NP-158862-001

Revision 1: 10 Jan 2013 Page 1 of 17 Post Office Box 2200 Huntsville, Alabama 35804 USA Telephone: (256) 851-7001 Fax: (256) 859-8822



# Component Service Bulletin

ATR-42 / ATR-72 #2 Forward Side Window

PART NUMBERS

NP-158862-1 NP-158862-2

NOTICE: EAR-Controlled "Technology"

“These commodities, technology or software are controlled by the United States in accordance with the Export Administration Regulations (“EAR”). Diversio n contrary to U.S. law is prohibited.”NP-158862-001

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# Component Service Bulletin

REVISION TRANSMITTAL SHEET

SUBJECT: P/N NP-158862 Service Bulletin for the ATR-42 / ATR -72.

This page transmits Revision 1 of the PPG Service B ulletin P/N NP-158862 for the ATR-42 / ATR-72 #2 Forward Side Window.

REASON
The Service Bulletin is revised to reflect the chan ges listed below.

CHANGES

Revision 1 Addition of Inspection Aid information t o clarify inspection process.NP-158862-001

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# APPROVALS

Prepared By: 10 Jan 2013 Andrew Troller Date Product Support Engineer

Approved By: 10 Jan 2013 Stirling Macfarlane Date Manager, Product Support Engineering

Approved By: 10 Jan 2013 David Lair Date Design Engineer

Approved By: 10 Jan 2013 James Romano Date

Commercial Market Segment ManagerNP-158862-001

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# Component Service Bulletin

SUBJECT: #2 Forward Side Windows (Cockpit Forward Side Wind ows) –Inspection and

Conditional Removal

1. PLANNING INFORMATION A. Effectivity This inspection and conditional removal applies to the components shown below.

Part Number Name Used On NP-158862-1 Left Hand #2 Side Window ATR-42, ATR- 72 NP-158862-2 Right Hand #2 Side Window ATR-42, ATR- 72

B. Concurrent Requirements

None.

C. Reason

1) Origin

Events occurred in which the forward side window wa s separated from the aircraft.

2) Evidence

The investigation performed thus far revealed some anomalies that are considered as physical pre-cursors to the failure and could be associated with an air/water leak at the interface between the z-bar and the external glass and at the interface between the glass and the inner retainer on the int ernal side.

3) Substantiation

The presence of an air/water leak coming from betwe en the z-bar and the outer glass ply or between the inner retainer and inner g lass ply is an indication that structural components within the window have begun to deteriorate.

Note: There are no repair procedures within the Abb reviated Component Maintenance Manual (ACMM) for this type of damage. The attempted repair of this type of air/water leak in the same area, followed b y continued service can allow deterioration of the window structure and can ultim ately result in failure.

The purpose of this service bulletin is to inspect the sealant condition at the level ofNP-158862-001

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the external z-bar and inner retainer for evidence of these physical pre-cursors.

4) Benefits

Accomplishment of this service bulletin will ensure that all #2 forward side windows with a discrepant condition are removed from servic e (See Section 1.C.3).

D. Description

This service bulletin instructs operators to inspec t the z-bar and inner retainer, and to replace any #2 forward side windows that are identi fied as having a discrepant condition (See Section 1.C.3).

E. Compliance

This service bulletin is mandatory. Airworthiness D irective No.: 2009-0159-E was issued by EASA on 20 July 2009 and Airworthiness Di rective FAA AD 2009-18-18 was issues by FAA on 24 September 2009.

F. Approval

The technical content of this document is approved in accordance with CE 1702/2003 regulation and is rendered mandatory by an EASA Air worthiness Directive No.: 2009- 0159-E.

G. Manpower

This service bulletin will require one (1) person a total of .5 man-hours to accomplish the inspection for two (2) windows on a single airc raft (left and right hand #2 forward side windows).

H. Weight and Balance

Not changed.

I. Electrical Load Data

Not changed.

J. Software Accomplishment Summary

Not applicable.NP-158862-001

Revision 1: 10 Jan 2013 Page 6 of 17 K. References

1) PPG Drawing NP-158862, Revision K, dated Novembe r 18, 2010

2) PPG Abbreviated Component Maintenance Manual, A TA No. 56-12-00, Revision 2, dated May 20, 2011.

L. Other Publications Affected

1) PPG Abbreviated Component Maintenance Manual, AT A No. 56-12-00, Revision 2, dated May 20, 2011.

M. Interchangeability or Intermixability of Parts

Not changed.

2. MATERIAL INFORMATION A. Material – Price and Availability

Spare forward side windows may be obtained by conta cting PPG Customer Service at the following address:

PPG Aerospace PO Box 040004 Huntsville, AL 35804 USA

Phone: (256) 851-7001 Facsimile: (256) 851-8822

B. Industry Support Information

All windows identified with the discrepant conditio n (see Section 1.C.3), within PPG warranty, will be replaced free of charge. All win dows outside of PPG warranty will be replaced at charge. Commercial terms have been est ablished and may be discussed with the responsible PPG Account Manager.

C. Material Necessary for Each Component

None.

D. Material Necessary for Each Spare

None.NP-158862-001

Revision 1: 10 Jan 2013 Page 7 of 17 E. Re-identified Parts / Existing Parts Accountabil ity

None.

F. Special Tooling – Price and Availability

None.

G. Special Tooling Necessary to do this Service Bul letin

None.

3. ACCOMPLISHMENT INSTRUCTIONS

A. Provide access to the #2 forward side window ext erior surface through use of a sturdy ladder or other elevated platform. See Figure 1 for window location.

Figure 1 : Location of the #2 Forward Side Window

B. Perform all maintenance tasks necessary to perfo rm interior maintenance on the flight deck windows. C. Remove watches, rings, bracelets, and other meta llic objects that could come in contact with the glass surface of the window

CAUTION : metallic objects can scratch/damage the glass sur face of the window and possibly result in fracture or optical problems for the flight crew.

#2 WindowsNP-158862-001

Revision 1: 10 Jan 2013 Page 8 of 17 D. Equipment needed: A flat, thin, non-metallic shim or taper gauge (0.5 mm or 0.020 in. thick). Use only light pressure to identify existing gaps (do not create g aps with excess force).

Figure 2 : Equipment - Plastic Shim Stock

E. Inspect the periphery of the #2 forward side win dow to identify the following conditions: 1) Standard Condition - See Figures 3 & 4

.

Figure 3 : Cross-sectional View of the #2 Forward Side Windo w – Standard Condition



# Plastic Shim StockNP-158862-001

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Figure 4 : Z-bar & Fillet Seal – Standard ConditionNP-158862-001

Revision 1: 10 Jan 2013 Page 10 of 17 2) Discrepant Condition 1 – Inspect the z-bar for e xisting sealant repair.

Inspect the z-bar for existing repair of the z-bar sealant fillet (See Figures 5 and 6 ). If any evidence of a repair attempt is visible, replace the forward side window.

NOTE 1: a 2.3 mm (.090 in.) sealant fillet at the edge of t he z-bar (See Figures 3 and 4 ) is standard on the window at time of manufacture and may or may not be present on the window depending upon window age and typical wear in flight conditions.

NOTE 2: Removal of any visible repair to the sealant is not allowed and is cause for removal of the window.

Figure 5 : Cross-sectional View of the #2 Forward Side Windo w – Discrepant

Condition Showing an Attempted Repair of an Air Lea k

Figure 6 : Inspection – Discrepant Condition 1



## Example of Sealant over Z-bar and GlassNP-158862-001

Revision 1: 10 Jan 2013 Page 11 of 17 3) Discrepant Condition 2 – Inspect for z-bar defor mation.

This inspection is intended to identify displacemen t or bowing of the z-bar at any point around the periphery of the window (See Figure 7 ).

Figure 7 : Cross Cross-sectional View of the #2 Forward Side Window – Discrepant Condition Showing Z-bar Bowing or Displacement

Use a flat, thin, non-metallic shim or taper gauge to probe at the edge of the z-bar around the periphery of the window. A discrepant c ondition exists if the tip of the shim or gauge penetrates between the z-bar and the outer glass ply in excess of 4 mm (0.160 in). See Figures 8 & 9 showing the #2 forward side window with displaceme nt or bowing of the z-bar and the tip of a non-metalli c shim inserted under the z-bar. In case of a discrepant condition, replace the window.

Figure 8 : Inspection Technique – Discrepant Condition 2NP-158862-001

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Figure 9 : Inspection Technique – Discrepant Condition 2

“On-Wing” Photograph

4) Discrepant Condition 3 – Inspect the gap between the retainer and inner glass ply.

This inspection is intended to identify a separatio n or gap in the sealant bond between the inboard retainer and the inner glass pl y (See Figure 10 ).

Figure 10 : Cross Cross-sectional View of the #2 Forward Side Window – Discrepant Condition Showing a Gap Between the Retainer and In ner Glass PlyNP-158862-001

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Use a flat, thin, non-metallic shim or taper gauge to probe at the edge of the inboard retainer around the periphery of the window . A discrepant condition exists if the tip of the shim or gauge penetrates between the retainer and the inner glass ply in excess of 7.5 mm (0.300 in) or for smaller s eparations with cumulated length exceeding 300 mm (12 in). See Figures 11 & 12 showing the #2 forward side window with a gap between the retainer and the inne r glass ply and the tip of a non-metallic shim penetrating the gap. In case of a discrepant condition, replace the window.

Figure 11 : Inspection Technique - Discrepant Condition 3

Figure 12 : Inspection Technique - Discrepant Condition 3

“On-Wing” PhotographNP-158862-001

Revision 1: 10 Jan 2013 Page 14 of 17 5) Discrepant Condition 4 – Z-bar deformation and r etainer gap at the same location.

This condition exists when discrepant condition 2 ( z-bar deformation) and discrepant condition 3 (inner retainer gap) co-exis t at the same hole locations (See Figure 13 ).

Figure 13 : Cross Cross-sectional View of the #2 Forward Side Window – Discrepant

Condition Showing Both a Z-bar deformation and a Ga p Between the Retainer and Inner Glass Ply

Any window showing both sealant separation between the z-bar and outer glass ply, and separation between the inboard retainer an d inner glass ply, common to the same hole location and with at least one of the se discrepancies exceeding a length (span) of 225 mm (8.86 in / approximately 6 holes) identifies a discrepant condition and shall be replaced. See Figure 14

.

Figure 14 : Inspection Technique – Discrepant Condition 4NP-158862-001

Revision 1: 10 Jan 2013 Page 15 of 17 6) Discrepant Condition 5 – Z-bar deformation and r etainer gap in window corner.

This condition exists when discrepant condition 2 ( z-bar deformation) and discrepant condition 3 (inner retainer gap) co-exis t in same window corner.

Any window showing both sealant separation between the z-bar and outer glass ply, and separation between the inboard retainer an d inner glass ply, common to the same window corner and with at least one of the se discrepancies including the entire arc of a window corner identifies a discrepa nt condition and shall be replaced.NP-158862-001

Revision 1: 10 Jan 2013 Page 16 of 17 F. Accomplishment Report:

Fill in the enclosed Accomplishment Report (Page 12 ) and send it to both:

ATR techdesk 1 ALLEE PIERRE NADOT 31712 BLAGNAC CEDEX FRANCE Phone: +33 (0)5 62 21 62 21 Fax: +33 (0)5 62 21 67 18 Email: techdesk@atr.fr

PPG Aerospace ATTN: Andrew Troller P.O. Box 2200 Huntsville, AL 35811 USA Phone: +1 256 859 2500 ext. 2544 Fax: +1 256 859 8155 Email: atroller@ppg.com

G. Should the window need replacement, it should be returned to PPG Aerospace for further analysis at the following address:

PPG Aerospace 1719 Highway 72 East Huntsville, AL 35811 USA

ATTN: Andrew Troller

Phone: +1 256 859 2500 ext. 2544 Fax: +1 256 859 8155NP-158862-001

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