Shifta Products (www.shifta.com) makes caravan movers that are powered by
Parvalux dc motor/gearbox units. They are capable of moving double-axle
caravans weighing in the region of 2,000kg over uneven surfaces and up
inclines as steep as one-in-three. When an aircraft owner saw a Shifta
unit in action, he approached the company to see if it could be adapted
to move a light aircraft from a hanger to the apron, essentially to
replace petrol driven movers that can be difficult to start and control
with any degree of smoothness.
The first challenge for Shifta was to find a motor/gearbox unit of
sufficient power to pull a 3,000kg plus dead weight. Those that it was
using for the caravan movers were simply not up to the job. Parvalux set
about the task and provided sample motor/gearboxess with greater power
ratings for Shifta's evaluation. The aircraft mover comprises a steel
frame housing two 12V dc batteries and chargers on either side. The
re-engineered motor/gearboxes are mounted adjacent to the drive wheels,
which are connected directly to the gearbox output shafts, and provide an
impressive 250Nm each. The unit is controlled via a joystick, providing
forward and reverse drive at a speed determined by the joystick
deflection.
The unit was recently put through its paces at East Midlands airport,
making light work of moving a Beech Baron 58P twin engine aircraft
weighing in excess of 2,800kg.