ELEVATOR BALANCING
1. Balancing Requirement
A. The elevator must be complete with these components installed before you do the balancing procedure.
(1) Elevator horn, bolts and nuts.
(2) Trim tab and pushrods.
(3) Static discharger wicks.
(4) Inboard rib closeout cap.
(5) Exterior paint.
B. Balancing elevators
(1) The elevator assembly must be complete as defined in Balancing Requirement, paragraph A, and the bonding
jumpers must be installed.
(2) Static balance limits: +7.0 inch-pounds (0.79 N.m) underbalance to +11.0 inch-pounds (1.24 N.m) underbalance.
C. Adjustable Balance Weight Limits (including trim weight retaining plate and attaching hardware.)
(1) Maximum certified adjustable balance weight 1.80 pounds (8.0 N).
D. Maximum Certified Elevator Weight.
(1) Maximum certified elevator weight is 36.80 pounds (163.7 N).
2. Elevator Balancing
A. Procedure.
(1) Install bolts in the inboard and outboard hinges (Refer to Figure 201).
(2) Hold the trim tab on the left and right elevators in a streamline position with a minimum amount of masking tape, and
install associated hardware (Refer to Figure 201).
NOTE: Make sure the elevator has freedom of movement, does not drag on the mandrels and that the
bonding straps are free.
(3) Put the elevator on mandrels so the knife blade mates with the torque tube and the outboard hinge.
(4) Balance the balancing beam. Refer to Control Surface Balancing, Figure 1.
(5) Attach the balancing beam to the elevator. Hook the hanger on the trailing edge as shown.
(6) If the elevator takes a position parallel with the base of the mandrel and the balance weight is between +7.0 to +11.0
inch-pounds (0.79 to 1.24 N.m), the elevator is statistically balanced.
(7) If the elevator takes a position of trailing edge up when balance weight is between +7.0 to +11.0 inch-pounds (0.79 to
1.24 N.m), the elevator is overbalanced and needs weight removed.
(a) Remove trim weights as necessary.
(8) If the elevator takes a position of trailing edge down when the balance weight is between +7.0 to +11.0 inch-pounds
(0.79 to 1.24 N.m), the elevator is underbalanced and needs additional balance weight.
(a) Drill out the fasteners that hold the rib closeout cap to the inboard rib.
(b) Add trim weights as necessary at the inboard rib.
(9) After the elevator is balanced, install the inboard rib closeout cap with S2907-4-2 blind rivets.
To Next Page
Loading...
Need help?
General
