Heathrow trials steeper approaches as runway decision looms

That's a whopping 35m difference in height (559m vs. 524m) 10 km from the airport. The difference in noise levels will be almost insignificant.

Heathrow will get the third runway, noise or no noise. The committee looking at London airports expansion rightly dismissed Johnson's vanity project of an environmentally damaging airport in the Thames estuary, as well as Gatwick's access difficulties for passengers north and west of London. It has to be Heathrow.