Forestry Commission - Hydrostatic Tractor
Photograph is courtesy of Jim Christie, Crook of Devon, a former senior mechanical engineer in the Forestry Commission.
The following detail in from Leaflet 59 found as Picture No 4553
Prototypes were produced between 1969 and 1973 varying in power from 43 to 75 brake horse power (BHP). It appears that they used Carron or should it be Caron NEL ball motors to power the two winches but no mention of what powered the wheels. Origin of the Ball Motors not certain but most likely Caron (American?)
The images show the first and also Mark III versions, mentions engine types tried and also that the two winches were radio controlled. Was this a first radio controlled?
Trials were carried out at Alice Holt, Dean, Kielder, Wauchope, Glentrool, Rheola, Dunkeld and Solway Forests and these along with regular working from the machines based at a few forest indicated reasonable production outputs and it was decided to pass production to Roadless Traction Ltd, of 717 London Road, Houslow, Middlesex in 1974. The Commission intended to purchase the first 12 machines produced in the first seven months but supply was delayed at time of writing in 1974.
There is no great mention of initial details other than that R B Ross was the designer, his staff built it and it was tested by Athol Wayman and his experimental team. The author of the leaflet is W O Wittering, head of Work Study branch.
Can anyone name the driver and the man standing nearby?
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Groups: Forest Research, Forestry in Action, Timber harvesters, processors, forwarders and cable cranes