In 1942 The British Ministry of Supply asked Canada for an oversnow vehicle that could be used as a supply vehicle, a personnel carrier and a spg. Initially it was suggested that the prototype be built by Bombardier as they had experience with the Bombardier B12 and the military rather liked the vehicle. Regardless the British insisted on GM be the ones to build the prototype, most likely due to Bombardier being too small to take on the order. Though GM did build the prototypes they used Bombardier as a reference causing the two to visually appear similar. The problem was that the GM Snowmobile was too similar to the Bombardier as the vehicle had similar payload capacity of 725kg, but was much heavier at 5,200kg.
However while GM had copied Bombardier they still had no experience in building such a vehicle. As a result several flaws became known during initial testing, most notably it was noticed that snow was able to make it’s way into the engine compartment. This cause repeated problems with the engine become too cold and not starting. The biggest problem that the found with the prototype was the front skis. While a lot of effort went into make them it was found that they were too complex, which led to multiple instances of failure and short operational expectancy. The skis were made with independent suspension and were designed to steer, however the vehicle had the redundancy in that the tracks could brake steer as well. In the end the prototype continued with the trials with the front skis removed. This worked, but it was forbidden to drive the vehicle downhill due to the vehicles off-center of gravity.
In March 1943 the vehicle was tested at Petawawa along with the Universal carrier as a self propelled mount for the Bofors 40mm L/60. It was found to be descent in the role, but the weight issues were still prevalent.
By July 1943 British interest in the vehicle waned and it was cancelled shortly after. The High Capacity Snowmobile while a failure in the end did set the foundation for future oversnow vehicles. This includes the Armoured Snowmobile mk. 1 and 2, the Mudcat, and the Canadair Cl-70 RAT personnel carrier. Ironically after the cancellation Canadian Authorities went back to Bombardier to make an armoured snowmobile, which resulted in the Bombadier Kaki in 1943. The Kaki would later be the basis for the Mk 1. armoured snowmobile.
As a personnel carrier
Bofors 40mm in game stats
Belt Penetration @ 0° Angle of Attack (mm)
10 m 100 m 500 m 1,000 m 1,500 m 2,000 m
Default 72 69 58 46 37 29
Mk.II 3 3 3 3 3 3
M81A1 72 69 58 46 37 29
Lucy, Roger. Secret Weapons of the Canadian Army. Pg 64, 111-112.