Wing Landing/Taxi Light Lens

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REFERENCE NO: AW700-33-0842 INFORMATION TYPE: Maintenance ATA: 33-41 EFFECTIVITY: Global 7500 SUBJECT: Wing Landing/Taxi Light Lens AW700-33-0842 Basic Issue: December 21, 2022 Page 1 of 3 1. REFERENCES: 1.1 Global 7500 Illustrated Parts Data Publication (IPDP) - BD700-A-J33-41-11-01AAA-941A-A - Wing landing-light lenses 1.2 Global 7500 Aircraft Maintenance Publication (AMP) – BD700-A-J12-00-00-02AAA-398A-A – Aircraft Walkaround (for maintenance) – Aircraft system configuration 1.3 IS700-33-7001 Rev. A - Lights - Landing Taxi Light - Lens Erosion Protection 1.4 GREO 700-33-41-7002 - General Temp Disposition – Landing Light Lens – Re-Bonding 1.5 GREO 700-33-41-7003 - General Temp Disposition – Landing Light Lens – Tape Application 1.6 GREO 700-33-41-7001 Rev. A - General Temporary Repair - Landing / Taxi Light 2. INTRODUCTION: This Advisory Wire (AW) is to inform Operators of a condition where either the left hand or right hand Wing Landing/taxi Light (WLL) lens may disbond from the WLL assembly. This AW contains recommendations to visually inspect the WLL lenses regularly for signs of degradation and provides information on the mitigation actions available to prevent flight interruptions. AW700-33-0842 Basic Issue: December 21, 2022 Page 2 of 3 3. DESCRIPTION: The WLL assembly (Figure 1) includes two Light Emitting Diode (LED) light clusters where a polycarbonate lens is covering the assembly. This lens is held by an aluminum bezel (Figure 2) that is attached he WLL assembly (Ref. 1.1). Figure 1: WLL assembly Figure 2: WLL lens and bezel Bombardier has received reports where a disbonding condition was observed at the aluminum bezel and polycarbonate lens interface (Figure 3). This condition, if not identified on the ground during the maintenance or pre-flight walkaround (Ref. 1.2), could result in water ingress into the wing landing light enclosure. In certain instances, this condition has led to a lens detachment from the aircraft in-flight. Figure 3: Bezel / Lens Interface AW700-33-0842 Basic Issue: December 21, 2022 Page 3 of 3 4. ACTION: To minimize the risk of occurrence of the condition described above, Bombardier recommends operators pay special attention to the bezel/lens interface during the walkaround procedure (Ref. 1.2) and to incorporate the IS Modsum IS700-33-7001 (Ref. 1.3) at the next maintenance opportunity. This IS Modsum provides instructions to apply a layer of protective tape on the WLL lens to prevent erosion at the bezel/lens interface. Should there be evidence of bezel/lens interface not properly sealed or bonded, Bombardier has issued two temporary General Repair Engineering Order (GREO) 700-33-41-7002 (Ref. 1.4) and 700-33-41- 7003 (Ref. 1.5) to provide temporary bezel/lens interface re-bonding or tape application instructions to allow continued operation until a replacement of the lens is carried out. In the event were a WLL lens is found missing after a flight, Bombardier is offering the option to install a blanking plate as a temporary repair to continue operations until a spare lens is available for replacement. The blanking plate detailed drawing and the engineering authority to install it on the aircraft are included in the temporary GREO 700-33-41-7001 (Ref. 1.6). Bombardier has planned to have few blanking plates available at the SPARES depot for customers direct ordering. Considering the stock levels of the replacement WLL lens are critical now, Bombardier recommends incorporation of the IS Modsum (Ref 1.3) at the earliest convenient time. The three GREOs (Ref 1.4, 1.5 & 1.6) require incorporation only in cases a WLL lens is found disbonded or missing. The IS Modsum (Ref 1.3) and GREOs (Ref 1.4, 1.5 & 1.6) are available on the Bombardier Customer Portal. Bombardier and the supplier are working on a design evolution of the WLL lens assembly. A full-size polycarbonate lens mounted on the aircraft type of design is being evaluated to replace the existing bezel/lens design. Operators will be kept informed of the progress of the investigation via revision of this AW. Should you have any questions pertaining to this AW or require additional information, please contact your Bombardier Field Service Representative (FSR) or the Customer Response Center (CRC).