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120 21.6 52
140 25.2 51
*Assume 1.8m row width
Table 2.9 shows the average breakdown of operations across a 14-hour harvesting day from eight
harvesters in the Mackay region. These data show that on turning at the end of rows and waiting for
the mill to supply bins can consume nearly as much time as actual cutting time.
Table 2.9 Field efficiency for Australian harvesting (Sandell and Agnew, 2002)
Operation Time % of Time
(Hours:minutes)
Cutting 6:15 45
Turning 2:50 20
Waiting for bins 2:42 20
Rest 0:59 7
Other Downtime 0:52 6
Servicing 0:22 3
Mallee System
The dispersed nature of the crop will have a significant impact on field efficiency. The yields per km
of row will be about 20 to 40 green tonnes. However, because the mallees are in narrow dispersed
belts, the yield per paddock hectare will be less than 5 green tonne per hectare, and typically around 1
green tonne per hectare. Therefore, the haul distance will vary from hundreds of metres to several
kilometres, which will make the logistics of harvesting and infield transport critical to minimising the
time lost by both harvesters and haulouts.
Modelling as part of this project has illustrated that because the rows of mallees are typically long,
and the harvester’s speed will be low, the 20% of time spent turning in sugar cane will be reduced to
about 5% (see Section 7.3). With close coordination between the harvester and the haulouts to
minimise waiting for bins, it appears possible that harvester utilisation in the vicinity of 70% - 80%
may be achievable.
It is a challenging objective to achieve such high levels of utilisation in the mallee crop configuration,
with the dispersed crop and capital intensive harvesters and haulouts. One option under consideration
is to use infield transport for short hauls (up to about 2 km) to short-term landings in the corner of the
paddock, and maintain the ratio of two haulouts per harvester. This will ensure that all three machines
are as fully utilised as possible, with the emphasis upon maintaining harvester utilisation.
The paddock corner landings will in many cases not be accessible by conventional road transport
prime movers, and it is proposed to establish road transport landings widely spaced across a district,
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