TM 1-1520-238-23
11-992
Change 6
11.232.
DIRECTIONAL CONTROL SYSTEM INSPECTION – continued
NOTE
New swashplate bearings, have a tendency to purge grease in the initial hours of operation until the
grease is evenly distributed within the bearing. This purging can also be the result of operations in high
temperatures.
(3) The following procedure is to be used for assessing grease purging from the 7-311527038-15, -17, -19,
and -901 tail rotor swashplates.
(a) A small amount of grease purging from the swashplate is normal on new swashplate bearings for the
first 50 flight hours.
(b) After accrual of 50 flight hours, no excessive grease leakage is permitted except for an occassional
light trace; significantly less than a new, zero time bearing.
(c) If after the initial 50 flight hour period, grease is expelled in significant quantities (evidence on
surrounding components), remove and replace the tail rotor swashplate. Replace the swashplate
assembly (para 11.262).
b. Inspect tail rotor swashplate prior to removal for noisy or ratchety condition.
(1) Tail rotor blade inspection.
(a) Perform inspection of tail rotor blade bearings for pitch change force (para 5.51).
(2) Non-rotating swashplate inboard and outboard sleeve bearing inspection.
(a) Perform sleeve bearing inspection (para 11.232.4).
c. If these inspections are acceptable, reattach non-rotating swashplate to the bellcrank (para 11.262) and
pitch control links to pitch horn (para 5.54).
CAUTION
To avoid damage to clevis and bellcrank, do not allow swashplate assembly to creep inboard and
contact the bellcrank while rotating swashplate.
11.232.5. -15, -17, -19, and -901 Swashplate Inspection Procedure Prior to Installation
a. Remove tail rotor de-ice brush block from tail rotor swashplate (para 11.262).
b. Rotate the swashplate with a firm and constant rotational motion in one direction (preferably the
direction of blade rotation) a minimum of six full 360 degree rotations.
(1) Initially the bearing may exhibit a roughness and/or a ratchety feeling along with some apparent binding.
GO TO NEXT PAGE
