JetBlue Airways Corp. has reached an initial agreement with its pilots union, marking the first such accord in the carrier’s history. The deal, announced Friday by the Air Line Pilots Association and confirmed by JetBlue, will be reviewed by union leaders, who will make adjustments to the final contract language and decide whether to send it to members for a vote. “This agreement in principle is the next step toward our final goal of having a fair and equitable contract with our company,” Patrick Walsh, head of the ALPA unit at JetBlue, said in a statement.