In what can only be described as a spectacular own goal, the UK government's Department for Transport has apparently done the maths on Heathrow's long-awaited third runway - and the numbers are, well, not great.
According to reporting by The Guardian, internal DfT analysis suggests the economic boost from expanding Heathrow could be up to 90% smaller than previously advertised. We're talking a measly 0.05% GDP uplift - and even that gets swallowed up by an overall negative trade-off that could cost the UK economy as much as £62.5 billion.
Yes, billion. With a B.
So what exactly is going on?
Ministers have been cheerfully promising to fast-track Heathrow expansion as a cornerstone of their economic growth agenda - essentially pitching a bigger airport as a golden ticket to prosperity. The rhetoric has been bold. The reality, if the DfT's own documents are to be believed, is considerably less cinematic.
The analysis reportedly shows that while a third runway would generate some economic activity, the overall costs and trade-offs would more than offset the benefits. That 0.05% GDP boost sounds small because it is small - roughly the kind of number that gets rounded off in most economic forecasts without anyone losing sleep.
The awkward bit
What makes this particularly spicy is the timing. The government has been loudly championing Heathrow expansion as a pro-growth policy even as its own department was apparently sitting on analysis that tells a rather different story. That's not a great look, no matter which side of the runway debate you sit on.
Opponents of the expansion - who have spent years arguing the project's costs outweigh its benefits, both economically and environmentally - will understandably be pointing at these numbers with considerable enthusiasm right about now.
What this means going forward
It would be premature to declare the third runway dead. Megaprojects of this scale have survived worse revelations, and governments have a long and distinguished history of pressing ahead with expensive infrastructure despite awkward internal memos. But this analysis does add significant fuel to the argument that the UK needs a much more honest public conversation about what Heathrow expansion is actually expected to deliver.
Spending political capital - and potentially tens of billions - on a project that your own department flags as a net economic negative is the sort of thing that tends to age poorly.
For now, the runway remains very much on the table. But the economic justification just got a lot harder to defend with a straight face.
