OTTAWA, April 13 (Reuters) - Canada’s airline sector is crucial and the government is looking at helping other carriers, Prime Minister Justin Trudeau said on Tuesday, a day after Ottawa unveiled a C$5.9 billion ($4.70 billion) aid package for Air Canada. Trudeau told a briefing that the Air Canada deal would protect jobs, keep communities connected and ensure passengers received refunds for trips they had not been able to take because of the COVID-19 pandemic. ($1=1.2543 Canadian dollars) (Reporting by Steve Scherer and David Ljunggren)