Frontier CEO Barry Biffle said he has seen flights where 20 people were brought in wheelchairs at departure, with only three using them upon arrival.

The discount airline is calling for a “wheelchair registration” system and legislation cracking down on those “abusing” the accessibility tool.

Frontier Airlines passengers are abusing the company’s wheelchair service to skip the line and secure priority boarding on their flights, the budget airline claims. “There is massive, rampant abuse of special services.