I am rather new to mine as and I understand the N3 Pup, Fischer 202, and Sparrow families are generally similar. I'm sure more exist.
Within Sparrow family, the original Sparrow is the ultralight. It typically flies on the power of something like Rotax 377. I think the biggest you can stuff into it is 503. It's the lightest member of the family and goes like a rocket on 40p 2-stroke.
Sparrow II is a two-seater, side-by-side, developed off the ultralight. It usually is equipped with a Rotax 582 and has gross takeoff weight of up to 1100 pounds. Note that an all-metal Sonex weighs about the same, but with a 80 hp VW engine. It's the wages of scaling up an ultralight design.
Sparrow II XTC addresses the problems of Sparrow II by using a Continental A-85. Some builders even put O-200 on it. I still think it's basically overweight.
Sparrow SS revisits the ultralight but uses lots of parts of Sparrow II, so it can use more powerful engines. Mine has an HKS 700E 4-stroke engine, notionally of 60 hp. Unfortunately, with all the goodies like BRS chute, radio, and long range tanks it is very heavy: about 2x the weight of the original Sparrow. The takeoff roll is about 800 ft and it can still land in some 600 ft and elevation of 4800 ft, but the problem is that the 60 hp power is only available for 1 minute. Once I trottle back to cruise climb, the turns into a sled with my 230 lbs onboard.
BTW, there's a thread about Sparrow SS for sale:
http://www.homebuiltairplanes.com/forum ... arrow.htmlIt looks very sharp and flies on the power of a 1/2 VW engine. Also has flaps, which mine doesn't have.
I'm thinking about bringing my Sparrow to some BCP fly-ins this summer, somewhere in Colorado most likely.