Zodiac and an industry committee told the FAA that the directive was based on limited research, and cited accidents where reports did not mention serious neck injuries.

The FAA responded that it found sufficient data and identified an unsafe condition.

Airlines have five years to to remove the seats, with a total of 10,482 seats affected.

Delta said the directive affects all seats in the economy cabin and Comfort+ sections of its MD-90 and Boeing 717 aircraft. The airline said it will comply with the directive to replace the seats within the five years.

“The safety of our customers and aircraft is Delta’s top priority,” Delta said in a written statement.

Delta can replace the seats during scheduled maintenance checks and thus does not expect disruptions to flight schedules.