What are the five parts of a haul cycle?

Loading at the shovel, hauling loaded, dumping, returning empty, and delay. Cycle time is the sum of the five.

Which part of the haul cycle usually loses the most time?

It depends on the mine, which is why each part has to be measured. Queues at the shovel or crusher and unrecorded delays are common losses that a shift total hides.

How is each part of the cycle measured?

GPS and status data from an in-cab terminal on each dumper mark when it spots, leaves loaded, tips and returns. Minocular splits every trip into the five parts automatically.