Which is what I was arguing was a far better option than increasing APD at LHR i.e. carrot for the regions, rather than stick for LHR.
Of course if the aviation industry had its own way then the Government would agree to 4 runways at LHR and abolish APD all together, on the premsie that the associated increase in business and GDP would more than cover the loss in APD. But then that would presume we have a right wing laissez-faire government, rather than the leftist social one we apparently do.