MD Helicopters 369-500, Maintenance Instructions Manual

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CSP-HMI-3
MD Helicopters, Inc
.
MAINTENANCE MANUAL
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[ Chapter 97 TOC ]
Page 902
Revision 12
97-08-00
The information disclosed herein is proprietary to MD Helicopters, Inc.
Neither this document nor any part hereof may be reproduced or transferred to
other documents or used or disclosed to others for manufacturing or any other
purpose except as specifically authorized in writing by MD Helicopters, Inc.
Copyright
©
1999 − 2016 by MD Helicopters, Inc.
NOTE:
D
After drilling or cutting operations, re­
move burrs and metal particles. Apply a
thin coat of primer (CM318) when install­
ing rivets or to bare metal areas, except
when hole is to be used for electrical
ground or bonding purposes. Color
matched paint may be applied over zinc
chromate primed areas.
D
When providing ground for electrical com­
ponents or for electrical bonding pur­
poses, clean designated structure areas to
bare metal surface (Ref. Chap. 96).
D
Do not tighten electrical clamps or secure
electrical wiring to existing harnesses un­
til all electrical wiring is installed.
E. Amplifier Assembly
(Ref. Figure 901, view A-A) The following
defines a procedure for reinforcing the elec­
tronics equipment floor structure, and for
installing the amplifier assembly.
(1). Using drill motor and appropriate drill
bit, remove rivets securing existing two
nutplates to existing support channel
installed on electronics compartment
floor.
(2). Drill and enlarge existing holes in
support channel to 0.257 in. (6.5278
mm) holes. Install rivnuts in support
channel using rivnut header.
(3). Drill and enlarge two existing holes in
new support channel to 0.240 in. (6.096
mm) holes for installation of nutplates.
Using nutplates as templates, drill four
0.098 in. (2.4892 mm) plates to support
channel with rivets.
(4). Using support channel as template,
drill 0.098 in. (2.4892 mm) rivet attach
holes in electronics compartment floor,
frame structure at Sta. 50.50, and
Cant. Sta. 64.365. Attach support
channel to electronics compartment
with rivets (Ref. Figure 901, view B).
NOTE:
When installing support hardware for
amplifier, provide ground by cleaning con­
tact surfaces of compartment floor, hard­
ware, and amplifier to bare metal.
(5). Using screws and washers, attach
forward and aft supports to support
channel and existing channel.
(6). Using screws, washers, and nuts,
attach channel assembly to forward
and aft supports.
(7). Using screws and washers, attach
supports to channel assembly.
NOTE:
Nutplates are provided to secure screws
on channel assembly.
(8). Using washer and existing amplifier
bolts, attach amplifier to supports on
channel assembly.
NOTE:
Electrical wiring at amplifier is not in­
stalled at this time.
F. Loudspeaker Assembly
(Ref. Figure 201) The following defines a
procedure for installing the loudspeaker and
support brackets on the helicopter, including a
doubler on the cutout in the fuselage skin just
forward and below the right side pilot's
compartment door.
(1). Using doubler as template, determine
six rivet hole locations required through
fuselage skin. Drill 0.098 in. (2.4892
mm) rivet holes and attach doubler to
fuselage skin with rivets.
(2). Install grommet in fuselage skin
cutout, as required.
(3). Verify that loudspeakers are installed
on mounting bracket, and that support
bracket is disconnected from mounting
bracket.
NOTE:
D
To facilitate installation of brackets make
certain that support bracket is discon­
nected from mounting bracket.
D
Nipples used for protection of terminals at
loudspeaker units may be stowed on wire
harness or provided as loose equipment.
(4). Position support bracket on outer
fuselage skin, at right longeron (WL
15.75) and bulkhead (Sta. 64.65), and
determine rivet hole locations for
support bracket. Drill 0.098 in. (2.4892
mm) rivet attach holes in support
bracket, and remove existing three