We really like the idea, the general concept. I would say you are definitly on the right track.
Can you try a few adjustments :
1) maybe do different versions, one with a glider, one with a helicopter and one with a parachute jumper (the purpose of the website is for planes but also for those other sports)
2) try to avoid the look of a "book" . It reminds us of wikipedia and isn't good for the image of the site, we are thinking more of a logbook which in real life looks like this :
http://goo.gl/LpxI3) can you try with different colors ? We like those but maybe as an artist you have a different input on it, if we don't like it we'll tell you to focus back on the current colors
4) I'm not a huge fan of the font, could you try to work it a little further ? few proposals ?
All in all again, you are definitly on the right track this is what we had in mind.