Suspect Wing Surface Mechanism Issue
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Background
Section titled “Background”Use this guide when a wing control surface needs hardware inspection for suspected sticky, binding, range-limited, or linkage-related behavior.
Possible causes include:
- Hardstop damage or misalignment
- Mechanical binding in the hinge or linkage
- Torque tube disconnection (EV3)
- Interference with surrounding structure
Generally, there are four classes of hardware failures:
- Friction: retry the test, either the EOL test or the pre-flight check. If it fails again, replace the wing. The removed-part flow references the UMM rework procedure.
- Over range: the motor can move beyond the expected range, which generally indicates a failure in the linkage between the torque tube and the motor. Replace the servo/linkage as an off-wing maintenance action.
- Under range: the motor cannot reach full range or deflection and is likely binding or seeing high friction. Retry the test, either the EOL test or the pre-flight check. If it fails again, replace the wing.
- Comms issues: intermittent comms can be caused by servo motor electrical failure, M5 connector or harness damage, or flex harness damage. Replace the wing and/or harness, as required.
Hardware-related wing servo issues should drive immediate wing replacement in the field to restore the aircraft. Test and repair the removed wing at the hub with proper equipment, then return it to inventory as a serviceable spare.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
are-you-troubleshooting-an-ev2-or-ev3{"<small><b>Step 1</b></small><br/>Question: Are you troubleshooting an EV2 or EV3..."}
ev2-remove-the-outboard-wing["<small><b>Step 2</b></small><br/>Action: Remove the outboard wing from the air..."]
ev2-inspect-the-servo-linkage{"<small><b>Step 3</b></small><br/>Question: Inspect the servo linkage assembly on..."}
ev2-raise-wing-discrepancy-linkage["<small><b>Step 4</b></small><br/>Action: Link the issue to RCCA ticket ISS-71..."]
ev2-manually-actuate-control-surface{"<small><b>Step 5</b></small><br/>Question: Manually actuate the control surface...."}
ev2-raise-wing-discrepancy-friction["<small><b>Step 6</b></small><br/>Action: Link the issue to RCCA ticket ISS-98..."]
ev2-raise-wing-discrepancy-no-obvious-damage["<small><b>Step 7</b></small><br/>Action: Raise a discrepancy against the wing ..."]
ev3-remove-and-replace-the-wing["<small><b>Step 8</b></small><br/>Action: Remove the wing from the aircraft and..."]
ev3-raise-wing-discrepancy["<small><b>Step 9</b></small><br/>Action: Raise a discrepancy against the wing ..."]
are-you-troubleshooting-an-ev2-or-ev3 -->|EV2| ev2-remove-the-outboard-wing
are-you-troubleshooting-an-ev2-or-ev3 -->|EV3| ev3-remove-and-replace-the-wing
ev2-remove-the-outboard-wing --> ev2-inspect-the-servo-linkage
ev2-inspect-the-servo-linkage -->|Yes| ev2-raise-wing-discrepancy-linkage
ev2-inspect-the-servo-linkage -->|No| ev2-manually-actuate-control-surface
ev2-manually-actuate-control-surface -->|Yes| ev2-raise-wing-discrepancy-friction
ev2-manually-actuate-control-surface -->|No| ev2-raise-wing-discrepancy-no-obvious-damage
ev3-remove-and-replace-the-wing --> ev3-raise-wing-discrepancy
style are-you-troubleshooting-an-ev2-or-ev3 fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style ev2-remove-the-outboard-wing fill:#dcfce7,stroke:#22c55e,color:#14532d
style ev2-inspect-the-servo-linkage fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style ev2-raise-wing-discrepancy-linkage fill:#dcfce7,stroke:#22c55e,color:#14532d
style ev2-manually-actuate-control-surface fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style ev2-raise-wing-discrepancy-friction fill:#dcfce7,stroke:#22c55e,color:#14532d
style ev2-raise-wing-discrepancy-no-obvious-damage fill:#dcfce7,stroke:#22c55e,color:#14532d
style ev3-remove-and-replace-the-wing fill:#dcfce7,stroke:#22c55e,color:#14532d
style ev3-raise-wing-discrepancy fill:#dcfce7,stroke:#22c55e,color:#14532d Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
Are you troubleshooting an EV2 or EV3 aircraft?
2 action
Remove the outboard wing from the aircraft per UMM 57.2.2.e Remove Outboard Wing. Install a serviceable replacement wing to restore the aircraft.
3 question
Inspect the servo linkage assembly on the removed wing. Is the linkage damaged, disconnected, or missing hardware?
4 action
Link the issue to RCCA ticket ISS-71238, then raise a discrepancy against the wing in ZerpMX. Then follow the Removed Wing Flowchart.
5 question
Manually actuate the control surface. Does it feel like there is a lot of friction?
6 action
Link the issue to RCCA ticket ISS-98886, then raise a discrepancy against the wing in ZerpMX. Send the damaged wing to mx holding for structure repair rework following 51.6.4.d Repair Wing Control Surface Friction or Binding. Then follow the Removed Wing Flowchart.
7 action
Raise a discrepancy against the wing in ZerpMX and follow the Removed Wing Flowchart for removed-part testing and disposition.
8 action
Remove the wing from the aircraft and install a serviceable replacement wing to restore the aircraft.
9 action
Raise a discrepancy against the wing in ZerpMX. Then follow the Removed Wing Flowchart.
Resolution note
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