Safe Landing have submitted our response to the UK Government’s consultation on the draft Heathrow Expansion National Policy Statement (HENPS).
Read our full response here: HENPS Consultation – Safe Landing Response
Our conclusion is straightforward: the draft should not be approved in its current form.
We recognise the importance of aviation and international connectivity. But the case for expanding Heathrow cannot be separated from the UK’s climate targets, and it could be both environmentally and economically counterproductive to spend tens of billions building a third runway that cannot be used as planned once it opens.
We also recognise the current significance of Heathrow to the UK economy, but believe that the best way to harness UK aviation for future economic growth involves an alternative, faster, cheaper and forward-facing approach.
The key question
There is clearly demand for air travel. But demand is not the same thing as a case for more airport capacity.
Before committing to expansion, any airport must agree that additional flights will only be able to operate within the UK’s legally-binding environmental targets.
At present, we don’t believe the draft HENPS provides this clarity.
Put a carbon budget in place first
Our most important recommendation is simple: set the carbon budget before building the infrastructure.
The UK Government should establish a quantified UK aviation carbon budget, with a corresponding airport-specific carbon budget for Heathrow (and other UK airports). Expansion should then be conditional on staying within that budget. Actual emissions should be monitored via jet fuel sales, with consequences if the limits are exceeded.
That is safer than approving new capacity today on the assumption that future aircraft, fuels and technologies will deliver the required emissions reductions.
Make the four tests real tests
We also want the UK Government’s four tests for airport expansion to become genuine, enforceable conditions.
That means:
- Air quality: expansion must not cause or contribute to breaches of legal limits.
- Noise: health impacts, night-time exposure and individual noise events must be properly accounted for.
- Climate: Heathrow’s cumulative emissions must stay within a defined carbon budget.
- Economic growth: the Government must demonstrate genuinely additional national economic benefits, not simply economic activity associated with the project.
A different future for aviation
This is not about abandoning aviation.
The UK has an opportunity to lead in greener, cleaner, quieter and genuinely sustainable flight — including zero-carbon and hybrid-electric aircraft, contrail avoidance, improved airspace efficiency and investment in UK aerospace research and manufacturing.
We believe zero-carbon and hybrid-electric aircraft offer a particularly promising economic opportunity for the UK to pioneer a new industry and clean technology, create thousands of jobs and provide spill-over benefits to other areas of our economy. However, these aircraft are unsuitable for large long-haul international airports such as Heathrow, and we believe an alternative industrial strategy should be pursued that makes best use of existing under-utilised regional and private jet airports instead to deliver this.
We should be building that future, rather than locking in additional conventional aviation capacity before the environmental case has been demonstrated.
Our message to Government
Set the limits. Make expansion conditional on meeting them. Monitor what actually happens.
If Heathrow can expand while remaining within the UK’s climate and environmental limits, it should be able to demonstrate that case – but it must agree to a carbon budget upfront.
If it cannot, then expansion should not take place.
That is the basis for a genuinely sustainable aviation policy.
Note: this response and proposals were presented and discussed at a community assembly on 20th Aug 2026. Watch the presentation from this session here: https://safe-landing.org/heathrow-airport-assembly-aug2026/