Back 73/74 used a sheet J2 rubber job , with ' slot car ' set up .
Slot car motor , a propellor
20 litre drum full of rocks ( it rocked a bit
) slot car speed controller , and 12 V car battery or S. Car Transformer .
Two ball races on the stick got the electrickery thru , rotationally .
This ones the same principle as the antique one ;
Thought a combination of the two ( three car batterys , 36 Volt for voltage drop on 60 ft lines )
Would be lighter than batterys in aeroplane .
Might need a third wire in case the lines shorted out .
At least the motor would stop if the lines melted .
And Wonders , a wheeled trolley for the batteries might make proceeds somewhat less arduous .