Wow, a pilot AND a published novelist AND a concert pianist??
Any secrets you can let out as far as getting your book published? I have a novel that I can't get any agents to read.
I looked into the Van Cliburn Amateur Competition a couple of years ago. I spoke with a fellow physician who had done it twice. (He had not gone beyond the first round.) He enjoyed the experience, and said he met some interesting people. I've never entered, because I have gleaned that after the first one or two competitions, the ones who advance are mostly people who have things like master's degrees in piano performance from Juilliard, but are not working as professional pianists.
The rules say you can use a score, but you won't have much hopes of advancing or winning if you do.
I made a personal decision not to enter because I felt it would be too stressful (thus negating any reason for it!). But you might feel entirely differently, so follow your heart.
Good luck--
Teresa