The near-disastrous crash landing of the Boeing 777 just short of the runway at Heathrow yesterday highlights the danger to the city below that is posed by flights to and from this exceptionally busy airport. What if a plane did crash on London? A terrible disaster, especially if it were densely-populated central London. This is not a far fetched possibility: if I remember rightly, not many years ago a cargo flight from Schiphol airport crashed on to a suburb of Amsterdam. That the victims were mostly impoverished immigrants whose loved ones were not best placed to make a fuss may be why we did not hear a great deal about it afterwards. We hear plenty from the well-funded PR people in favour of airport expansion, mostly talking about employment and economic benefits, but far less about the arguments against. Such disasters do happen. How do you weigh employment and economic benefits against such a risk - to say nothing of the accumulating weight of the environmental case against ai...