TECHNICAL BULLETIN xxx-xx-xxx

TECHNICAL BULLETIN
429-12-23
22 October 2013
MODEL AFFECTED:
429
SUBJECT:
WEATHER RADAR KIT RETROFIT AND TCAS
ANTENNA KIT RETROFIT, INTRODUCTION OF.
HELICOPTERS AFFECTED:
Serial number 57001 and subsequent with
429-706-018-101 Weather Radar Kit installed.
COMPLIANCE:
At customer’s option.
DESCRIPTION:
This bulletin introduces a more streamlined weather radome assembly and relocation
of the TCAS antenna if installed. Applicability of this bulletin to any spare part shall be
determined prior to its installation on an affected helicopter.
APPROVAL:
The engineering design aspects of this bulletin are Transport Canada Civil Aviation
(TCCA) approved.
CONTACT INFO:
For any questions regarding this bulletin, please contact:
Bell Helicopter Product Support Engineering - Intermediate Helicopters
Tel: 450-437-2077 / 1-800-463-3036 / [email protected]
MANPOWER:
Approximately 50 man-hours are required to complete this bulletin. This estimate is
based on hands-on time, and may vary with personnel and facilities available.
WARRANTY:
There is no warranty credit applicable for parts or labor associated with this bulletin.
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ECCN EAR99
MATERIAL:
Required Material:
The following material is required for the accomplishment of this bulletin and may be
obtained through your Bell Helicopter Textron Supply Center.
Part Number
429-704-007-101
429-704-006-101
MS25036-152
S200-2-W1-22-9
M39029/57-354
Nomenclature
TCAS Antenna Retrofit Kit
Weather Radar Retrofit Kit
Terminal Lug
Shield Termination
Contact
Qty
1
1
2
6
25
Consumable Material:
The following material is required to accomplish this bulletin, but may not require
ordering, depending on the operator’s consumable material stock levels. This material
may be obtained through your Bell Helicopter Textron Supply Center.
Part Number
Nomenclature
Qty
Reference *
MIL-PRF-81733 TYII
Magnobond 6398 50
GM
EA9309NA
MIL-C-81706 1 QT
MIL-C-81706,CL3PWDR
MIL-PRF-23377, TY I
PRIMR KT
CA1000
Sealant
Adhesive
1
1
C-251
C-317
Adhesive
Alodine
Iridite 14-2
Epoxy Polyamide Primer
Corrosion Preventive
Compound
Adhesive
1
1
1
1
C-331
C-100
C-099
C-204
1
C-586
1
C-300
299-947-152TYICL1 QT
* C-XXX numbers refer to the consumables list in BHT-ALL-SPM Standard Practices Manual
SPECIAL TOOLS:
Part Number
M81969/14-01
M22520/2-01 or M22520/7-01
M22520/2-06 or M22520/7-06
Nomenclature
Insertion/Extraction Tool
Crimping Tool
Turret or Positioner
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ECCN EAR99
Quantity
1
1
1
WEIGHT AND BALANCE:
Longitudinal
Moment
+212 in-Lbs
+2445 kg x
1925 mm
mm/100
Weight
Arm
75.8 in.
+2.8 Lbs
+1.3 kgs
Arm
0.0 in.
Lateral*
Moment
0.0 in-Lbs
0.0 mm
0.0 kg x mm/100
* In lateral calculations, - is left and + is right.
ELECTRICAL LOAD DATA:
Not affected.
REFERENCES:
BHT-429-IPB Illustrated Parts Breakdown
BHT-429-MM Maintenance Manual
BHT-ALL-SPM Standard Practice Manual
PUBLICATIONS AFFECTED:
BHT-429-MM Maintenance Manual
BHT-429-IPB Illustrated Parts Breakdown
-NOTEWeather Radar Retrofit Kit 429-704-006-101
compatible with Ditching Kit 429-706-048-101.
is
not
ACCOMPLISHMENT INSTRUCTIONS:
1. Prepare helicopter for maintenance.
a. Remove the existing radome assembly 429-030-039-101. (BHT-429-MM,
Chapter 52).
b. Remove the lower TCAS antenna P/N S72-1750-32L if installed. (BHT-429-MM,
Chapter 97).
c. Remove the weather radar receiver transmitter antenna. (BHT-429-MM,
Chapter 97).
d. Remove the battery access door 429-030-114-101. Retain the NAS5314E3P8
screws and MS21042L3 nuts. Discard the NAS1149E0332P washers.
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e. Remove the left and right hand chin bubbles 429-330-146-101/-102. (BHT-429MM, Chapter 52).
f. Remove the landing light panel 429-030-164-101. (BHT-429-MM, Chapter 52).
g. If the Cabin Air Conditioning System Kit is installed, refer to the Air Comm
Corporation (STC # SR00693DE) for the depressurization of the system and
the removal of the forward left and/or right side evaporators, as applicable.
-NOTEIf the left hand bracket 429-030-138-101 and right hand
bracket 429-030-138-103 already have the receptacles and
nutplates installed, continue to step 6.
2. Prepare the left hand bracket 429-030-138-101 (1, Figure 1) as follows:
a. Locate and drill one hole 0.473 to 0.478 inch (12.01 to 12.14 mm) in diameter
through the left bracket (1) with a 15/32 drill to the dimension shown in Detail C.
b. Locate and drill two holes 0.232 to 0.237 inch (5.89 to 6.01 mm) in diameter
through the left bracket (1) with a 15/64 drill to the dimension shown in Detail C.
-NOTEUse the receptacle (5) as a template to locate the holes for
the rivets (4) on the left bracket (1).
c. Put the receptacle (5) in position on the left bracket (1) and drill two holes
0.1285 inch (3.26 mm) in diameter through the left bracket (1) with a No. 30 drill
as shown in Detail B.
-NOTEUse the nutplates (2) as a template to locate the holes for
the rivets (3) on the left bracket (1).
d. Put the nutplates (2) in position on the left bracket (1) and drill four holes 0.098
inch (2.49 mm) in diameter through the left bracket with a No. 40 drill.
e. Countersink the six rivet holes 100° on the far side of the left bracket (1).
f. Deburr all holes.
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ECCN EAR99
g. Install the receptacle (5) on the left bracket (1) with two rivets (4) (BHT-ALLSRM, Chapter 3).
h. Install each nutplate (2) on the left bracket (1) with two rivets (3) (BHT-ALLSRM, Chapter 3).
3. Prepare the right bracket 429-030-138-103 (8) as follows:
a. Locate and drill one hole 0.473 to 0.478 inch (12.01 to 12.14 mm) in diameter
through the right bracket (8) with a 15/32 drill to the dimension shown in Detail
E.
b. Locate and drill two holes 0.232 to 0.237 inch (5.89 to 6.01 mm) in diameter
through the right bracket (8) with a 15/64 drill to the dimension shown in Detail
E.
-NOTEUse the receptacle (7) as a template to locate the holes for
the rivets (10) on the right bracket (8).
c. Put the receptacle (7) in position on the right bracket (8) and drill two holes
0.1285 inch (3.26 mm) in diameter through the right bracket with a No. 30 drill
as shown in Detail D.
-NOTEUse the nutplates (6) as a template to locate the holes for
the rivets (9) on the right bracket (8).
d. Put the nutplates (6) in position on the right bracket (8) and drill four holes 0.098
inch (2.49 mm) in diameter through the right bracket with a No. 40 drill as
shown in Detail D.
e. Countersink the six holes 100° on the far side of the right bracket (8).
f. Deburr all holes.
g. Install the receptacle (7) on the right bracket (8) with the rivets (10) (BHT-ALLSRM, Chapter 3).
h. Install each nutplate (6) on the right bracket (8) with two rivets (9) (BHT-ALLSRM, Chapter 3).
4. Locate and drill one hole 0.203 to 0.208 inch (5.16 to 5.28 mm) in diameter through
the left bracket (1) with a No. 5 drill to the dimension as shown in Detail C.
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ECCN EAR99
5. Locate and drill one hole 0.203 to 0.208 inch (5.16 to 5.28 mm) in diameter through
the right bracket (8) with a No. 5 drill to the dimension as shown in Detail E.
6. Put the left and right brackets (1 and 8) in position on the landing light cover panel
(100F) (15) as shown in Detail F and secure with Cleco fasteners.
7. On the left bracket (1), backdrill one hole 0.203 to0.208 inch (5.16 to 5.28 mm) in
diameter from the landing light cover panel (100F) (15) through the left bracket with
a No. 5 drill as shown in Detail C.
8. On the right bracket (8), backdrill one hole 0.203to 0.208 inch (5.16 to 5.28 mm) in
diameter from the landing light cover panel (100F) (15) as shown in Detail F
through the right bracket with a No. 5 drill as shown in Detail E.
9. Locate and drill four holes 0.098 inch (2.49 mm) in diameter through the left and
right brackets (1 and 8) and the landing light cover panel (100F) (15) as shown in
Detail F with a No. 40 drill, to the dimension as shown in Detail C and Detail E.
10. Remove the left and right brackets (1 and 8) from the landing light cover panel
(100F) (15) as shown in Detail F.
11. Countersink the four 0.098-inch holes 100° on the far side of landing light cover
panel (100F) (15).
12. Deburr all holes.
13. Temporarily install the left and right brackets (1and 8) and the landing light cover
panel (100F) (15) on the helicopter with eight screws. Tighten the screws.
14. If installed, remove the seal (28, Section G-G) from the aft edge of the forward
radome (23).
15. Temporarily install the forward radome (23) on the forward nose bulkhead
assembly (21). Tighten the fasteners.
-NOTEThe following step is to make sure that the brackets will not
move.
16. Secure the left and right brackets (1 and 8) to the inside surface of the forward
radome (23) with tape.
17. Mark the center of the nutplate holes on the left and right brackets (1 and 8) and on
the forward radome (23) with a non-permanent marker.
18. Mark the location of the four 0.203 to 0.208-inch holes on the aft radome (27) with
a non-permanent marker to the dimension shown in Section G-G.
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ECCN EAR99
19. Put the aft radome (27) in position on the left and right brackets (1 and 8) and the
left and right panel assemblies (24 and 26). Secure in place with tape.
20. Make sure the aft radome (27) is correctly positioned and a constant gap exists.
Dimension shown in Section G-G.
21. Transfer the mark previously made from the forward radome (23) to the aft radome
(27) to mark the center of the four 0.203 to 0.208-inch holes to the dimension
shown in Section G-G.
22. Remove the tape.
23. Remove the aft radome (27) from the left and right panel assemblies (24 and 26).
24. Drill four holes 0.203 to 0.208 inch (5.16 to 5.28 mm) in diameter through the aft
radome (27) with a No. 5 drill, as shown in Section G-G. Deburr all holes.
25. Temporarily install the aft radome (27) on the left and right panel assemblies (24
and 26) and the left and right brackets (1 and 8) with four screws (25).
26. Tighten the screws.
27. Secure the aft radome (27) on the left and right panel assemblies (24 and 26) with
tape.
28. Locate and drill eight holes 0.098 inch (2.49 mm) in diameter from the aft radome
(27) through the left and right panel assemblies (24 and 26) with a No.40 drill.
29. Open eight holes 0.193 to 0.198 inch (4.90 to 5.03 mm) in diameter, through the aft
radome (27) and the left and right panel assemblies (24 and 26) with a No. 10 drill.
30. Remove the screws (25) and the aft radome (27) from the left and right panel
assemblies (24 and 26). Retain the screws. Deburr all holes.
31. Remove the forward radome (23).
32. Open seven holes 0.203 to 0.208 inch (5.16 to5.28 mm) in diameter, through the
aft radome (27) with a No. 5 drill, as shown in Section G-G. Deburr all holes.
33. Open one hole 0.249 to 0.255 inch (6.32 to6.48 mm) in diameter, through the aft
radome (27) with a 1/4 inch drill, as shown in Section G-G. Deburr all holes.
34. . Install four inserts (29) on the left panel assembly (24) as follows:
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ECCN EAR99
-NOTEDo not drill through the outer skin of the left panel assembly
(24). Use a shortened drill bit.
a. Open four holes 0.386 to 0.392 inch (9.80to 9.96 mm) in diameter, through the
inner skin plies only of the left panel assembly (24) as shown in Section I-I.
b. Undercut core 0.80 inch (20.3 mm) in the left panel assembly (24) as shown in
Section I-I (BHT-ALL-SRM, Chapter 4).
c. If required, do the shimming of each insert (29) as follows:
(1) Put each insert (29) in position in the 0.386 to 0.392-inch hole of the left
panel assembly (24).
(2) Measure the gap between the head of each insert (29) and the inner skin of
the left panel assembly (24) as shown in Section I-I.
-NOTEEach one of the laminated shims (32) is 0.016 inch (0.41
mm) thick and each lamination is 0.002 inch (0.05 mm) thick.
Install a maximum of three laminated shims per insert (29) to
fill the gap.
(3) Peel the laminated shim (32) as required to fill the gap between the head of
the insert (29) and the left panel assembly (24).
d. Install each of the four inserts (29) and, if applicable, the laminated shim(s) (32)
on the left panel assembly (24) with adhesive (C-317) per the instructions for
dome head type potted inserts, Application C, contained in the BHT-ALL-SRM,
Chapter 3.
35. . Install two inserts (31) on the right panel assembly (26) as follows:
a. Open two holes 0.386 to 0.392 inch (9.80 to9.96 mm) in diameter through the
inner skin plies only of the right panel assembly (26) as shown in Section I- I.
b. Undercut core 0.80 inch (20.3 mm) in the right panel assembly (26) as shown in
Section I-I (BHT-ALL-SRM, Chapter 4).
c. If required, do the shimming of each insert (31) as follows:
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ECCN EAR99
(1) Put each insert (31) in position in the 0.386 to 0.392-inch hole of the right
panel assembly (26).
(2) Measure the gap between the head of each insert (31) and the inner skin of
the right panel assembly (26) as shown in Section I-I.
-NOTEEach one of the laminated shims (32) is 0.016 inch (0.41
mm) thick and each lamination is 0.002 inch (0.05 mm) thick.
You can install a maximum of three laminated shims per
insert (29) to fill the gap.
(3) Peel the laminated shim (32) as required to fill the gap between the heads of
the inserts (31) and the left panel assembly (26).
d. Install each of the two inserts (31) and, if applicable, the laminated shim(s) (32)
on the right panel assembly (26) with adhesive (C-317) per the instructions for
dome head type potted inserts, Application C, contained in the BHT-ALL-SRM,
Chapter 3.
36. Install the radius block (35) Section H-H on the right panel assembly (26) as
follows:
a. Draw a line to mark the center of the radius block (35) longitudinally with a nonpermanent marker.
b. Put the radius block (35) in position on the inner skin. Trim as required, to fit
the contour of the right panel assembly (26) and to clear the pitot flange rivet,
as shown in Section J-J.
c. Put the radius block (35) in position on the right panel assembly (26) and align
the previously drawn line with the center of the existing hole in the right panel
assembly. Secure in place with tape.
d. Backdrill one hole 0.193 to 0.198 inch (4.90to 5.03 mm) in diameter from the
right panel assembly (26) through the radius block (35) with a No. 10 drill.
e. Backdrill one hole 0.249 to 0.255 inch (6.32to 6.48 mm) in diameter from the
right panel assembly (26) through the radius block (35) with a ¼” drill.
f. Remove the radius block (35) from the right panel assembly (26).
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ECCN EAR99
-NOTEAs there is not enough access, use a shortened drill bit.
CAUTION
Do not drill through the outer skin of the right panel assembly
(26).
g. Open one hole 0.271 to 0.278 inch (6.88 to7.06 mm) in diameter through the
inner skin and core of the right panel assembly (26, Section J-J).
h. Open one hole 0.271 to 0.278 inch (6.88 to7.06 mm) in diameter through the
radius block (35).
i.
Countersink the hole at 100° in the radius block (35) on the far side to 0.510 to
0.515 inch (12.95to 13.08 mm), as shown in Section J-J.
j.
Deburr all holes.
k. At the hole 0.249 to 0.255-inch location, remove any trace of glue from the inner
surface of the outer skin of the right panel assembly (26) to make sure that the
end of the grommet (34) will sit properly.
l.
Fill the core edges of the right panel assembly (26) with adhesive (C-317) prior
to installing the grommet (34).
m. Install the radius block (35) on the right panel assembly (26) with adhesive (C317), as shown in Section J-J.
n. Install the grommet (34) on the right panel assembly (26) and the radius block
(35) with adhesive(C-317), as shown in Section J-J. Clean any excess
adhesive.
-NOTEAllow 24 hours for adhesive to cure at room temperature.
o. Install the nutplate (33) on the radius block (35) with adhesive (C-331), as
shown in Section J-J in accordance with the instructions contained in the BHTALL-SRM, Chapter 3, Application B for the bonded nutplate.
37. Install the nutplate (30) Section H-H on the left panel assembly (24) as follows:
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ECCN EAR99
a. Open one hole 0.193 to 0.198 inch (4.90 to 5.03 mm) to 0.232 to 0.237 inch
(5.89 to 6.02 mm) in diameter through the left panel assembly (24) with a 15/64
drill as shown in Section H-H.
b. Install the nutplate (30) on the left panel assembly (24) with adhesive (C-331),
as shown in Section H-H in accordance with the instructions contained in the
BHT-ALL-SRM, Chapter 3, Application B for the bonded nutplate.
38. Modify the landing light cover panel (100F) (15) View K as follows:
a. Remove the organic finish from the external surface of the landing light cover
panel (100F) (15) to the dimension shown in View K.
b. Prepare the faying surfaces of the left and right brackets (1 and 8) View F and
the landing light cover panel (100F) (15) for Class R-I electrical bonding
requirements (BHT-ELEC-SPM, Chapter 8).
c. Apply sealant (C-251) to the shanks of the rivets (14 and 20).
d. Install the left and right brackets (1 and 8) on the landing light cover panel
(100F) (15) with the rivets (14 and 20), respectively.
e. Verify that the electrical bonding between the left and right brackets (1 and 8)
and the landing light cover panel (100F) (15) meets Class R-1 requirements.
f. Seal the electrical bonding area around the left and right brackets (1 and 8) and
the landing light cover panel (100F) (15) with sealant (C-251).
g. Change the identification of the landing light cover panel (100F) (15) to landing
light cover panel (100F) (16) 429-530-027-107 with a permanent marker.
39. Modify the forward nose bulkhead assembly (21) as follows:
a. Remove and discard the two existing nutplates (11, View F) from the forward
nose bulkhead assembly (21).
b. Apply sealant (C-251) to the shanks of the rivets (13).
c. Install each of the two nutplates (12) with two rivets (13) on the forward nose
bulkhead assembly (21) (BHT-ALL-SRM, Chapter 3).
CAUTION
Do not exceed the maximum allowable temperature when
cutting a part or damage to the part may occur.
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ECCN EAR99
-NOTE-
Temperature label P/N TL-10-105-30 can be used to monitor
the temperature on the forward nose bulkhead assembly
(21).
d. Locate and mark the area of the forward nose bulkhead assembly (21) View L
with a permanent marker to the dimension shown in Section M-M and section
N-N.
e. Remove the sealing tape from the nose forward bulkhead assembly (21).
f. Cut the forward nose bulkhead assembly (21) to the dimension shown in
Section M-M and Section N-N but do not exceed the maximum temperature of
180°F (82°C).
g. Remove all sharp edges to have a radius of 0.005 to 0.015 inch (0.13 to 0.38
mm) or chamfer the edge 0.005 to 0.015 inch (0.13 to 0.38 mm) by 40 to 50° on
the forward nose bulkhead assembly (21).
h. Chamfer both corners on the forward nose bulkhead assembly (21) to 0.050
inch x 45° (12.7 mm x 45°), as shown in Section M-M.
i.
Apply chemical film material (C-100) to the trimmed area on the forward nose
bulkhead assembly (21) (BHT-ALL-SPM, Chapter 3).
j.
Apply two coats of epoxy polyamide primer (C-204) to the trimmed area on the
forward nose bulkhead assembly (21) (BHT-ALL-SPM, Chapter 4).
k. Change the identification of the forward nose bulkhead assembly (21) to the
forward nose bulkhead assembly (22) 429-530-027-103 with a permanent
marker.
l.
Locate and drill two holes 0.203 to 0.208 inch (5.16 to 5.28 mm) in diameter
through the forward nose bulkhead assembly (22) with a No. 5 drill to the
dimension shown in Section O-O.
40. Install the weather radar door assembly (2) Figure 2, Detail A and the washers
(11) in position on the clevis (8) and install the screws (5), washers (6), and nuts
(7). Tighten the nuts.
41. Install each of the two jumper assemblies (18) as shown in Detail C on the forward
nose bulkhead assembly (1) as follows:
a. Prepare the mating surfaces of the forward nose bulkhead assembly (1) and the
washers (15) for Class R-I electrical bonding requirements (BHT-ELEC-SPM,
Chapter 8).
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ECCN EAR99
b. At two locations, install the screw (14), washers (15), jumper assembly (18),
lockwasher (16), and nuts (17) on the forward nose bulkhead assembly (1).
Tighten the nuts.
c. Verify that the electrical bonding between the forward nose bulkhead assembly
(1) and the washers (15) meets Class R-I requirements (BHT-ELEC-SPM,
Chapter 8).
d. Seal the electrical bonding area with sealant (C-251).
42. Attach each of the two jumper assemblies (18) Detail B on the weather radar door
assembly (2) as follows:
a. Prepare the mating surfaces of the weather radar door assembly (2) and the
washers (21) for Class R-I electrical bonding requirements (BHT-ELEC-SPM,
Chapter 8).
b. Install the screws (19), lockwashers (20), washers (21), and nuts (22). Tighten
the nuts.
c. Verify that the electrical bonding between the weather radar door assembly (2)
and the washers (21) meets Class R-I requirements (BHT-ELEC-SPM, Chapter
8).
d. Seal the electrical bonding area with sealant (C-251).
e. Install the washers (21) jumper assemblies (18), lockwashers (20), and nut (23).
Tighten the nuts.
f. Close the weather radar door assembly (2).
g. Install the bolts (3) Detail A. and the washers (4) on the weather radar door
assembly (2). Tighten the bolts.
43. If the TCAS retrofit kit is to be installed on the helicopter at the same time, perform
the following steps:
a. Put the standoff (2) Figure 3 in position on the landing light cover panel (100F)
(1) and drill two holes 0.098 inch (2.49 mm) in diameter through the landing
light cover with a No. 40 drill as shown in View A.
b. Deburr all holes.
c. Install the standoff (2) on the landing light cover panel (1) with the rivets (3)
(BHT-ALL-SRM, Chapter 3).
d. Install grommet (4) on the landing light panel using adhesive (C-331).
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ECCN EAR99
e. Loosen the clamping for TCAS antenna coaxial cable and pull down sufficient
cable from the loop under the equipment shelf to reach the new antenna
location on the aft radome.
f. Remove and discard the TCAS antenna blanking plate cover and hardware
from the aft radome.
g. Install the TCAS antenna on the aft radome using original hardware.
h. Edge seal the TCAS antenna and overcoat the fasteners with sealant (C-251).
i.
Thread the TCAS antenna coaxial cable through the landing light cover panel
(1) and clamp to standoff (2) using clamps (5), washer (6), and screw (7) as
shown in View A.
44. Apply corrosion preventive compound (C-586) to the shanks of the screws (17 and
19) Figure 1, View F.
45. Apply corrosion preventive compound (C-586) to the edge of the mating surfaces
of the landing light cover panel (100F) (16).
46. Install the landing light cover panel (100F) (16) with the screws (17 and 19). Torque
the screws.
47. If previously removed, install the seal (28) on the aft edge of the forward radome
(23) with adhesive(C-300) (BHT-ALL-SPM, Chapter 7).
48. Install the aft radome as follows:
a. Apply sealant (C-251) to the faying surfaces of the grommet (9) (Figure 4,
Section B-B) and the aft radome (1).
b. Install the grommet (9) on the aft radome (1).
c. Temporarily install the tube (10) on the battery vent tube.
d. Temporarily put the aft radome (1) in position on the panel assemblies.
e. Install and adjust the length of the tube (10) to 0.9 inch (22 mm) from the
grommet (9), as shown in Section B-B.
f. Make sure the bevel of the tube (10) points aft.
g. Mark the length of the tube (10) with tape or a permanent pen.
h. Remove the aft radome (1) from the panel assemblies.
i.
Remove the tube (10) from the battery vent tube.
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ECCN EAR99
j.
Apply sealant (C-251) on the battery vent tube and on the internal surface of the
tube (10).
k. Install the tube (10) over the battery vent tube. Secure with a tie wrap (C-592).
l.
Prepare the mating surfaces of the left and right brackets (11 and 12) and the
shim areas of the aft radome (1) for Class R-I electrical bonding requirements
(BHT-ELEC-SPM, Chapter 8).
m. Apply corrosion preventive compound (C-586) to the shanks of the screws (2, 3,
4, 5, 6, and 7). Do not apply corrosion preventive compound to the threads.
n. Run the tube (10) through the grommet (9) and put the aft radome (1) in
position on the panel assemblies.
o. Install the screws (2, 3, 4, 5, and 6). Torque the screws.
p. Install the screws (7) with the washers (8) on the aft radome (1). Torque the
screws.
q. Verify that the tube (10) is 0.9 inch (22 mm) from the grommet (9), as shown in
Section B-B.
49. Install the forward radome (3, Figure1-14) on the forward nose bulkhead (5).
Tighten the fasteners.
-NOTEMetallic finishes are not permitted on the exterior surface of
the radome. The diverter strips are essential for flight and
must be installed on the forward radome prior to any flight
operation. The diverter strips are to be installed after final
coat of organic finish.
50. Install the forward radome diverter strips (1 Figure 5) as follows:
a. Locate the forward radome (3) center axis as follows:
(1) Locate the forward radome (3) center axis along the BL 0.0 of the helicopter.
(2) Mark the location of the four diverter strips (1) with tape to the dimension
shown in View A and View B.
b. Thoroughly wipe the surface of the forward radome (3) to receive the four
diverter strips (1) View A and View B with a clean cloth (C-516) moistened with
aliphatic naphtha (C-305) or isopropyl alcohol (C-285).
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c. Allow the surface to air dry for at least 30 minutes.
-NOTEEight diverter strips are provided with the kit. Keep extra
strips for future use if not needed.
d. Install the top two diverter strips (1, View A and Detail C) as follows:
(1) Peel back a portion of the liner from the adhesive backing of the diverter
strips (1, View A).
(2) The maximum allowable gap between the diverter strip (1) and the fastener
(2) is 0.010 inch (0.25 mm), as shown in Detail C.
(3) Position the edge of the diverter strip (1) as close to the fastener (2) as
possible.
(4) Press the peeled section to the receiving surface with firm finger pressure
and align the tip end of the diverter strips (1) to the dimension shown in View
A.
(5) Continue to peel the liner and apply finger pressure until the diverter strips
(1, View A) are securely applied.
e. Install the bottom two diverter strips (1, View B and Detail D) as follows:
(1) Peel back a portion of the liner from the adhesive backing of the diverter
strips (1, View B).
-NOTEThe maximum allowable gap between the diverter strip (1)
and fastener (2) is 0.010 inch (0.25 mm), as shown in Detail
D.
(2) Position the edge of the diverter strip (1, View B and Detail D) under the
ejection blade (4), as close to the fastener (2) as possible.
(3) Press the peeled section to the receiving surface with firm finger pressure
and align the tip end of the diverter strips (1) to the dimension shown in View
B.
(4) Continue to peel the liner and apply finger pressure until the diverter strip (1,
View B) is securely applied.
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51. Install weather radar receiver transmitter antenna. (BHT-429-MM, Chapter 97).
52. Assemble the required 429-079-530-111 wiring harness assembly as follows:
a. Disconnect the connector (3421P1) (4, Figure 6) of the cable (5) from the
receptacle (3421J1) (3) on the nose forward bulkhead assembly (1).
b. Disconnect the connector (3421TR1P1) (8) of the cable assembly (5) from the
WU-660 RCVR/XMIT/ANT (3421TR1) (2).
c. Remove the cable assembly (5). Retain the clamp (6) and the attaching
hardware.
d. Disassemble the backshell (14, Detail B) and the cover (15). Retain the three
existing screws (11).
e. Remove the two terminal lugs from the shield grounding stud (13) inside the
backshell (14). Retain the nut and the washers for reinstallation.
f. Using the extraction tool, disconnect the wires from the connector (3421TR1P1)
(8, Detail B).
g. Remove the cable assembly (5) from the backshell (14). Retain the backshell
and discard the cable assembly.
h. Locate the cable assembly (10, Detail A).
i.
Temporarily connect the connector (3421P1) (4) to the receptacle (3421J1) (3)
on the nose forward bulkhead assembly (1).
j.
Route the cable assembly (10) from the connector (3421P1) (4) to the location
of the receptacle (3421TR1J1) (9) under the WU-660 RCVR/XMIT/ANT
(3421TR1) (2).
k. Determine the required length for the cable assembly (10) to the receptacle
(3421TR1J1) (9). Trim the wires to length.
l.
Remove the cable assembly (10) from the receptacle (3421J1) (3).
m. If not already installed, install the identification (130-061-16W3) over the wires
of the cable assembly (10) within 6.0 inches (152 mm) of the connector
(3421TR1P1) (8).
n. Locate the wires S002A24, S003A24, S004A24, S005A24, S006A24, and
S006A24 in the cable assembly (429-079-530-111) (8, Figure 7).
o. Trim the jacket and the shield of the wires S002A24, S003A24, S004A24,
S005A24, S006A24, and S006A24 (BHT-ELEC-SPM, Chapter 4).
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p. Install one shield termination (2) over the trimmed shield end of each of the
wires S002A24, S003A24, and S004A24 (BHT-ELEC-SPM, Chapter 4).
q. Install one shield termination (2) over the trimmed shield end of each of the
wires S005A24, S006A24, and S006A24 (BHT-ELEC-SPM, Chapter 4).
r. Install one terminal lug (3) at the end of the shield termination lead of the wires
S002A24, S003A24, and S004A24 (BHT-ELEC-SPM, Chapter 4).
s. Install one terminal lug (3) at the end of the shield termination lead of the wires
S005A24, S006A24, and S006A24.
t. Install one contact (4) at the end of each of the wires in step 16 using the
crimping tool and the turret. (BHT-ELEC-SPM, Chapter 4).
u. Locate the wires S001E22, S001F22, S007A22, S009A22N, S009D22N,
S009F22N, S009H22N, S010A22N, and S010D22N in the cable assembly (8).
v. Install one contact (4) at the end of each of the wires in step u. using the
crimping tool and the turret. (BHT-ELEC-SPM, Chapter 4).
w. Feed the cable assembly (10, Figure 6) through the side opening of the
backshell (14, Detail A).
x. Using the insertion tool, insert the contacts (4, Figure 7) in their appropriate
location in the connector (3421TR1P1) (5).
y. Attach the two terminal lugs (3) to the shield grounding stud (13, Figure 6,
Detail B) inside the backshell (14) and secure in place with the retained
hardware.
z. Re-assemble the backshell (14) and the cover (15) using the retained screws.
aa. Apply insulation tape (C-548) as required to build the cable assembly (10,
Figure 6, Detail A) diameter.
bb. Secure the cable assembly (10) to the strain relief arm (12, Detail B) with one
tie wrap (C-292).
cc. Connect the connector (3421P1) (4, Detail A) to the receptacle (3421J1) (3) on
the nose forward bulkhead assembly (1).
dd. Connect the connector (3421TR1P1) (8) to the receptacle (3421TR1J1) (9)
under the WU-660 RCVR/XMIT/ANT (3421TR1) (2).
ee. Secure the cable assembly (429-079-530-111) (10) to the bracket (7) on the
WU-660 RCVR/XMIT/ANT (3421TR1) (2) using the clamp (6) and the retained
hardware.
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53. Install the left and right hand chin bubbles 429-330-146-101/-102. (BHT-429-MM,
Chapter 52).
54. If removed, install the forward left and or right side air conditioning evaporators.
Refer to the Air Comm Corporation (STC # SR00693DE).
55. Make an entry in the helicopter logbook and historical service records indicating
compliance with this Technical Bulletin.
56. Return the helicopter to service.
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Figure 1. Nose Structural-Modification (Sheet 1 of 7)
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Figure 1. Nose Structural-Modification (Sheet 2 of 7)
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Figure 1. Nose Structural-Modification (Sheet 3 of 7)
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Figure 1. Nose Structural-Modification (Sheet 4 of 7)
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Figure 1. Nose Structural-Modification (Sheet 5 of 7)
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Figure 1. Nose Structural-Modification (Sheet 6 of 7)
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Figure 1. Nose Structural-Modification (Sheet 7 of 7)
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Figure 2. Radar Door-Installation (Sheet 1 of 2)
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Figure 2. Weather Radar Door-Installation (Sheet 2 of 2)
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Figure 3. TCAS Antenna-Modification
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Figure 4. Aft Radome-Installation (Sheet 1 of 2)
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Figure 4. Aft Radome–Installation (Sheet 2 of 2)
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Figure 5. Forward Radome Diverter Strip Installation (Sheet 1 of 2
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Figure 5. Forward Radome Diverter Strip-Installation (Sheet 2 of 2)
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Figure 6. Weather Radar Receiver, Transmitter Antenna Wiring HarnessAssembly (Sheet 1 of 2)
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Figure 6. Weather Radar Receiver, Transmitter Antenna Cable AssemblyAssembly (Sheet 2 of 2)
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Figure 7. Wiring Diagram
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