Chapter 18 Boom Tube Cover

Revision Control Table CHAPTER 18

REVISION DESCRIPTION REMARKS DATE

18.0.0 Original Original Copy – No Updates. 9/16/2015

Chapter 18 Boom Tube Cover Section 18.1 Boom Tube Cover

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Section 18.1 Boom Tube Cover

Notes:

1. Consult Floor Manager when adding a washer or removing a washer.

2. Consult Floor Manager when adding a length to a bolt or taking a length away from bolt.

Indicators to look out for:

1. Additional Operations “+”

2. Caution “!”

3. Critical “!!”

4. Notes

5. INSPECTION POINTS

Chapter 18 Boom Tube Cover Section 18.1 Boom Tube Cover

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1. On the inboard side bottom lip of the Boom Tube Cover [Left (#5430-001) and Right (#5430-002)] attach

the Boom Tube Cover Angle (#5430-005).

! Let the Boom Tube Cover Angle sit flush against the aft end of the Boom Tube Cover and on top of the lip.

2. Starting from the aft end, drill #30 holes every 2” all along the bottom of the Boom Tube Cover Angle,

through the lip.

3. Secure the Boom Tube Cover Angle to the Boom Tube Cover with Rivet, ABL4-2A (#L-42) at each #30

hole. Insert them from the bottom of the Boom Tube Cover towards the top.

4. At the forward bottom end of the Boom Tube Cover, there should be about 1” of lip that is not attached to

the Boom Tube Cover Angle.

5. Cut off 1” of the forward lip of the Boom Tube Cover. This is to give a closer fit to the Hull.

Chapter 18 Boom Tube Cover Section 18.1 Boom Tube Cover

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1. Attach the top edge of the Boom Tube Cover [Left (#5430-001) and Right (#5430-002)] to the exposed

Boom Tube (#5310-012) at the aft end of the aircraft, up against the Boom Tube Bushings [Internal (#5310-

078) and External (#5310-077)].

2. Have the forward edge of the Boom Tube Cover overlap the Turtle Deck (#5340-009) and Hull (#5330-016)

by about 1”.

3. The Elevator Reverse Horn (#2730-012) is inserted through the Elevator Reverse Horn cutout and should be

positioned at the center of the cutout.

4. Starting from the aft end, drill #30 holes at 3/8” from the top edge of the Boom Tube Cover through the

Boom Tube. Layout the holes at 2” increments. Stop just forward of the Vertical Fin Leading Edge (#5530-

020).

5. Rivet using Rivet, SBL44 (#SL-44).

6. Drill a #30 hole where the Left and Right Boom Tube Covers overlap at the forward top and rivet using

Rivet, SBL44 (#SL-44).

Chapter 18 Boom Tube Cover Section 18.1 Boom Tube Cover

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1. At the bottom aft end of the Boom Tube Cover [Left (#5430-001) and Right (#5430-002)] locate the Boom

Cover Attach Strap (#5420-001).

2. Use the hole as a guide to drill a #10 hole through the Boom Tube Cover and Boom Tube Cover Angle

(#5430-005).

3. From the outboard side of the hole, insert a #10-32 x 4/3 Sheet Metal Screw (#S75-1032) with an AN3

Washer (#N3W).

4. Secure the assembly by attaching an AN3 Washer with an AN3 Lock Nut (#N3LN) on the screw end at the

inboard side of the Boom Cover Attach Strap.

Chapter 18 Boom Tube Cover Section 18.1 Boom Tube Cover

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1. On the side of the Boom Tube Cover(s) [Left (#5430-001) and Right (#5430-002)] drill 1” inspection holes

at the following locations:

a. The forward inspection hole is located at 3” below the center of the Elevator Reverse Horn (#2730-

012) cutout and 7” from the forward edge of the Boom Tube Cover.

b. The aft inspection hole is located at 3-1/2” from the bottom edge and 8-1/2” from the aft edge of the

Boom Tube.

Chapter 18 Boom Tube Cover Section 18.1 Boom Tube Cover

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1. Attach the Expansion Plate(s) (#5340-012) to the side of the Boom Tube Cover(s) [Left (#5430-001) and

Right (#5430-002)].

2. Have 1/3 of the forward edge on the Turtle Deck (#5340-009) and Hull (#5330-016). The remaining 2/3 on

the Boom Tube Cover.

3. Align the bottom edge of the Expansion Plate to the bottom edge of the Boom Tube Cover.

4. Drill #30 holes at the top (2) corners of the Expansion Plate into the Turtle Deck and Boom Tube Cover.

5. On the forward edge of the Expansion Plate, under the forward corner rivet, drill evenly spaced #30 holes

down along the edge at about 2” increments. (Total of 6 holes along the forward edge.)

6. Rivet the holes with Rivet, SBL44 (SL-44).

Chapter 18 Boom Tube Cover Section 18.1 Boom Tube Cover

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1. Push the Control Stick in the Cockpit all the way forward and mark the location of the forward edge of the

Elevator Reverse Horn (#2730-012).

2. Push the Control Stick in the Cockpit all the way aft and mark the location of the aft edge of the Elevator

Reverse Horn.

3. Attach the Elevator Control Stop (#3240-098) over the cutout for the Elevator Reverse Horn on the Boom

Tube Cover(s) [Left (#5430-001) and Right (#5430-002)].

4. Center the opening of the Elevator Control Stop with the forward and aft marked lines. Trim if necessary.

5. Drill (8) evenly spaced #30 holes on the Elevator Control Stop and into the Boom Tube Cover.

6. Rivet the holes with Rivet, SBL44 (#SL-44).

7. This is done on both Boom Tube Covers.

Chapter 18 Boom Tube Cover Section 18.1 Boom Tube Cover

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1. Attach the Splash Guard with “V” Shape (#5340-031) to the underside of the Boom Tube Cover(s) [Left

(#5430-001) and Right (#5430-002)] attached to the Boom Tube Cover Angle(s) (#5430-005).

2. The wider side should be in the forward position and the “V” shape is pointing down.

3. Position the Splash Guard as far forward without coming into contact with the aft side of the Hull (#5330-

016).

4. Drill #29 holes at the (4) corners of the Splash Guard into the Boom Tube Cover Angle(s).

5. Install #8 x 1/2” Sheet Metal Screw (#S05-8) at the (4) holes.

Chapter 18 Boom Tube Cover Section 18.1 Boom Tube Cover

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1. Layout the position of the 1/4” hole located at about 46” from the aft of the top side of the Boom Tube

(#5310-012) or about 6” forward of the Vertical Fin Leading Edge (#5530-020).

2. On the Boom Tube Cover(s) [Left (#5430-001) and Right (#5430-002)], drill a 1/4” hole at the laid out

position.

3. Insert a Bolt, AN4-55A (#N455A) through the Boom Tube Cover(s) and thread into the Nutplate, 1/4 – 28

(#NP1/4-28) on the bottom side of the Boom Tube.