Ehehe. Free soul.

Glitch, I assume? I didn't even hit it, and was in the wilderness so, no powerful NPC one shot him or anything. Just landed, and dropped dead.

Haha sweet.

Did you get a chance to see his health bar before he croaked?

May have taken damage from NPCs before you encountered him.

Perhaps fall damage got him?

He must've forgotten to deploy landing gear.

I'm thinking fall damage. Maybe his script had him "land" in the air, then fell -hard-. I didn't think he was that high up, though.

Never happened to me

Though one Dragon glitch I noticed was and invisible Dragon. 95% time he was invisible. When I attacked him with a bow, he started bleeding, and I could see where he was at.
When I killed him, he didn't give me a Dragon Soul or any drops, because I couldn't search him. He just died and didn't turn into a skeletal Dragon (though I couldn't even see him turning into a skeletal, since he was invisible).

I have had dragons randomly fall out of the sky beside me. And they were dead before hitting the ground.. A glitch?

This happened to me once. It was night out and I saw a dragon circling overhead then he saw me and eventually landed and right when he did a 2nd dragon lands hard and fast (you could hear him roaring and stuff) then he just drops dead 0_o :shrug:
Like Zydrate said free dragon soul lol

invisible cliffracers got him obviously

I've had dragons die and I didn't get their soul, I've had dragons die but never burn up to bones but still work properly otherwise (you can loot them and got a soul), I've had dragons seem to die pretty much with one hit, perhaps they had low health or I'm just getting that badass.