United was plagued with a huge issue even before dragging a customer off a plane

The survey, which was conducted by the American Customer Satisfaction Index (ACSI), found that United was the lowest ranking legacy airline, with a score of 70 points out of a 100. However, the airline did improve from its 2016 score of 68 points. 

Considering the recent turmoil surrounding the company, this may not be that surprising. But the survey, which polled 180,000 people over 12 months, was actually completed in March before the incident involving a passenger being dragged off a United flight.

The incident happened on April 9 aboard a plane in Chicago heading to Louisville. The passenger, 69-year-old David Dao, was dragged off the plane by Chicago Aviation police officers after refusing to give up his seat on the plane.  A fellow passenger recorded the incident and the video quickly went viral.

The video sparked public outrage, not only against United, but against the airline industry in general for its practice of overbooking and treatment of passengers. 

According to the survey, though, consumers have been frustrated with the airline industry as a whole for some time. 

The airline industry ranked in the bottom third of all sectors, making it on par with hospital and private utilities. 

Consumers ranked low-cost airline JetBlue as the best US airline, with 82 points. American Airlines and Delta both tied for the best legacy airline, with 76 points. 

Check the full ranking below: 

1. JetBlue (82)
2. Southwest (80)3. Alaska (78)4. American (76)5. Delta (76)6. All others (74)7. Allegiant (71)8. United (70)9. Frontier (63)10. Spirit (61) 

NOW WATCH: UNITED PASSENGER ATTORNEY: Dao has a concussion, broken nose, and lost two front teeth

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