Avian "thumb"

Usage examples of alula.

I let her glide, cautioning her to hold both alulae open with her thumbs for more lift at slow speeds, while barely sculling with her fingers.

We went back to the tourist slope and I let her glide, cautioning her to hold both alulae open with her thumbs for more lift at slow speeds, while barely sculling with her fingers.

I climbed to the roof with powerful beats, increasing my angle of attack and slotting my alulae for lift without burble -- climbing at an angle that would stall most fliers.

I completed my stoop in front of the gallery, lowering and spreading my tail so hard I could feel leg muscles knot and grabbing air with both wings, alulae slotted.

We went back to the tourist slope and I let her glide, cautioning her to hold both alulae open with her thumbs for more lift at slow speeds, while barely sculling with her fingers.

They're lovely -- titanalloy struts as light and strong as bird bones, tension-compensated wrist-pinion and shoulder joints, natural action in the alula slots, and automatic flap action in stalling.

But the alula opened properly and I decided I must have been overcontrolling, easy to do with Storer-Gulls.