Sikorsky S-51 Served as the RCAF's first helicopter, used for training and experiments. Two accompanied Admiral Richard E. Byrd on his 1946-1947 Antarctic expedition (as the first helicopters to fly in the Antarctic). First flight was in February 1946. 

https://ingeniumcanada.org/artifact/sikorsky-s-51-h-5-dragonfly

4" 6"