Carf-Models Ultra Lightning Instruction Manual page 29

Important note for UL-Customers:
Please, before you fly, take note of this important information:
Please reinforce the carbon tube which connects the rudder fin to the fuselage. We
did have a failure in flight recently. It seems when you snap the plane violently, this
tube can break. Please slide in another tube, 12mm OD, into the exiting tube and
glue with CA Glue. If you have a carbon rod 12 mm you can use this, too. Even a
hard wood dowel will do the job, when you glue this into the tube with resin.
The CG is 15 mm behind the front edge of the gear door. If you want, you can start
with a CG slightly forward, and then move it slowly back to the point in the photo. The
UL is not very sensitive at all on the CG. (see attached picture)
Throws are pretty much the same then on the classic lightning. For flap deployment,
take-off position is 10-15mm flaps down, for landing, about 45 degrees.
You will need some down elevator mixing when flaps are deployed.
CG Position: