AM.II.C.S11

From the FAA library

• Aviation Maintenance Technician Handbook - Airframep. 2-36
  Chapter 2: Aerodynamics, Aircraft Assembly, & Rigging › Rebalancing of Control Surfaces › Static Balance

  control surface may be out of static balance. They are called underbalance and overbalance. When a control surface is mounted on a balance stand, a downward travel of the trailing edge below the horizontal position indicates underbalance. Some manufacturers indicate ... sign. These signs show the need for more or less weight in the correct area to achieve a balanced control surface, as shown in Figure 2-60. A tail-heavy condition (static underbalance) causes undesirable flight performance…

• Aviation Maintenance Technician Handbook - Airframep. 2-36
  Chapter 2: Aerodynamics, Aircraft Assembly, & Rigging › Airplane Assembly & Rigging › Rebalancing of Control Surfaces

  Rebalancing of Control Surfaces This section is presented for familiarization purposes only. Explicit instructions for the balancing of control surfaces are given in the manufacturer’s service and overhaul manuals for the specific aircraft and must be followed closely ... that could cause the complete loss of the aircraft. Rebalancing a control surface concerns both static and dynamic balance. A control surface that is statically balanced is also dynamically balanced…

• Aviation Maintenance Technician Handbook - Airframep. 2-36
  Chapter 2: Aerodynamics, Aircraft Assembly, & Rigging › Airplane Assembly & Rigging › Rebalancing Procedures

  location of the weights are, in most cases, forward of the hinge center line. Figure 2-60. Control surface static balance. Rebalancing Procedures Repairs to a control surface or its tabs generally increase the weight aft of the hinge center ... installing the control surface in the stand or jig, a neutral position should be established with the chord line of the surface in a horizontal position. Use a bubble protractor to determine the neutral position before continuing balancing procedures. [Figure…