Families stranded, airports crippled and airlines in crisis: What it will look like if EU flights are grounded on day one of Brexit

Before dawn on 29 March 2019, the aviation day begins as normal with the first arrivals at Heathrow from the Far East. But as the passengers emerge blearily from their long-haul Airbuses and Boeings, the departure screens at Britain’s biggest airport show far fewer flights than usual.

The short-haul network has a very odd look: onward flights to Belfast, Belgrade, Istanbul, Moscow, Reykjavik and Gibraltar are scheduled, but the vast majority of European departures have been cancelled.

“Nothing is agreed until everything is agreed,” was the Brussels position throughout the Brexit negotiations. And with no firm agreement on how much the UK should pay the EU, the increasingly ill-tempered talks collapsed and Britain headed for the hardest of Brexits.

Lorries keep moving between Dover and Calais, but with “Operation Stack” in place because of the new customs checks and the thousands of motorists seeking to reach the continent by road.

But the default position of World Trade Organisation rules does not apply to aviation. No aircraft can fly between the UK and EU airports until a new agreement is reached on flights.

Transatlantic services on British Airways, Virgin Atlantic and their US rivals and partners are departing as normal, as the Trump administration has signed a “Bermuda III” agreement with the UK. It is similar to the EU-US open-skies treaty – with one important exception that only British and American carriers are allowed to fly between the two countries. Pressure from US airlines succeeded in culling Norwegian’s American network from Gatwick, Edinburgh and Belfast, which had operated through its British subsidiary. The Danish airline, Primera, has also stopped flights from Stansted and Birmingham.

Long-haul departures are barely affected, because the vast majority are governed by bilateral treaties with the UK. But they are much emptier than usual, because the feed to and from Europe has dried up. In the days leading up to 29 March, travel agents were frantically rebooking transfer passengers away from the UK, switching to connections in Amsterdam, Frankfurt and Paris.

International Airlines Group, the parent company of both British Airways and Iberia of Spain, has stepped up operations in Madrid to make up for the loss of so much traffic at Heathrow.

At other big UK airports, the closure is even more painful. Gatwick, Manchester, Stansted, Luton and Edinburgh are far more dependent on European flights than Heathrow.

While easyJet is able to continue to operate flights within the continent through its Austrian operation based in Vienna, at its Luton headquarters and main base, Gatwick, the picture is bleak. The only services are UK domestic flights and the odd service to Morocco and Israel.

At some smaller UK airports, such as Doncaster and Durham Tees Valley, there are no international services at all. Remainers have pointed out that these areas all voted strongly to leave the EU.

Airport retail, ground-handling and security staff have been sent home, with zero-hours workers laid off for the foreseeable future. Airports, traditionally seen as cash cows generating reliable revenues, are taking a big financial hit. But the airlines are really suffering.

Fares had soared in the final days of Britain’s membership of the EU, as business travellers and people with family in other European countries scrabbled for seats ahead of the expected shutdown. But with hundreds of aircraft and thousands of flight crew idle, airlines are losing tens of millions of pounds a day.

While the grounding of flights hurts the big European carriers, particularly Air France-KLM and Lufthansa, the real pain is being suffered by British Airways, easyJet and Ryanair. The Irish airline set up a UK subsidiary a year ago for the post-Brexit era, but today it is able to fly only to Kaliningrad in Russia, Skopje in Macedonia and Tirana in Albania.

Ryanair and its rivals are also responsible for paying for hotels and meals for tens of thousands of passengers stranded by the shutdown. There are fears that smaller, weaker airlines may fail as their revenues dry up and costs mount.

Brussels insisted that Ireland could not negotiate a separate agreement for UK flights, and so ferry firms are thriving as an estimated 20,000 passengers seek an alternative to flying.

Eurostar is attempting to schedule additional services from London to Paris and Brussels to cope with the extra demand, but the rail terminals are overcrowded and sclerotic because of the new customs checks.

With most schools not breaking up for Easter for a week or two, the big tour operators are hoping that some kind of deal can be salvaged. Portugal, Spain, Croatia and Greece lobbied intensively for open skies to continue, because they are so dependent on tourists from the UK. But other nations were keen for an example to be made of Britain.

Thomas Cook is preparing to invoke, if necessary, a little-noticed clause that it introduced to its terms in 2017: that in the event of “airspace closures", it has no liability for compensation, expenses or losses.

Now that foreign travel options are cut off, domestic tourism is expecting a short-term boost – though with business travel and city breaks from European visitors drying up, top London hotels are cutting rates below £100 a night to try to fill their beds.

The Chancellor is looking anxiously at tax receipts: besides the immediate loss of tens of millions in air passenger duty, there will be losses in VAT from inbound tourists and income tax from laid-off aviation workers.

While the Opposition has lambasted the Government for failing to secure an aviation deal, the Green Party has welcomed the grounding of thousands of flights. And the residents of west London are enjoying uncannily quiet skies, with the normal rate of arrivals at Heathrow more than halved.