Taken from External Plant News - No. 23 January 1972
The Mark III units comprise a forward control 30 cwt Landrover on which is mounted a Spencer HM28 platform. The Landrover is equipped with a high/low range transfer gearbox which provides four wheel drive and allows the vehicle to be driven very slowly with a man in the cage. Spring lockouts ensure adequate stability of the vehicle, throughout the range of movement of the platform, which gives a working height of 29 feet and an outreach of 13ft 6ins. Steel pipework is used wherever possible in the hydraulic circuit to give a cleaner layout and reduce out of service time due to hose failures.
An 8 Hp Kohler auxiliary petrol engine provides power for the platform hydraulics and the 110 volt AC generator. This unit is mounted at the rear of the vehicle on a sub frame, and is easily removable for maintenance. The area between the back of the cab and the platform turntable is now left clear for storage of recovered line plant. A clip-on canvas cover affords weather protection when the engine is not in use.
The cabling winch now has two operating speeds and its power has been increased to provide a line pull of 800 lb. It is mounted at the rear of the vehicle and is equipped with a fail safe brake to maintain line tension during cabling operations. The winch drum normally holds 250 feet of nylon rope and its operation is controlled by hand switches in the cage or at the rear of the vehicle. Foot control, enabling the operator to have both hands free for capstan operation of the winch is also provided.
The cage toolbox has been specifically designed to hold small tools and stores required for aerial cabling. Removable covers fitted over the cage openings give some weather protection to the operator, and the loud speaker intercommunication system has been improved and features an override button at the cage so that the operator in the cage can always speak to the driver.
An emergency hand pump gives full movement of the platform
in the event of failure of the engine or hydraulic system. The
lockerwork remains substantially unchanged except for locking latches fitted
to the doors in place of the padlock hasps and provision of an additional
locker to carry muddy boots and cans of petrol.
Last revised: November 18, 2017