Another feature of Christie's designs was the "convertible" drive: the ability to remove the tracks for road travel, allowing for higher speeds and better range, and reducing wear on the fragile caterpillar track systems of the 1930s.
Outra característica dos deseños de Christie foi a condución "convertible": a capacidade de retirar as cadeas para conducir por estradas, permitíndolle maiores velocidades e mellor alcance, e reducindo o desgaste dos fráxiles sistemas de cadeas dos anos 30.