The National Post reports in its Wednesday, Jan. 21, edition that the proponents behind a proposed hydrogen-powered passenger train linking the Calgary airport to Banff say the endorsement of construction trades unions is another sign of the proposal's viability. A Postmedia dispatch to the Post reports that on Tuesday, Canada's Building Trades Unions and the Building Trades of Alberta signed a memorandum of understanding to collaborate with Calgary Airport to Banff Rail (CABR). The groups behind the $2.6-billion project -- Infrastructure investor Plenary Americas and Banff-based Liricon Capital -- have been pushing for the proposal to be adopted by Ottawa's Major Projects Office, which fast-tracks proposals deemed to be in the national interest. The proposed train would link the airport, downtown Calgary and Banff, following the existing CPKC freight corridor along new parallel rails. The train would travel the 150-kilometre corridor along the Canadian Pacific Kansas City route to Banff to provide service to visitors to the national park as well as commuters. The project, say the proponents, would help revitalize Calgary's downtown.