The union also said that American should have rehired more furloughed pilots.
Other airline unions have expressed their displeasure with management by calling in sick or slowing operations, and some have gotten in trouble.
Last September, a federal judge ordered the union for US Airways pilots to stop disrupting the airline by making sure flights were late. In 2008, a judge determined that United Airlines pilots carried out illegal sickouts and slowdowns and ordered them to stop.
American's pilot union was fined $45 million after a 1999 sickout over bringing in pilots from a low-cost airline that AMR bought. AMR and the union reached a settlement that reduced the union's loss.
In each instance, the airline went to court to force pilots to speed things up. Crandall said American might be forced to do the same thing this time.
"It is perfectly obvious that this is a job action by the pilots," Crandall said. "I think it's childish, it's self-defeating and it's harmful to the company and to other employees."
American is particularly vulnerable to long-term damage if passengers choose other carriers because it is already in bankruptcy and weak compared with bigger rivals United and Delta, he said.
As the week has unfolded, and American posted slightly better on-time arrivals, travel experts advised passengers to wait before they decide to avoid American.
"When people ask, 'Should I book away from American?' I think about whether I'd want my mom getting stranded at (the Dallas-Fort airport) because American canceled her flight home," said Tim Winship, who runs travel website FrequentFlier.com. "I'd tell her to go ahead and book the trip."
Winship's advice is colored by his reluctance to pile on a beleaguered airline.
"They need the business more than ever," he said. "I'd hate to be one of the nails in their coffin."
George Hobica, founder of airfarewatchdog.com and a frequent flier, predicted that American will soon fix the delays and cancelations. He said he's seen company employees trying extra hard to be nice and to help passengers who are bumped or otherwise inconvenienced.
American's predicament comes during one of the slowest travel periods of the year. That will help the airline find new flights for stranded passengers, Hobica said.
"I'm flying on American on Friday," Hobica said, "and I'm not going to change my plans."
Follow David Koenig at http://www.twitter.com/airlinewriter