In 1938 experiments were conducted to produce an oil dilution system for cold weather operations. In the extremely cold weather that pilots encountered in the northern parts of Canada, special precautions had to be taken to ensure that the oil of their aircraft remained warm. Otherwise, the oil would freeze in the engine, rendering it useless.

Prior to 1938 this involved draining all of the oil after a flight and keeping it warm on a stove overnight. The engine also had to be warmed with a blowtorch prior to returning the oil. A canvas was draped over the nose of the plane to help retain warmth. This arrangement was called a "nose hangar". This process was not only time consuming but also dangerous due to the potential fire hazard.

The Worth system of oil dilution involves the introduction of gasoline to the oil system during shutdown of the engine. The oil, thinned by the gasoline, no longer solidified even in the coldest of conditions. This process also ensured that the oil would provide proper lubrication during startup. On startup the gasoline would then burn off and the oil would return to its normal consistancy.

Thomas William (Tommy) Siers* was credited with the adaptation of the Worth oil dilution system to cold-weather flying in Canada. He was given the McKee Trophy for this feat. He continued working on many projects that greatly impacted aviation, both in contributing to the success of important events, like the MacAlpine rescue venture; and in designing or improving skis, cabin heaters, and carburetor hot spots.