Hahaha you guys were thinking of cartoons, but I was picturing the Terminator!
I do like the leather saddle idea, that could actually work, perhaps giving him enough protection to struggle free. It would have to be thick leather though, like welding glove grade not garment leather, cause hawk talons are SHARP.
If you’re really really determined to save him though, why not try some aversion training? Perhaps a hawk silhouette on a stick? Chase him around with it, make it scary, make him fear things that attack him from the sky. Your neighbors may think you’ve gone insane though lol
Most chickens are already naturally averse to flying predator shapes. Isn't this one? Even my tiniest chicks fled the open area, took cover and huddled together when a buzzard soared overhead.