04/27/21
Message Overview:
Message Name:
CORROSION ON INNER TR PANELS
| Identifier: | 783OBS001 |
| Effectivity: | Aircraft 20501 - 20999 |
| System: | Fuselage |
| Associated CAS: | None |
| System Description: | 78-30-00 |
| Schematic Diagram: | None |
| Wiring Diagram: | None |
Message Description:
Operators have reported discovering surface corrosion on the inner panels of the thrust reverser. The area affected is typically along the trailing edge of the upper and lower pivot doors and the fixed side beams. Corrosion typically appears first around the trailing edge rivets and progresses forward with time. The entire Challenger 300 fleet appears to be affected and the level of corrosion seems to correlate more with aircraft usage (flight hours) as opposed to age or environment.
Possible Causes:
- A root cause investigation concluded that the corrosion is likely caused by sulfur based compounds (a product of engine combustion) which breach the protective coating and attack the base material.
Troubleshooting Tips:
Advisory Wire/Service Bulletin:
- AW300-78-0099 - Thrust Reverser Panel Corrosion (20501 - 20999)
- Bombardier SB 100-78-01 (Honeywell/Aircelle vendor SB 78-30-006)
- Bombardier SB 100-78-02 (Honeywell/Aircelle vendor SB 78-30-007)
Forum Articles/Infoservice/Newsletter:
- Forum - Volume 7, Issue 12 (Dist. June 15, 2010) - June 2010
- Infoservice - Challenger 300 2011-2012 Cold Weather Operations
Honeywell Operator Information Wire AS907-OIW-2010-037
Corrosion limits together with a simplified procedure to measure the corrosion depth can be found in Bombardier inspection SB 100-78-01 (Honeywell/Aircelle vendor Service Bulletin 78-30-006). Corroded T/R Assemblies and Pivot Doors can remain in service indefinitely provided the corrosion is within the allowable limit as outlined in the inspection SB. If any components are above the allowable limit continued operation might still be allowed and an SRPSA with the inspection results should be submitted for consideration.
Quick Links:
None
Troubleshooting Recommendations:
- Corrosion limits together with a simplified procedure to measure the corrosion depth can be found in Bombardier inspection SB 100-78-01 (Honeywell/Aircelle vendor Service Bulletin 78-30-006).
- Corroded T/R Assemblies and Pivot Doors can remain in service indefinitely provided the corrosion is within the allowable limit as outlined in the inspection SB. If any components are above the allowable limit continued operation might still be allowed and an SRPSA with the inspection results should be submitted for consideration.