Kolb Firefly I
I put 14 hours on this airplane and made 100 landings. The Firefly was a FAR 103 legal ultralight that was powered by the heavier 40 hp Rotax 447 engine. The design features a forward fuselage of welded 4130 steel tubing, mated to an aluminum tailboom.
The horizontal stabilizer, tail fin and wings are also constructed of riveted aluminum tubing with all flying surfaces covered in doped aircraft fabric. The wings are quick-folding for storage and ground transport.