Lethbridge Airport had become more regional in nature. According to Trans-Canada's system timetable dated April 29, 1962, the airline was operating Vickers Viscount turboprop service on a routing of Lethbridge-Calgary-Edmonton and was also flying Douglas DC-3 service with a routing of Lethbridge-Medicine Hat-Swift Current-Regina-Yorkton-Brandon-Winnipeg. Trans Canada would become Air Canada which in turn continued to operate Vickers Viscount turboprop service on the Lethbridge-Calgary-Edmonton route before ceasing all scheduled passenger service to Lethbridge during the early 1970s. Time Air was a regional airline that initiated operations in Lethbridge. Founded in 1966 as Lethbridge Air Service, Time Air flew a variety of turboprop aircraft
Turboprop Kaman's K-125 synchropter, which used a Boeing T50 turboshaft engine to power it on 11 December 1951. Compared to turbofans, turboprops are most efficient at flight speeds below 725 km/h (450 mph; 390 knots) because the jet velocity of the propeller (and exhaust) is relatively low. Modern turboprop airliners operate at nearly the same speed as small regional jet airliners but burn two-thirds of the fuel per passenger. However, compared to a turbojet (which can fly at high altitude for enhanced speed and fuel efficiency) a propeller aircraft has a lower ceiling. The most common application of turboprop engines in