Hey, Zach, good to see you out there.
Since you're pleading complete ignorance of the term, I'll throw in a quick mini-lesson:
Three, yes, three, different kinds of lift! You're really getting your money's worth for your question.
- There is the hydrodynamic lift that is created on the windward surface of the keel, just as lift is created on the upper surface of an airplane wing, which "sucks" the keel to windward when under way and fights leeward drift, illustrated by this diagram. You have to imagine looking up from under the boat: I find that holding my breath helps.
- There is also aerodynamic lift, created when the wind passes over the outer surface of the sail, also shown in the diagram.
Now more to your question: why the wind shift itself is called a lift.
I'm just taking a stab here, and could very well be schooled by someone who knows, but the word lift seems to me
to refer to the ability to "lift" (or point "higher") the bow of the boat as a result of the wind shift, and so, like the term "point higher," is being used metaphorically, not literally (nothing is actually going up
or is higher
than before. I imagine the term was brought into use without reference to tell-tales, but I don't know how old or universally-used tell-tales are/have been. I'll be happy to be clobbered on this one.
How are your plans going? Would love an update.
I was typing while John posted: he says what I say, but more economically.