Originally Posted by
vilas
Delta191 Lockheed 1011 fatally crashed at Dallas FW while going through a single CB on ILs path. That triggered the research to identify the vertical movement inside a CB. It triggers the warning when it crosses a certain threshold.
Quite so, added Dr Tetsuya "Ted" Fujita's name to our lexicon. (he passed away in Nov 98... )
The geometry of DL191's encounter is a major badness to the day at Dallas.
The alert inhibiting is quite smart in ir's own way, it should avoid the sort of question that has arisen in this thread... further out from the threshold increases the potential for getting a downflow to increasing tailwind event in a microburst. strategically, taking a hold is not a bad idea, but stuff happens to best-laid plans. Making a decision to continue while having a PWS blaring at the warning level would look pretty interesting at the subsequent court of inquiry. Assuming that you have a QAR type program you are guaranteed to be getting tea and biscuits from management who may not ascribe to your point of view. Reminds me of a discussion around the bar once when a newly minted driver was telling all 'n sundry around the table which of the companies policies he declined to follow by choice, which led to the laconic and polite comment by the Director of Standards,
"then, pray tell, what other company policies do you wilfully disregard?". The standard that would apply to a deviation from a trained response would be unless a greater emergency exists. To that end, describing the morning after that the landing with the raucous noise until inhibiting occurred was the lesser emergency would probably get the grey-haired guys at the table busy with their eyebrows... muppet style!
The conversation would be even more interesting if they are digging the gear out of the mud off the side of the runway...
Old Guys
runway offs come in various flavors and varieties... the one below had the crew asking for a tow truck... needed a bunch of bulldozers and angle grinders.
