean is in many ways irrelevant to 'safety' because final impact most resulted from loss of control long before. Impact speed and attitude were not chosen by the 8501 pilots (unless Mr Snuggles is on to something). Falling leaf, spin, flat spin, or other descent profiles are mostly irrelevant because pilots don't train for them and pax jets aren't designed to complete or withstand recovery from them.
Accidents are ~0.001% (or pick a tiny %) of all flights. Some accidents such as airframe failure resulting from completely unforeseen forces or airframe inadequacies are unavoidable, but they get included in the 0.001%. 'Normal' rarely applies. What does usually apply is a confluence of events/circumstances peaking, like ocean rogue waves, in a very short amount of time, from a few seconds to hardly more than a minute. The last opportunity to avoid an accident is the time between the next to last and last decisions in a short chain. Accidents seemingly surrounded by normality, and accidents of an exceedingly rare confluence of factors, both share pilot confusion and inattention as high ranking primal causes.
One improvement would be better real time wx information (Langleybaston and ATC Watcher) to avoid the series of brand new surprises involved in 'picking your way through'. But there are numerous previous posts about the current limitations of both equipment and the operators of that equipment. Horizontal separation of five or fifteen miles from preceding flights no guarantee of identical weather.
The best solution would be to focus attention on how to elongate the time available to pilots to react to conditions to enable good decisions, better real time wx being one aspect. Time elongation is otherwise currently and systemically limited by both a very narrow range between overspeed and stall, and by momentary (where 60 seconds is a long time) failure of necessary instrumentation or agreement of automation components. More pilot time for thinking would prevent some accidents, time not currently available as events prove. My point is that accident prevention can't ignore the coffin corner of time, so while time needs to be addressed, the impediments are systemic. IanW's last paragraph in 1784 also applies.
Great set of Flt 1549 pics in MrSnuggles posts! Actual Utoob videos of the event show the angle of fuselage to water, which was notably glass smooth. The same impact angle where the point of impact chanced to be 20-30' fwd of that of 1549, and with the impact being not glass smooth but a 15' swell/wave instead could have holed the fuselage bottom of 8501 and directed a torrent of water into the fuselage, overpressuring the upper fuselage, parting the lower half of pressure bulkhead, and carrying away the aft floor, horizontal stab mounts (which escaped in 1549), FDR and APU. A lot of "could have's" remain.