Guardian: A coalition of local councils, green groups and residents will today mount a legal challenge to government plans for a third runway at Heathrow airport. The coalition’s lawyers will argue at the high court in London that the government’s consultation process for Heathrow expansion was fundamentally flawed. The then transport secretary Geoff Hoon gave the go-ahead for the expansion in January last year, but the Conservatives are opposed to a third runway. The coalition, …