Ok, I think i have found the case
Air Services vs Canadian Airlines International
This was part of the bunfight between Airservices and owners of aircraft leased to the failed Compass. Aircraft were held in lien until fees were paid. Clever dicking on meanings of words changed the way AirServices was able to charge per Landing (note- judge was upset that take-offs were free??? and outgoing flights weren't charged??You'd think airservices would have been able to explain that one!) in one aerodrome would incur charges for the other 31 sched 1 airports(Once again airservices sucked the big on on that too) The way things were set up it was tax, instead of a reasonable fee incured for the specific aerodrome. Suffice to say, Because of wording The entire network of aerodromes atc and rffs was able to be broken up into the separate entities we see today. Instead of saying any flight into Australia or within Australia incurs a charge of $x per tonne per nm traveled in enroute fees whilst within Australian Airspace. A landing at any one of 31 Sched 1 aerodromes incurs a cost of $y per tonne to cover terminal nav charges and rff as per requirments as based in the Chicago convention of 194whatever. A landing includes a takeoff, no extra terminal charges are incured for the takeoff phase, these are included in the term landing.
Anyway, quite a clever way of trying to get back money payed to get your toy out of hock. All claimants agreed to en-route charges but worked a way of beating the network charge. So much so that GA had to receive a SUBSIDY up until OCT05 to insulate them from charges that should have been incured by flying into some of the regional aerodromes that AirServices was required to give a service. Cross subsidisation was a big no no to the economical rationalists of the Hawke Keating ERA.
This case only relates to charges across a network. Cross subsidising less used aerodromes by fees from busier aerodromes was on the nose according to the high court in this case.
OK, I cannot vouch for how an Irishman or a British record king will bounce when the dollar finally drops. They are recipients of a service and must pay a REASONABLE FEE to cover costs as set out by AirServices from time to time.
Am I making sense so far?
AirServices must supply a radar service, enroute and terminal traffic services as well as navaids. For which a service fee must be charged. There is nothing to stop AirServices facilitating fitment as part of the equipment purchases for a new radar system. All that is required will be a fully costed plan submitted to the directors and signed off by the Minister to allow a subsidy to continue. This, as yet, hasn't happened! the argument shall remain academic.
Like the owners of the aircraft in hoc, the airlines may well challenge these "subsidies" in the high court but like the owners it will be after the fact. Do they really have a say in how much AirServices charges? AirServices was caught once on wording, I do not think they will get caught again!