—American Airlines Group Inc. pilots’ union called for the removal flight operations managers, citing years of poor performance including delays that forced the carrier to trim its schedule this summer.

“Throughout the summer of 2021, middle management chose to advance cancel hundreds of flights disrupting thousands of travel plans while at the same time damaging the American Airlines brand,” according to a resolution passed by the Allied Pilots Association’s board late Thursday.

Following summer weather issues, two-thirds of cancellations were “due to management’s failure to connect pilots with airplanes,” the resolution said. The union also said it would warn potential new pilots about how American’s scheduling policy could affect their quality of life.

The airline’s problems came to a head this summer when it scrapped 950 flights from its schedule in the first two weeks in July. That followed the cancellation of 775 over one weekend that the union says affected 60,000 travelers, as weather conditions exacerbated a shortage of pilots. The union, whose complaint cites poor performance since American’s 2013 merger with US Airways, is targeting upper middle managers responsible for operations and not top executives, a spokesman said Friday.

American declined to comment on the resolution. The carrier pointed to a memo sent to pilots ahead of the Labor Day weekend that noted improvements in their training and staffing, a 30% drop in cancellations tied to pilot availability and reduced use of reserves.

The Fort Worth, Texas-based airline and the union are in negotiations for a new contract.