TM 1-1520-253-23
6.2.1 Description (Figure 6-1. Index No. 9). Control inputs from the cockpit are transmitted through adjustable and
nonadjustable mechanical linkage to the Integrated Lower Control Actuator (ILCA). The ILCA then transmits individual
control motions to the first and second stage mixing units. The mixed outputs are then transmitted through a series of
push-pull tubes to the upper dual-boost actuators attached to the forward and aft swashplates.
6.2.2 Defects. This inspection is to verify cracks found visually. No cracks are allowed.
6.2.3 Primary Method. Eddy Current.
a. Eddy Current Inspection Unit b.
b. Probe, straight, shielded surface, 100 KHz-500 KHz
c. Probe, right angle, shielded surface, 100 KHz-500 KHz, 901/2 inch drop
d. Cable Assembly
e. Reference Block, three-notched aluminum (0. 008, 0. 020, and 0. 040 EDM notches)
f.
6.2.3.2 Preparation of Helicopter. The helicopter shall be prepared for safe ground maintenance. If required, the
connecting links shall be removed in accordance with the applicable technical manuals listed in Table 1-1.
6.2.3.3 Access. Access is obtained through transmission work platforms, flight controls closet panel, or cockpit. See
6.2.3 4 Preparation of Part. The connecting link shall be thoroughly cleaned. Refer to Preparation of Part or Area for
NDI, paragraph 1.4.4.
6.2.3.5 NDI Equipment Settings.
II
a.
Make the following initial settings on the Eddy Current Inspection Unit, NORTEC-19e .
Frequency F1
- 200 KHz
F2
- off
HdB
- 57.0
VdB
- 69.0
Rot
- 56
Probe drive
- mid
LPF
- 100
HPF
-0
H Pos
- 80%
V Pos
-20%
6-3
