As the busy summer travel season approaches, 25,000 union pilots at two of the nation’s largest commercial airlines — American and Southwest — are taxiing on the runway of a potential strike. Last week, the Allied Pilots Association (APA), which represents 15,000 pilots at American Airlines, announced that its members had voted overwhelmingly to authorize a work stoppage. Signaling their unity, thousands of uniformed APA members held informational pickets on May Day at ten of the nation’s major airports, including Chicago’s O’Hare and Boston’s Logan. “With more than 99% of participating pilots voting in favor of authorizing a strike, our pilots’ resolve is unmistakable,” said Capt. Ed Sicher, APA president.