Firstly, WOW. Considering you used an airbrush, it's really good! Did you use photoshop or SAI or something else? The shading of the wings is perfect, for a dragon that is. The shadows and light are in the perfect spots and compliment the picture completely.
(I'm not sure what they mean by vision and impact, so I just gave an average rating for those).
The landscape is OK i guess. It isnt the main subject so i dont really know hat to say. The sky shading and (im just assuming its smoke) smoke shading above the mountains is really good too.
The fire is a bit disappointing. it could have a more distinct shape instead of too much uniformity.
OVERALL: great work! i love dragon folklore (currently reading the lord of the rings, so yeah) xD