WASHINGTON (AP) - Federal regulators want to fine Southwest Airlines $3.9 million for violating standards on how to calculate the weight and load balance on flights. The Federal Aviation Administration says Southwest made improper calculations on more than 21,500 flights from May until early August of 2018. Weight is used to determine the maximum number of passengers on a plane and how much fuel it should carry. Cargo should be balanced to avoid have too much weight in the front or back, which can affect the way a plane handles. Southwest has 30 days to respond to the FAA.

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