FORT WORTH (CBS 11 NEWS) – Bad news for American Airlines pilots in September often turned into instant bad news for passengers, based on a review of performance data released by Marks Systems’ masFlight.

Some of the worst days for on-time performance and cancellations, coincided with key days in the current labor battle between the air carrier and the union representing more than 8,000 pilots.

masFlight shows cancellations and arrivals more than 14 minutes late first dropped sharply September 4 and 5. September 4 was the day a federal bankruptcy court judge officially abrogated the contract between American and the Allied Pilots Association.

Performance slowly improved until September 13. That was the day the airline began to implement dozens of new work rules for pilots, affecting pay and benefits. The data shows another drop four days later, when American first acknowledged having difficulty with operations.

Performance was at its best in nearly two weeks September 26, the day pilots agreed to go back to the bargaining table with the airline. It dropped sharply again on the 27th coinciding with a letter from the company threatening legal action against the APA in order to stop the slowdown.

American cited an increase in pilot sick calls that month along with last minute maintenance calls as the reason for the operations problems. The APA consistently denied any organized slow down while saying its members were angry about work conditions with the airline. The APA had no official comment on the data today.

American’s performance has gradually improved in October. Data from American Airlines showed its performance was above 80-percent this past weekend. The APA said Monday it was making progress with the company.

CBS11 meteorologists checked weather patterns locally and nationally during some of the worst performing days. Only on September 4, when there were storms in the upper Midwest and in the South, did major weather events coincide with an increase in American cancellations and delays.

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