In hillingdon the Chiltern Line has had capacity enhancements (a new track to allow fatser running of through trains to Banbury and ultimately Oxford as part of a private sector investment called Evergreen 3).

This is regardless of teh HS2 proposal for most of its route and has space for upgrade and reversing siding between Field End Road and Northolt park station for Rubbish trains so as to keep the waste transfer facility open.

It has been done on time and on budget as I understand it so as to deliver a sustainable upgrade and allow teh slow line round teh south of the waste transer facility (colloquially refferred to as the dump) to link into any London Overground Paddington or Clapham Junction to Denham service via South Greenford)

The Central Line could be diverted after Northolt in tunnel to Heathrow in tunnel via Hayes End and Stckely Park as well as the Heathrow Spur proposed for HS2. Then the South Ruislip to West Ruislip Central Line stretch could be used by Overground and the Ruislip Gardens Depot upgraded and rebuilt to take 'main line / sub surface' stock sized trains. Interchange for teh City and Docklands could be at Old Oak Common for Crossrail as well as the Central Line in Northolt.

A new Depot for tehCentral Line could be under housing development (similar to the White City westfield siding replacements built in the last decade). thsi housing could be dedicated to evacuees from Commonwealth Islands and returning armed forces personnel as well as to maintain the local economy employment base).

If Air capacity to the East of Greater London is upgraded with a Thames Estuary airport and expansion of Stanstead or Southend then RAF Northolt (the diplomatic airport by the A40) could also be sold for housing and Heathrow be used in part as its replacement. Then HS2 trains from Birmingham could use the proposed Ruislip depot track spur and run SOuth Beind teh housing of teh Ruisllip Gardens Estate under RAF Northolt to join the spur if the minor ROyalns living in Bucks and Berks object successfully through the planning process to the Parliamentary proposal of the Governments DFt for the new Misbourne Line under the M25 to a terminal between Iver and West Drayton.

This requires a GLA and dedicated English Parliament transport review and is why there needs to be a devolved English Parliament with statutory powers to raise 'on the books' finance by government bond issues and income tax variance (the latter already done by Edinburgh, the former by US cities such as Boston and New York). It could bring about sustained economic recovery and the restoration of the health of both public and private pension schemes.