At 7:25 and 7:38 a.m. on a Tuesday in April, the day’s only paying passengers departing New Bedford Regional Airport lifted off into overcast skies on two nine-seat Cape Air twin-engine propeller planes. They were bound for Martha’s Vineyard and Nantucket, but mostly not for frolicking in Edgartown, or strolling Surfside Beach. The passengers, nine in all, were mostly headed to work.