JetBlue Airways Corp. and American Airlines face a U.S. Transportation Department probe after passengers were stranded on planes for as long as 7 1/2 hours when they were routed to Connecticut during a snowstorm. The flights were among 23 diverted to Hartford's Bradley airport on Oct. 29 by the storm and periodic equipment failures at two New York-area airports. Six were flown by JetBlue, which wouldn't say how long any of its jets were stuck on the tarmac.