Flying today can be a hassle, what with long lines, small seats, harried flight attendants, rude passengers, and unavoidable delays. Passengers pay a premium for what many consider to be a stressful experience. The big airlines may fly to more destinations with bigger jets and more flights, but many travelers are turning to smaller budget airlines for savings, more comfort, and less aggravation. However, there are times when flying on a major carrier is unavoidable. Here are a few airlines to avoid when traveling around the world.

01United Airlines

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How the mighty have fallen. United Airlines, the nation's third-largest, has gone from one of the most popular airlines to one of the most heavily criticized. In 2017, a video of a passenger being dragged from an overbooked flight went viral. Not too long afterward, United sent a beloved pet to the wrong destination and, worse, was responsible for killing another passenger's dog. Perhaps to defuse customer complaints, United has started a test program that lets passengers know the reason for flights that are significantly behind schedule. But does knowing you will be spending more time in the uncomfortable airport seats or the overpacked lounge make it any better?

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02easyJet

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As one of Britain’s leading budget airlines, easyJet offers reasonable ticket prices to many international destinations, but its reputation for poor customer service has many potential passengers choosing alternative carriers for travel. Accusations of discrimination against travelers with physical disabilities have swirled around the company. There have been many complaints about the difficulty of receiving refunds for canceled or delayed flights. In one particular episode, a woman lost the seat she had reserved weeks in advance by another passenger whose seat was found to be defective.

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03Air Canada

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Air Canada was one of the first airlines to begin charging for luggage. Passengers quickly became irate because the company not only charged a premium for any bag but restricted carry-on size and weights. It is a good idea to travel light if you fly on this northern-based carrier. The airline is Canada's largest, with flights to some 160 destinations around the globe.

Many Canadians appreciate the ease with which they can reach far-ranging destinations from the home front. Unfortunately, Air Canada has become one of the most expensive airlines with which to book. One instance stands out for a frustrated group of passengers who booked an easy flight from Antigua to Toronto. The flight was delayed for four hours before the pilot aborted the takeoff when he slammed on the brakes. Later the plane had to make an emergency landing in San Juan, where the passengers had to share rooms for the overnight stay.

04Sunwing

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This charter airline offers reasonable prices but unreasonable customer service and accommodations, according to many passenger complaints. Chief among them: customers say Sunwing refuses extra services, particularly for those with physical disabilities. Recently, a Sunwing flight was stuck on the airport apron for several hours. Passengers claim they were "held hostage" and the incident only ended when a passenger called 911 for rescue. Travelers on a flight to Mexico endured an 18-hour flight interruption. During the agonizingly long wait, the airline failed to communicate regarding the reasons for the numerous delays.

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05Ryanair

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Europe's largest airline was responsible for a massive number of flight cancellations -- 2,200 in all -- in 2017. The Irish carrier allowed too many of its pilots to take a holiday due to a scheduling glitch. It was Europe's worst cancellation situation because of staff shortages. Ryanair gets unfavorable reviews by travelers for cost-cutting policies that result in baggage fees and ticket changes that cost the same as a regular ticket.

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06Delta Airlines

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Delta, the world's largest airline, probably has the world's longest list of complaints about customer service, flight delays, overbooking, and cancellations. The airline receives more online complaints than any other, many about rude or indifferent employees. One passenger said his confirmed seat to Europe changed suddenly to stand-by when he arrived at the airport. Another passenger who missed a flight was denied a seat on another flight even though there were empty seats available.

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07JetBlue

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JetBlue remains one of the nation's most popular budget carriers. However, the airline is criticized constantly for poor customer relations and problems with ever-changing flight statuses. The biggest issue with the carrier, according to numerous passengers, is that if you stranded in the airport by a canceled flight -- a frequent occurrence -- JetBlue will not take care of your accommodations or pay any part of your lodging bill.

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