WAM used to have both endurance and economy events, and further subdivided by engine classes and skill class. Endurance had 12 separate trophies awarded, Economy 12, etc, or at least as well as I can remember. And they did this at *every contest*, more-or-less every other week during the summer.
Timing these events was torturous, of course, and with typical flights times of several hours, it took an amazing amount of space (since every other event in the rule book had to go, too). A typical B Economy plane was a Flite Streak with a McCoy 29 (red-head or blue-head) rigged with a TD 049 or Holland Hornet venturi, and and a 2 foot long 1/4" ID muffler extension.
They also had "cargo", think a holland hornet with maybe a 80" span 20:1 aspect ratio wing lifting maybe 10 lbs.
These type of events were the first to fall off or get dropped out when the site didn't permit it (which they apologized for my calling it a "limited" contest), and as events were dropped or not held, Stunt, Carrier, Sport Race , and Balloon Bust were the last holdouts.
Brett