[Etheryte]

Adding a runway to an existing airport is relatively low risk and comparatively cheaper than building a new major airport altogether. Anyone considering the latter will surely look at the Berlin Brandenburg Airport [0], which ran roughly €4 billion over budget and opened nine years behind schedule. Given the dire financial situation of the United Kingdom right now, I would wager this is an incredibly hard sell.

[0] https://en.wikipedia.org/wiki/Berlin_Brandenburg_Airport

[nickdothutton]

Cheaper and lower risk still just to abolish the noise restrictions on the existing airport, allowing it to run 24-7.