[A320] V2500 VSV Interaction Messages( LP reroute design)

Summary:

This document addresses a reported occurrence of "ENG x COMPRESSOR VANE" ECAM warnings experienced on certain A319/A320/A321 aircraft powered by IAE engines during specific flight phases. These warnings are associated with the Variable Stator Vane (VSV) system and are more prevalent in hot weather conditions.

Background:

Investigations identified a combination of factors contributing to the issue, including:

• VSV system friction: Increases with wear and ambient temperature.
• High day temperatures: Further exacerbate VSV friction.
• Fuel pressure limitations: Can hinder VSV movement.
  

This combination can lead to insufficient force in the VSV system, triggering "ENG COMP VANE E/W" track check faults.

Resolution:

• Temporary Software Update: A Temporary Software Modification (TSM) has been implemented to mitigate the issue's impact.
• VSV Actuator LP Reroute (LPRR) Modification: Initially introduced through IAE SB 73-0219 and Airbus SB 73-1098 to enhance VSV force. However, this modification was discontinued due to identified fuel line damage concerns.
• LPRR De-Modification: Currently underway for affected engines (39 as of May 2013).
• Alternative PRV Study: Abandoned due to limitations in the LPRR solution's robustness and reliability.
• Permanent Fix: A new, redesigned VSV actuator (resized VSVA) will be implemented as the permanent solution, addressing the root cause of the issue.
  

Recommendations:

• Refer to IAE SB 73-0219 and Airbus SB 73-1098 for details on the LPRR modification and de-mod procedures (if applicable).
• Continuously consult the latest technical documentation and airworthiness directives for specific guidance and updates.
  

Note: This information is for general awareness only and should not be used for operational decision-making. Always refer to official regulatory sources for complete and accurate directives.