Oh, for the Love of, uh, "the deity of your choice"...if the thing was working properly and wasn't out of gas, they screwed the pooch. "The rain destroyed the lift!" I'd laugh if it didn't make me want to cry. How do you reckon millions of flights land in the dreaded RAIN every day? The largesse of Jupiter? I've flown through storms I'd have drowned in without the windshield, and the wings never magically stopped flying. No doubt the Feds will come out with an exhortation to avoid all rain in the future. Lulz.
Not the main thrust of my post, but I am still mindful of seven's comment.
You seem to discount the NASA research mentioned? This is specifically a low altitude/last minutes problem. When you consider the mass of the rainwater, it seems there is a time when it can't be accelerated appropriately over the upper surface, suddenly and severely disrupting lift.
My main point was how the groundspeed might have been affected.
It was never something I had to calculate or really even think about, but then, I was in old iron and the power levers were always in my hand. They would somehow move by the accelerative forces on my backside, long before any medium-term and meaningful change of airspeed was registered. A totally mysterious process, but one that requires some years of being in touch with real mechanisms.
Edit to ask: Do modern auto-throttle systems have accelerative inputs to predict responses?
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