You have four 35-ton, off-highway trucks hauling from a pit to an airfield job. The haul road is maintained by a grader and has a rolling resistance of 80 lb/ton. The road is essentially level and the distance is 2.1 miles (one-way). The gross weight of the truck when loaded is 70 tons.

a. What is the power required on the haul to the fill location?

b. What is the maximum speed when hauling to the fill?

c. What are the travel times to and from the fill (i.e., loaded and empty)? The trucks are being loaded by a shovel with a 5-yard bucket (assume seven load cycles per truck load). The cycle time for the shovel is 0.5 minutes.

d. What is the total truck cycle time?

e. What is the production of this system in cubic yards per hour assuming the trucks carry 35 CY per load?

f. Is the system working at, above, or below its balance point?