Help with Sky Colour

[JigsawMan]

Hiya folks. Stopped off at an airshow yesterday, sky was a dull grey so most of my shots don't looks so great. I have put one below so you can see what I mean. Any ideas how I can improve the colour of the sky in Photoshop?

cheers!

J.

 

[Peniole]

Bump up the saturation of both red and blue, that might do it, the plane would improve too.

 

[Flash Harry]

Make it smaller to fit the screen.H