Dick Francis certainly has a gift of writing well; his characters are pleasingly 3-dimensional, his heroes undergo real problems but are stoic and brave, he can build real tension and tells a pretty good romantic story, too. There is not much to beat a good Francis for an airplane ride, or for when you're sick for that matter - you just read about the way the Francis hero takes his pain, and you feel better already!
Rat race (written in 1970) is a gem even among good Francis books. It's got a pilot ferrying jockeys around, so you get both the horse-racing (which Fracis can make sound really good, even for a non-race goer like me) and the flying; there is a in-the-air sequence here that will nail you to your seat. And the love story is really good, too; again, because he can make his characters so real, through just a few deft descriptions and some easy dialogue, that you find yourself taken along for the ride (sorry).
A top story, from a top writer.