Thanks T3C5, that's very informative.
I am continually amazed at the lack of investment in important infrastructure in this country, and not just in our business. The proposed new tower at EDI was put on the backburner again this week: "sites in the airport's central area are very valuable to us, as they may in future be required for important items of airport infrastructure" said BAA. I think they mean car parks, but I can't be sure.
Do the airlines want an ATC system that works or not? If the answer is (and continues to be) NO then maybe I will apply for a job with Virgin Trains. At least they've invested in some new equipment, and I understand I'll get a pay rise!