While the Hawk is basically black, a 1/48 model would not represent the aircraft if painted true black.
Anything "black" at scale looks dark gray in sunlight. In this case, a very cool gray such as the color called "anthracite" which is a sort of metallic color and not reall dark because the minor inregularity in the finish coat reflects a lot of sunlight.
Also, Krylon is not quality paint. I would suggest a Testors spray can, or if you have an airbrush; NATO black color.
Bill