By Now you must realize that there is a lot involved in progressing to Expert, let alone being able to win a "Big" contest.
It depends a lot on individual talent and desire, but also on the kind of help available to you.
I have seen several individuals with a lot of talent progress from Beginner to Expert in as little as two years.
The two that I helped had the advantage of well trimmed Hand-Me-Down airplanes and the financial resources to crash an airplane and immediately get another one to fly. Also they both did not mess with inferior equipment but started with 1st class engines and well built airplanes.
Yes they did learn to build and fly their own airplanes and at least one became a good builder and finisher, but they used purchased equipment to keep flying and practiced a lot.
Living in Arizona or some other climate where it's possible to fly year round is also a big help in progressing quickly. Both of these folks quit flying before progressing to the top of any heap. Burnout? Maybe!
Now to the question of progressing to where it's possible to win a "Big Contest"; that's another matter.
There are a bunch of guys around with "Super Talent" and the resources to be really serious about flying the "Big Contests" and the simple truth is that most of the "experts" in the world will never beat those guys in an even contest. I fly with a couple of those kind of guys here in Tucson and while I can on occasion fly a pattern as good as thiers...they do it very consistently and seldom fly less than a stellar performance...even in practice.
The likes of Paul Walker, David Fitzgerald, Brett Buck, Bob Hunt, Bob Whitely, Derek Berry, Doug Moon, Orestes Hernandez, Bill Rich, Bill Werwedge, Ted Fancher, etc., will seldom, if ever, be outflown by one of us mere mortals. So...if you're talking about progressing to that level all I can say is best of luck, and fly, fly, fly, and get a really good coach that you can trust explicitly.
Me I gave up any hope of being in that level and I've been a mid pack Expert for about 40 years, who has won a few local Expert level contests in the distant past, but do not have the desire to beat my head against the brick wall of talent anymore.
It's still fun to fly with the likes of those folks and measure small improvements in myself without the inate ability to ever beat them.

The simple reality is that most of us will never get to the top of the expert heap...guess that's why it's desirable to try!

Randy Cuberly
