I’ve always believed thermaling slower than minimum sink can be worth a small penalty if it helps you stay in better lift more of the time. Same for banking 60+ in strong narrow cores. Not that either is always the best idea, but sometimes they feel too good to resist, and in fact I have outclimbed a lot of pals that way.
General soaring wisdom says thermal no slower than the min sink for your angle of bank plus a knot or two for better control; and more than 45 degrees is too steep to do much good. Fair enough, but that’s General wisdom (like Einstein’s General theory compared to his Special one, only lightyears dumber). Soaring wisdom of the Special variety says do whatever works and pay the fine only if you’re caught. Longstanding rules of thumb are worth their weight in piñatas, but like distance, speed, and even altitude records, they’re ultimately meant to be broken. The world is filled with fascinating examples.
If you spend enough time watching ravens in thermals (which I obviously haven’t, ‘cause I still do it every chance I get) occasionally you’ll see one circling as usual, except with both feet hanging down. It looks kinda goofy, but if we’re honest, so does nearly everything we don’t understand.
Ravens may fly like that for no reason other than they want to, the way kids jump in puddles walking home from school. But don’t be fooled, the goofiness those two species share is a symptom of formidable intelligence seeking an outlet. When we see ravens (or kids) daily committing half of the seven deadly sins, that’s genetic programming at play. Genius in the making. Keep an eye!
Might a raven’s flying with gear intentionally down be something more than birdbrained folly? If a car’s antenna adds measurable drag to a ton of steel, those dangling legs and long claws must add more to a two-pound bird by orders of magnitude. I say there has to be some material benefit.
Here’s one. Where is it written that drag is always a bad thing? That’s like not wanting brakes on your bike ‘cause they’ll only slow you down. Remember, drag pulls you back – horizontally that is – but not down down.
If you could reduce speed without raising angle of attack or interrupting uniform flow over the entire wing, it would allow tighter turns to hug stronger lift in the thermal’s core. Of course slightly slower airspeed will also produce slightly less aerodynamic lift, but what if there’s a wee numerical sweet spot between these concepts, akin to the one between min sink and best L/D? If only we had a way to cause a hair more drag without decreasing aerodynamic lift…
So here we go. I’m probably wrong about this, but it’s a puddle I’ve always longed to jump in. Why not try lowering your wheel in a thermal once, only for the climb, just to see if maybe those ravens know what they’re doing? If it turns out to be a mistake it won’t cost much, and who knows, you might even learn something. After all, birds have been doing this a million times longer than we have!