Heathrow plans for third runway face ‘misleading or misleading’ warning over cost and timeline

Plans to build a third runway at Heathrow Airport have come under fresh scrutiny after a report accused the airport of “misrepresenting” its claims that the project could be delivered within a decade without relying on taxpayers’ money.

The report, commissioned by infrastructure consultant Paul Mansell, warns that government-backed expansion could put both the airport and airlines at serious financial risk if the project encounters delays and cost overruns similar to those that plagued the HS2 rail system.

Heathrow has estimated that a third runway, along with major improvements to terminals and infrastructure, could be delivered for around £49 billion, with the first flights operating in 2035. The airport has repeatedly stressed that the project will be privately funded, meaning it will not require direct taxpayer funding.

However, critics argue that the true cost of the expansion will ultimately be borne by airlines and passengers through higher airport costs.

Airlines have already voiced strong opposition to the Heathrow proposals, warning that expansion could significantly increase the cost of air travel at Britain’s busiest airport.

Among the most critical are International Airlines Group, which owns British Airways, and Virgin Atlantic and other companies operating at Heathrow.

Airlines fear that the project will be heavily funded by higher landing fees, which are paid by airlines for using airport infrastructure and often passed on to passengers through ticket prices.

Industry estimates suggest that costs per passenger could double if Heathrow goes ahead with its proposed investment plan.

The airport has also revealed plans to increase spending to £59 billion in its next regulatory period, known as H8. That figure includes around £10 billion needed just to maintain and operate the airport over the next five years.

According to Mansell’s report, the scale of the expenditure represents a dramatic increase compared to Heathrow’s current investment levels.

“The scale of the proposed capital expenditure is staggering,” the report said, warning that consumers would end up being financially burdened.

The report also questions whether Heathrow’s proposed timeline is realistic.

Even if the airport succeeds in getting planning permission in 2029, the schedule will require the new runway to be operational six years later.

Mansell argued that such projections risk falling into what experts describe as “strategic misrepresentation”, a phenomenon where infrastructure developers underestimate costs or time periods to increase the chances of political approval.

According to the report, experts contacted during the review described the predictions bluntly as “fake or hoax.”

Heathrow said the timeline depends on external factors, including planning changes and regulatory approvals, and insists the plan remains feasible under the right circumstances.

The report also raises broader concerns about governance and transparency around the expansion project.

It warns of a “breakdown of trust” between Heathrow and its airline partners, citing poor relations over previous infrastructure investments at the airport.

Airlines have pointed to examples of major cost overruns and delays in recent Heathrow projects.

One example cited is the replacement of the baggage system at Terminal 2, which saw costs rise to almost £1 billion, from an original budget of £645 million. Some major infrastructure improvements including tunnel repairs were reported to have been delivered four times in their original budget and more than a decade has passed.

The report says such examples raise questions about Heathrow’s ability to deliver such a massive project on time and within budget.

“If a similar failure were to occur at Heathrow,” the report said, “it would seriously damage UK aviation, weaken confidence in the UK’s infrastructure and construction sectors, and sink Heathrow and its aircraft under the waterline.”

The report was commissioned by Heathrow Reimagined, a coalition of airlines and aviation stakeholders campaigning for changes to the airport’s regulatory framework.

It comes ahead of a key decision by the Civil Aviation Authority, which is currently examining Heathrow’s proposed investment plans and ways to allow the airport to pass costs on to airlines.

Among the report’s recommendations are changes to Heathrow’s management system and the introduction of stronger oversight mechanisms to ensure airlines and passengers are involved in major investment decisions.

It also suggests that an independent body such as the Civil Aviation Authority should play a greater role in considering Heathrow’s long-term spending plans.

Heathrow has dismissed the criticism, saying its track record shows it can successfully deliver large infrastructure projects.

A spokesperson for the airport said the expansion plans were made based on the lessons learned from previous major projects.

“We have seen the lessons of HS2 and are confident in our plans, which build on our success with major private projects such as Terminals 5 and 2, which have been delivered on time and on budget,” the spokesperson said.

Heathrow also urged airlines to participate constructively in discussions about expansion instead of using what he described as “biased reports”.

Despite the criticism, the UK government remains broadly supportive of expanding Heathrow’s capacity as part of a wider strategy to improve international connectivity and economic growth.

A spokesman for the Department of Transport said the expansion of Heathrow would strengthen Britain’s trade ties and attract investors.

“Expanding Heathrow will attract international investment and strengthen Britain’s connectivity, with the airport supporting hundreds of thousands of jobs across the country,” a spokesman said.

The transportation secretary has also launched a review of the National Airport Policy Statement, a key policy framework that supports the approval process for major airport expansions.

The debate over Heathrow’s third runway has been raging for decades, balancing the economic arguments for increasing flight capacity against environmental concerns and local opposition.

Supporters say expansion is essential if the UK is to remain competitive as a global aviation hub.

Critics warn that the project risks becoming another expensive infrastructure project if costs rise and timelines slip.

With regulatory decisions looming and tensions growing between Heathrow and its airline customers, the future of Britain’s most important airport expansion project is far from settled.