Find the CG by weighing

What you need

• Three kitchen or postal scales
• A tape measure
• The model ready to fly, with the fuel tank empty

Steps

1. Open Bench, choose the aircraft, and tap CG by weighing.
2. Under Landing gear, choose Tricycle or Taildragger.
3. Put a scale under each wheel, with the model level and ready to fly.
4. Enter each wheel's weight.
5. Measure each wheel's distance from the wing's leading edge at the root, along the fuselage. Wheels ahead of it are negative.
6. Read the CG. To move it, enter where nose or tail weight would go, and see how much to add.
7. Tap the Save button.

Good to know

• Zero each scale before the model goes on it.
• Weigh glow and gas models with the fuel tank empty.
• Nose weight positions are usually negative, because they're ahead of the leading edge.

Words used here

CG

Center of gravity: the point where the model balances. Too far back makes it unstable. Too far forward makes the nose hard to lift.

Leading edge

The front edge of a wing, stab or control surface.

Root

The inner end of a wing or stab, where it meets the fuselage.

Related guides

• Level the model on a balancerUse the iPhone as a level while the model rests on a CG balancer.
• Work out where the CG should beEnter or measure the wing's size to find the range where the model should balance.