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Originally Posted by CraigSca
Still reading this - awesome that you've had the stamina to keep writing!
Did you learn anything new when you took the meteorology training? Knowing how wind shear can effect a landing, how does one compensate for the early additional lift and then, of course, the downdraft? Is wind shear during a landing an automatic go around, or does one attempt to land anyway?
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Part of getting my CFI (Flight Instructor) rating is going through, and then teaching a large amount of meteorology. I would say that's where the bulk of my knowledge comes from. But then after I stared flying as a career you pick up a lot more that deals with high altitude stuff and you focus more on the larger US weather picture instead of just the local stuff that impacts flight students most. I did learn how to better utilize the weather program on the ipad to get more accurate reports on turbulence potential hazards enroute though.
Wind shear can be deadly. It's defined as a shift in wind of more than thirty knots. An example would be a situation where I might have a tailwind coming down an approach that then changes to a headwind somewhere closer to the ground. It doesn't happen that way much, but it can happen. I had a situation taking off out of JFK a few years ago where we were climbing out into a layer of shear and had to go to max power and even then, we were only just barely climbing. We couldn't make any turns in that situation until we had climbed out of it.
On landing the situation that you describe is what you might find under a large thunderstorm, or what we might call a microburst. It was the primary cause of the Delta crash in Dallas in 1985.
Technology and awareness have improved a lot since then. It's something that we train on a regular basis and are aware of. I generally don't like bringing the power back much below 52% on approach and it's one of the triggers that I use to keep track of my situation. A situation like Delta faced was the headwind like you described, and where they were way above the ILS glidepath. The result was that they got fast and high, pulled the power back to idle and then when the tailwind hit, they were way behind the power curve, lost all their airspeed and couldn't recover.
They talk about approach gates at 1500ft, 1000ft and 500ft. There are certain approach stability standards that have to be met and if those are not met, then a go around would happen. Recognition is the key, and a smart crew will go around long before they get into that situation now. The tower is much more aware as well. Newer technology now reports when there are wind shift discrepancies for each and every runway on the field. That technology doesn't exist at every airport, but it is out there.
Typically, you might start an approach and if a wind shear report for your runway of greater than 30 kts is alerted then an immediate go around would be required. If nothing was reported, but something alerted you on the approach, say you got really high and fast, you would go around. Safety has improved greatly over the last 30 years and it will continue to be pushed by pilots. We want to get there just as badly as you do.