DS-ing....BIRDS

[CactusJackSlade]

The other day as I was driving along and watching the wind strength and direction (anticipating flying later that afternoon ) I noted 2 turkey vultures headed down wind my direction.

I waited at the stop sign until they came near just because I always watch what birds are doing... and the suddenly they dove down behind (on the leeward side) of a large stand of tightly packed trees, maybe within 10 feet of the ground the they turned 180 degrees, popped up over the tree tops, did another 180 and dove down behind the trees again picking up speed. They did this 3 times and then shot off down wind again.

Humm I thought to myself... I think I just saw birds DS-ing???! Wow, pretty cool, we don't think that HUMANS discovered DSing do we??!!

L8R,

CJS

[bjaffee]

Actually, even the term "dynamic soaring" comes from birds. It was first observed in albatros quite a long time ago. Though, they do it in a rather different way then we do.

[CactusJackSlade]

Yea,...

They probably slow down before their feathers start popping off! ;-)

Yes, I guess I did hear that before about the albatross... never thought I'd see it here locally though...

CJS

[bjaffee]

I've heard people mentioning seeming small birds (finches), DS'ing. Though, I'm still not entirely sure it's intentional, or if they are just darting in and out of the boundry layer chasing bugs.

[Daemon]

I think the finches and swifts do it intentionally. They may be hunting at the same time, but they know a good thing when they see it, and I've seen one go around for several minutes without flapping once, as it buzzes back and forth over the top of a ridge line late in the day.

I've also seen them turning DS loops over barn roofs and vertical loops in and out of the little calm space between two buildings when the wind's blowing over the top.

Sometimes when I'm flying up on Mt. Zion a swift will buzz by a few inches from my ear (I swear they do that on purpose) and then go after the glider for a while. I actually had one chase the Bluto through 2 or 3 lazy DS turns in a row. He was keeping up by pulling quita a bit tighter turns.

Turkey vultures are one of the few big soaring birds to be seen flying on the lee side regularly. I've never personally seen them turning true DS loops but I do see them flying the upflow from the rotor all the time. I've seen em just float around on top of the rotor for 15 minutes or more without a single flap. They make it look like it's glass smooth back there. Funny, my gliders never think that's the case. ;)

ian