Beginning September 7, Sean Menke will step in for Jeff Potter as president and CEO of Frontier Airlines. Potter recently announced his resignation, but will remain a member of the Denver-based airline's board. Menke also will join the board. The appointment has Menke returning to the airline after a two-year absence, having previously served as Frontier's senior vice president and chief operating officer before leaving to become executive vice president and chief commercial officer at Air Canada, where he also was promoted to executive vice president of commercial strategy. Frontier on Tuesday also announced other promotions within its senior management team. Chris Collins has been promoted to executive vice president and chief operations officer; Paul Tate to executive vice president and chief financial officer; and David Sislowski to senior vice president and general counsel. Visit [www.frontierairlines.com].