Hold Onto Your Hats (and Bags). Travelers to Europe Face Chaos.

The start of the summer travel season in Europe has been marred by chaos at airports and popular tourist destinations as airlines, government agencies and industry operators struggle to meet travel demand, which, in some spots, has already surpassed 2019 levels.

The mayhem is likely to get worse, travel experts warn, as more people decide to travel following the recent decision by the Biden administration to drop its coronavirus testing requirement for international air travel.

Hundreds of flights have been canceled and delayed daily at major European airport hubs over the past two weeks. At London’s Heathrow and Amsterdam’s Schiphol airports, passengers waited up to six hours in security lines, and those waiting to check-in spilled out of the terminals into parking lots.

“It was just huge crowds of confused and frustrated people everywhere and no information,” said Eliza Glass, 28, who arrived at Heathrow earlier this month to find her flight to Toronto had been canceled. “After one hour of walking around in circles, I just sat on my suitcase and cried.”

In the United States, airports and airlines face labor shortages, adverse weather conditions and a rise in worker coronavirus cases, but wait times, delays and cancellations have not reached the same level.Airlines canceled more than 2,800 flights over the Memorial Day weekend and 20,644 flights were delayed, according to FlightAware, an aviation data site, and several air carriers, including Delta Air Lines, JetBlue Airways and Spirit Airlines, are reducing their summer schedules to help prevent further disruptions.

For those planning to travel to Europe this summer, here’s a look at how they could be affected by disruptions, and some tips on how to prepare.

What is causing the chaos at European airports?

The travel industry calls it “the perfect storm” with multiple contributing factors. The lifting of coronavirus travel restrictions across Europe since April caused a sudden surge in demand and travel companies are struggling to staff their operations.

Airports and airlines laid off tens of thousands of workers during the height of the pandemic and many of them are reluctant to come back to their old jobs, many of which offered low pay and long hours. Recruiting and training new staff, particularly pilots and airport security staff, can take time and many positions are unlikely to be filled in time for peak summer travel.

“It is a disgrace what is happening — a terrible situation for travelers, airlines and travel organizations and a result of bad planning,” said Frank Oostdam, director of the Dutch Association of Travel Agents and Tour Operators, a representative body for the travel industry in the Netherlands.

Adding to the upheaval, aviation workers in Europe have held strikes in recent weeks, demanding better working conditions and higher salaries to help ease the burden of soaring inflation. Paris Charles de Gaulle airport canceled more than 100 flights on Thursday after its union announced a walkout demanding a 300-euro monthly pay raise for all airport staff, around $320. More than 360 flights were canceled in and out of Italian airports last week after air traffic controllers and cabin crew staged a 24-hour strike. Scandinavian Airlines pilots have also threatened to walk out beginning in late June over salary disputes.

Willie Walsh, director general for the International Air Transport Association, an airline trade group, said that coronavirus policy changes by governments created a lot of uncertainty and gave the travel industry little time to prepare for the restart of travel after a two-year shutdown.

“It is no wonder that we are seeing operational delays in some locations,” he said.

I’m already booked. What could I be facing?

Be prepared for long lines, flight cancellations and delays, even after you’ve arrived at the airport for check-in, as some airlines are changing flight schedules at the last minute to manage staffing issues. Download your carrier’s app to get the most up-to-the-minute changes and for easier rebooking from your phone.

At many European airports, travel experts are advising passengers to arrive three to four hours before their scheduled flights to get through long lines. For those traveling from the United States to Europe, try to take the most direct route to your destination and make sure there are several flights scheduled to your final destination in case you are transiting through a busy airport and miss your connection.

The staff shortages at airports have also caused baggage delivery delays with some passengers waiting up to a week to reclaim their luggage. Some travel operators are advising travelers not to check baggage, but if traveling light is not an option, then be sure to pack a carry-on with essential items for the first few days of your trip.

Earlier this month, Esra Topaz, 22, a fine arts student, flew from Paris to London on a British Airways flight that was delayed by more than five hours; her checked luggage never arrived. After she spent three days chasing the airline, her bag was finally delivered to her house, reeking of cheese and other perishable goods she had brought back from her trip.

“I was on hold for hours trying to track down my bag, but it was impossible to get any clear information,” she said. “So many flights had been changed they didn’t know which one my bag was on.”

Peter Vlitas, the executive vice president of partner relations for Internova Travel Group, which represents more than 70,000 travel advisers worldwide, says it’s important to have a contingency plan in case anything goes wrong with planned flight itineraries. “If you land in a main airport in Europe and your flight gets canceled and you can’t reschedule right away because of capacity issues or strikes, then there’s a good possibility you could take a train or a ferry to where you want to go. Whether it’s the French countryside or the Greek islands, there are other ways to get there,” he said.

Could it get worse?

Unfortunately, it could. Travel industry representatives and unions anticipate that the disruptions will get worse before they get better, particularly during the peak summer months of July and August. The Biden administration’s decision to drop the requirement for a negative coronavirus test before flying to the United States may only add to the surge in demand.

Mr. Vlitas of the Internova Travel group said he had hoped the United States would not lift its testing requirement until July because he does not think travel operators will be able to handle the demand it will bring this month.

“It will only compound the issues we are facing now and hurt recovery,” he said.

Many Americans who have put off international travel plans throughout the pandemic are looking for spontaneous travel opportunities this summer, according to a recent study by Skyscanner, a booking site, which analyzed Google search volume and trends across different travel-related keywords. Searches for “cheap flights anywhere” are up 600 percent and searches for “how to book a same-day flight” are up 200 percent from June 2021, according to the study.

Adrian Lee, 43, a structural engineer from Houston, said he has price alerts set up on several online travel sites so he can catch a last-minute deal for a vacation to Europe with his wife.

“At this point, we’ll go anywhere, we are dying to get out,” he wrote in an email. “We’re just waiting for the best deal to come up because everything is crazy expensive right now.”

Can anyone help?

Both American and European carriers are required to offer you a refund if they cancel or reschedule your flight significantly and you decide not to travel. But they are not required to compensate you for accommodations, car rentals or other prebooked services on your trip.

This may be the summer to consider travel insurance to cover costs tied to flight disruptions like accommodations and lost baggage, but be sure to read the fine print as policies vary and may only provide limited coverage, according to the U.S. Travel Insurance Association. When booking a trip, it is also helpful to opt for the most flexible cancellation policies at hotels and car rental companies to avoid paying extra charges if anything goes wrong.

Using a travel adviser can be useful, especially if your trip has multiple layers and destinations as the flight disruptions can have a domino effect, upending lodging reservations and any other time-sensitive bookings. The adviser can help navigate obstacles and make changes to your itinerary while you are in transit — though they, too, may face hiccups.

“It’s a real challenge because response times are really slow from hotels, concierge services and rental cars, so I’m having to reach out to general managers and other representatives to make changes for my clients,” said Tiffany Bowne, the founder of the luxury travel agency Lounge Couture. “We are dealing with these scenarios in June, which is a little terrifying in terms of what July and August will look like.”

But even travel advisers are telling their clients to “practice patience” and be open-minded and flexible with any last-minute changes that may occur because of disruptions.

“If you can roll with it and be flexible to change, then you’re going to end up having a better time,” Ms. Bowne said.

These crowds can’t be good for keeping the virus in check, can they?

Jessica Hubler, a 53-year-old composer, tested positive on Sunday after returning home to Philadelphia after a two-week vacation in Portugal. She is convinced she caught the virus at the Lisbon airport, which like most European transport hubs has dropped its mask mandate.

“I waited to check in for an hour and then it was two hours in the customs line of hundreds of people with no social distancing or masks and then another hour at the gate,” she said.

“Everyone is so excited to go on vacation again, they’ve forgotten about Covid, and governments don’t care because they need to make up for lost tourism dollars,” she said. “If they don’t sort out this mess then we’re going to find ourselves in another public health emergency.”

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