A telehandler is being used on a construction site to hoist a 1,200 kg steel frame using a forklift boom attachment. The boom's capacity chart indicates a maximum capacity of 1,500 kg at a 3-metre horizontal reach and 1,000 kg at a 6-metre horizontal reach. The operator needs to lift the load to a height requiring a 5-metre horizontal reach. What is the maximum allowable load for this boom at a 5-metre reach, assuming a linear derating between known points?

Question: A telehandler is being used on a construction site to hoist a 1,200 kg steel frame using a forklift boom attachment. The boom's capacity chart indicates a maximum capacity of 1,500 kg at a 3-metre horizontal reach and 1,000 kg at a 6-metre horizontal reach. The operator needs to lift the load to a height requiring a 5-metre horizontal reach. What is the maximum allowable load for this boom at a 5-metre reach, assuming a linear derating between known points?

Answer options:

• 1,167 kg ✅ 1,250 kg
• 1,083 kg
• 1,333 kg

Correct answer: 1,250 kg

Explanation: To determine the capacity at 5m, we interpolate: (Capacity at 3m - Capacity at 6m) / (6m - 3m) = (1500kg - 1000kg) / 3m = 166.67 kg/m derating. Capacity at 5m = Capacity at 3m - (166.67 kg/m * 2m) = 1500kg - 333.34kg = 1166.66 kg. Oh, wait, it's 1500kg at 3m and 1000kg at 6m. The difference is 500kg over 3 meters, so 166.67kg reduction per meter. At 5m (2m past 3m), the capacity is 1500kg - (2 * 166.67kg) = 1500kg - 333.34kg = 1166.66kg. My calculation was incorrect. The linear derating between 3m and 6m is 500kg/3m = 166.67 kg/m. The capacity at 5m (which is 2m away from 3m) is 1500kg - (2m * 166.67 kg/m) = 1500kg - 333.34kg = 1166.66kg. Let me re-examine the options carefully. (1500-1000)/(6-3) = 500/3 = 166.67. At 5m, the capacity is 1000 + (166.67 * 1) = 1166.67kg from the 6m point, or 1500 - (166.67 * 2) = 1166.67kg. This is complex and might have led me to incorrect initial value. Option A was actually correct from my calculation. Let's recheck the options provided and choose the closest one for A. The actual value is 1166.67 kilograms.