What action is specified for jack legs with cracks less than 1/2 inch?

What action is specified for jack legs with cracks less than 1/2 inch?

• A. Replace
• B. Stop drilled and welded
• C. Inspected and monitored
• D. Ignore

Answer: (B)

Small fatigue cracks in jack legs can be arrested and repaired using an approved stop-drill and weld procedure when the crack size is under a specified limit. Stopping the crack with a small drill hole at the crack tip relieves the local stress concentration and halts further propagation. After stop drilling, welding is performed per the aircraft’s repair data to restore the cross-section and load path, returning the component to airworthiness without needing full replacement. This approach is allowed only because the repair data specify it for cracks of this size and the area is then re-inspected to confirm structural integrity. Ignoring the crack or simply leaving it unattended would risk continued growth and potential failure, while replacement isn’t required for such a small crack when the approved repair method is available.

Small fatigue cracks in jack legs can be arrested and repaired using an approved stop-drill and weld procedure when the crack size is under a specified limit. Stopping the crack with a small drill hole at the crack tip relieves the local stress concentration and halts further propagation. After stop drilling, welding is performed per the aircraft’s repair data to restore the cross-section and load path, returning the component to airworthiness without needing full replacement. This approach is allowed only because the repair data specify it for cracks of this size and the area is then re-inspected to confirm structural integrity. Ignoring the crack or simply leaving it unattended would risk continued growth and potential failure, while replacement isn’t required for such a small crack when the approved repair method is available.