What is the consequence of an uneven base during crane setup?

• A. It has no effect on stability.
• B. It improves wind stability.
• C. It helps align with wind.
• D. It can cause tipping or instability; requires correction before lift.

Answer: (D)

An even, level base is essential for crane stability. If the base is uneven, the crane’s footprint tilts, shifting the center of gravity toward the higher side and reducing the stability margin. During lifting, loads, arm movement, and wind create moments that can push the crane toward tipping. Because safety hinges on staying within the designed stability envelope, any uneven base must be corrected before lifting — relevel with the outriggers and hydraulic jacks, use cribbing or mats on soft ground, ensure all outriggers have solid, within-tolerance contact, and re-check with a level. If level can’t be achieved, the lift must be postponed.