When you finally start comparing like with like Shed, people may take your argument more seriously, but your insistence on comparing R2 at Manchester(which was indeed a new runway and associated taxiways) with the third runway at Heathrow (which includes a new runway, taxiway, aprons, terminal, satellites, road and rail infrastructure and over £1bn of compensation to local residents) undermines your case.
OK then. Let's uncompromisingly compare like with like. Inflation adjusted cost of MAN 23L/05R plus supporting taxiways: £273M. Budget for expanding MAN's apron and transforming the entire terminals complex (mainly new build) providing capacity for 30M+ pax per annum: £1Bn. Now, how about costing in some surrounding infrastructure. Manchester Airport Metrolink Extension (9 Mile Route + Stations): £398M. And let's throw in a new major road - A6 MARR: £290M. Total cost for the bundle: £1.961Bn.
So how does that combined total compare with LHR R3 projections? A long-haul capable runway, a vast total terminals rebuild, a major dual-carriageway road and a twin-track light rail link to the city all for under £2Bn. These numbers expose the outrageous cost of the LHR proposal. And if £2Bn buys what I just listed in the North, just imagine what £5Bn of direct infrastructure investment could do for Liverpool! Because that 'rounding error' £5Bn happens to be the low-end estimate of the public contribution (by you!) to the LHR works, though the highest estimate is £20Bn and the most credible estimate is £10Bn. Don't forget this would be just the latest in a long series of major infrastructure innovations which you have contributed to on behalf of London and the SE.
Those of you who seriously believe that this magnitude of additional public spending concentrated in the SE (before even considering Crossrail 2!) is a good deal for Merseyside need to sit down with a calculator and an Aspirin. Trickledown is a joke. If you genuinely care about Liverpool you need to up your game and lobby your MP's to demand
direct infrastructure investment. Up here. Three A319's per day to LHR - which may not even happen - is no substitute.