The airport on Friday (11 March) said that even at 85% of pre-pandemic passenger numbers, it would likely feel "even busier" owing to additional pre-departure checks.

It also raised concerns over Border Force’s ability to scale up its operation at the airport, and the potential impact of a new, more restrictive five-year regulatory and financial framework which it said risked the return of "Heathrow hassle" with long queues and delays.

The CAA is due to determine the new settlement later this year.

Speaking as Heathrow on Friday revealed February passenger numbers were still nearly 50% down on pre-pandemic levels, and were lagging 15% behind the airport’s forecast, chief John Holland-Kaye said the recovery of the UK’s aviation sector still faced a number of very real threats.

“Aviation’s recovery remains overshadowed by war and Covid uncertainty," he said. "We need to ensure we are geared up to meet peak potential demand this summer and are relying on the CAA to make a fair financial settlement that incentivises investment to maintain passenger service and encourages airlines and Heathrow to work together to grow passenger numbers."

Just 2.8 million passengers travelled though Heathrow in February, compared with 5.48 million in February 2019.

Heathrow said outbound leisure demand was "recovering strongly" as destinations roll back their Covid travel restrictions, while stressing demand for inbound leisure and business travel remained suppressed owing to the testing and quarantine requirements in place in "nearly two-thirds" of the markets the airport serves.

Moreover, the airport said there was a litany of bigger issues that could yet rear their head. "We also face headwinds from higher fuel prices, longer flight times to destinations impacted by airspace closures, concerns from US travellers over war in Europe and the likelihood of new “variants of concern”, which together create huge uncertainty over the passenger forecasts this year," said Heathrow.

‘Peak demand’

On the summer peak, Heathrow said there was still a huge amount of work to do to get ready for the likely levels of demand. "Based on the strength of outbound leisure bookings being reported by airlines, peak days in the summer holidays could be very busy, at up to 85% of pre-pandemic levels. This is likely to feel even busier in check in because of the additional pre-departure checks.

"This is higher than current airline, handler and airport capacity, so we are putting passengers first by gearing up across the airport for peak demand, working with airlines to reduce check in times and recruiting 12,000 new colleagues, as well as reopening Terminal 4 before July. We are particularly concerned over Border Force’s ability to scale up to meet demand."

Heathrow also urged the CAA not to curb Heathrow’s power to invest in its operations, including plans for a new baggage system in Terminal 2 and new security scanners that won’t require passengers to remove liquids and electronics from their bags.

The airport said it intended to do this while limiting an increase in fares to a maximum of 2%. "We are... relying on the CAA not to slash investment in capital projects or operating costs, which would risk the return of ’Heathrow hassle’, with long queues and delays," the airport added.