In this event, you can use any engine up to .1999. At The Brodak, this is further limited to side exhaust only, but The NCLRA lets you use any engine of that size.
You are limited to only one ounce of fuel. This makes it interesting, since a very fast gas hog engine will make more pit stops than a slower, more economical one. There are countless old .15's around, put out of business by F2d rules changes, as well as engines intended for RC quarter midget, Goodyear, vol libre, and other other events. There is little need to actually buy a new engine.
The NCLRA allows on Flying Clowns. Brodak also allows the Circus Prince, which has the same wing and a more stylish fuselage. NCLRA wants two wheels, Brodak lets you use one or two. Any normal builder should be able to knock out a couple of these littel beauties in under two weeks. See you in May.
The standard fuel is a key element. In any "mileage race", some people would run funny fuel with dangerous addatives that extend run time while damaging engines and often the people who handle the stuff. If anybody seriously intends to use a Diesel, contact me in advance. I will obtain a jug of factory-selled fuel from the Prop Shop. No funny fuel for you either !
2007 winners at both the Brodak and the Nats did about 170 laps in seven-an-a-half minutes and 290 laps in 15 minutes.