A mobile crane is set up on outriggers with a 12 m (40 ft) boom at a 60-degree angle. The load chart indicates a capacity of 10,000 kg (22,000 lbs) at a 10 m (33 ft) radius. If the crane lifts a 9,000 kg (19,800 lbs) load at a 10 m (33 ft) radius, what is the available effective capacity margin?

Question: A mobile crane is set up on outriggers with a 12 m (40 ft) boom at a 60-degree angle. The load chart indicates a capacity of 10,000 kg (22,000 lbs) at a 10 m (33 ft) radius. If the crane lifts a 9,000 kg (19,800 lbs) load at a 10 m (33 ft) radius, what is the available effective capacity margin?

Answer options: ✅ 1,000 kg (2,200 lbs)

• 2,000 kg (4,400 lbs)
• 500 kg (1,100 lbs)
• The boom angle is irrelevant for capacity at a given radius.

Correct answer: 1,000 kg (2,200 lbs)

Explanation: The available capacity is the load chart capacity minus the actual lifted load. In this case, 10,000 kg - 9,000 kg = 1,000 kg. The boom angle is part of how the radius is achieved, but the capacity is directly read from the radius in question.