InvestmentsTop Global NewsMarketsReal Estate Air Canada files challenge over Onex’s CUS$3.5 billion buyout of rival WestJet By financialnews_rlv83x - September 3, 2019 0 125 Air Canada has challenged Onex Corp’s proposed acquisition of WestJet Airlines , on grounds that the deal may not meet the country’s ownership rules, according to a letter sent by the carrier to the Canadian Transportation Agency.