C/G And Balancing - Model Tech Sukhoi SU-31 Assembly Instructions Manual

IMPORTANT Make sure that the notch you cut in the side of the hatch cover does not pinch the servo leads.
Step 4: applYinG the deCalS
❑ Using a clean cloth, wipe the airframe down completely to remove dust, debris and oil.
❑ Working with one decal at a time, carefully cut out the decal along its outer edges.
❑ Remove the protective backing from the decal and stick the decal to the airplane. (Use the box cover photos to position the decals.)
Lightly rub the decal with a soft cloth to remove any trapped air from beneath it.
PRO TIP If any air bubbles form under the decal you can "prick" the bubbles with a straight pin to release the air.
❑ Repeat the procedures above to install the remaining decals. Rub each decal down thoroughly to adhere it into place.
IMPORTANT It is critical that your airplane be balanced correctly. At best, improper balance will make the airplane very difficult
to control. At worst, improper balance can cause your airplane to lose control and crash!
BALANCE POINT FOR TEST FLYING ANd SPORT FLYING:
4-1/4" (108mm) back from the leading edge of the wing, measured at the fuselage sides.
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BALANCE POINT FOR 3d FLYING:
5-1/8" (130mm) back from the leading edge of the wing, measured at the fuselage sides.
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WarnIng We strongly recommend starting out using the Test Flying and Sport Flying balance point until you are completely
familiar with the airplane's flight characteristics.
❑ Turn the airplane upside down, place your fingers on the wing at the balance point, and carefully lift the airplane. If the nose of
the airplane drops, the airplane is nose heavy. To correct this, move the battery pack and/or receiver back far enough to bring the
airplane into balance. If the tail of the airplane drops, the airplane is tail heavy. To correct this, move the battery pack and/or receiver
forward far enough to bring the airplane into balance. Because of the limited space to move the receiver and/or battery fore and aft,
you may also need to add weight to the tail or the nose to balance the airplane. When balanced correctly, the airplane should sit level
or slightly nose down when you lift it up with your fingers at the C/G location.
IMPORTANT Balance the airplane with the fuel tank empty.
❑ Set the hatch cover into place, then drill 1/16" (1.6mm) diameter pilot holes
through the wing, using the predrilled holes in the hatch cover as a guide.
❑ Secure the hatch cover to the wing, using four M2 x 10mm flange-head
wood screws.

C/G and BalanCinG

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